Commit Graph

1277 Commits

Author SHA1 Message Date
Yaowei Bai
378b417d65 KVM: powerpc: kvmppc_visible_gpa can be boolean
In another patch kvm_is_visible_gfn is maken return bool due to this
function only returns zero or one as its return value, let's also make
kvmppc_visible_gpa return bool to keep consistent.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:24 +01:00
Linus Torvalds
3370b69eb0 Four changes:
- x86: work around two nasty cases where a benign exception occurs while
 another is being delivered.  The endless stream of exceptions causes an
 infinite loop in the processor, which not even NMIs or SMIs can interrupt;
 in the virt case, there is no possibility to exit to the host either.
 
 - x86: support for Skylake per-guest TSC rate.  Long supported by AMD,
 the patches mostly move things from there to common arch/x86/kvm/ code.
 
 - generic: remove local_irq_save/restore from the guest entry and exit
 paths when context tracking is enabled.  The patches are a few months
 old, but we discussed them again at kernel summit.  Andy will pick up
 from here and, in 4.5, try to remove it from the user entry/exit paths.
 
 - PPC: Two bug fixes, see merge commit 370289756b for details.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull second batch of kvm updates from Paolo Bonzini:
 "Four changes:

   - x86: work around two nasty cases where a benign exception occurs
     while another is being delivered.  The endless stream of exceptions
     causes an infinite loop in the processor, which not even NMIs or
     SMIs can interrupt; in the virt case, there is no possibility to
     exit to the host either.

   - x86: support for Skylake per-guest TSC rate.  Long supported by
     AMD, the patches mostly move things from there to common
     arch/x86/kvm/ code.

   - generic: remove local_irq_save/restore from the guest entry and
     exit paths when context tracking is enabled.  The patches are a few
     months old, but we discussed them again at kernel summit.  Andy
     will pick up from here and, in 4.5, try to remove it from the user
     entry/exit paths.

   - PPC: Two bug fixes, see merge commit 370289756b for details"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (21 commits)
  KVM: x86: rename update_db_bp_intercept to update_bp_intercept
  KVM: svm: unconditionally intercept #DB
  KVM: x86: work around infinite loop in microcode when #AC is delivered
  context_tracking: avoid irq_save/irq_restore on guest entry and exit
  context_tracking: remove duplicate enabled check
  KVM: VMX: Dump TSC multiplier in dump_vmcs()
  KVM: VMX: Use a scaled host TSC for guest readings of MSR_IA32_TSC
  KVM: VMX: Setup TSC scaling ratio when a vcpu is loaded
  KVM: VMX: Enable and initialize VMX TSC scaling
  KVM: x86: Use the correct vcpu's TSC rate to compute time scale
  KVM: x86: Move TSC scaling logic out of call-back read_l1_tsc()
  KVM: x86: Move TSC scaling logic out of call-back adjust_tsc_offset()
  KVM: x86: Replace call-back compute_tsc_offset() with a common function
  KVM: x86: Replace call-back set_tsc_khz() with a common function
  KVM: x86: Add a common TSC scaling function
  KVM: x86: Add a common TSC scaling ratio field in kvm_vcpu_arch
  KVM: x86: Collect information for setting TSC scaling ratio
  KVM: x86: declare a few variables as __read_mostly
  KVM: x86: merge handle_mmio_page_fault and handle_mmio_page_fault_common
  KVM: PPC: Book3S HV: Don't dynamically split core when already split
  ...
2015-11-12 14:34:06 -08:00
Linus Torvalds
2f4bf528ec powerpc updates for 4.4
- Kconfig: remove BE-only platforms from LE kernel build from Boqun Feng
  - Refresh ps3_defconfig from Geoff Levand
  - Emit GNU & SysV hashes for the vdso from Michael Ellerman
  - Define an enum for the bolted SLB indexes from Anshuman Khandual
  - Use a local to avoid multiple calls to get_slb_shadow() from Michael Ellerman
  - Add gettimeofday() benchmark from Michael Neuling
  - Avoid link stack corruption in __get_datapage() from Michael Neuling
  - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar K.V
  - Add ppc64le_defconfig from Michael Ellerman
  - pseries: extract of_helpers module from Andy Shevchenko
  - Correct string length in pseries_of_derive_parent() from Nathan Fontenot
  - Free the MSI bitmap if it was slab allocated from Denis Kirjanov
  - Shorten irq_chip name for the SIU from Christophe Leroy
  - Wait 1s for secondaries to enter OPAL during kexec from Samuel Mendoza-Jonas
  - Fix _ALIGN_* errors due to type difference. from Aneesh Kumar K.V
  - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from Colin Ian King
  - Disable hugepd for 64K page size. from Aneesh Kumar K.V
  - Differentiate between hugetlb and THP during page walk from Aneesh Kumar K.V
  - Make PCI non-optional for pseries from Michael Ellerman
  - Individual System V IPC system calls from Sam bobroff
  - Add selftest of unmuxed IPC calls from Michael Ellerman
  - discard .exit.data at runtime from Stephen Rothwell
  - Delete old orphaned PrPMC 280/2800 DTS and boot file. from Paul Gortmaker
  - Use of_get_next_parent to simplify code from Christophe Jaillet
  - Paginate some xmon output from Sam bobroff
  - Add some more elements to the xmon PACA dump from Michael Ellerman
  - Allow the tm-syscall selftest to build with old headers from Michael Ellerman
  - Run EBB selftests only on POWER8 from Denis Kirjanov
  - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael Ellerman
  - Avoid reference to potentially freed memory in prom.c from Christophe Jaillet
  - Quieten boot wrapper output with run_cmd from Geoff Levand
  - EEH fixes and cleanups from Gavin Shan
  - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
  - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael Ellerman
  - Fix section mismatch warning in msi_bitmap_alloc() from Denis Kirjanov
  - Fix ps3-lpm white space from Rudhresh Kumar J
  - Fix ps3-vuart null dereference from Colin King
  - nvram: Add missing kfree in error path from Christophe Jaillet
  - nvram: Fix function name in some errors messages. from Christophe Jaillet
  - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro Koskinen
  - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
  - cxl: Free virtual PHB when removing from Andrew Donnellan
  - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from Michael Ellerman
  - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building with O= from Michael Ellerman
 
  - Freescale updates from Scott: Highlights include 64-bit book3e kexec/kdump
    support, a rework of the qoriq clock driver, device tree changes including
    qoriq fman nodes, support for a new 85xx board, and some fixes.
 
  - MPC5xxx updates from Anatolij: Highlights include a driver for MPC512x
    LocalPlus Bus FIFO with its device tree binding documentation, mpc512x
    device tree updates and some minor fixes.
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Merge tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Kconfig: remove BE-only platforms from LE kernel build from Boqun
   Feng
 - Refresh ps3_defconfig from Geoff Levand
 - Emit GNU & SysV hashes for the vdso from Michael Ellerman
 - Define an enum for the bolted SLB indexes from Anshuman Khandual
 - Use a local to avoid multiple calls to get_slb_shadow() from Michael
   Ellerman
 - Add gettimeofday() benchmark from Michael Neuling
 - Avoid link stack corruption in __get_datapage() from Michael Neuling
 - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar
   K.V
 - Add ppc64le_defconfig from Michael Ellerman
 - pseries: extract of_helpers module from Andy Shevchenko
 - Correct string length in pseries_of_derive_parent() from Nathan
   Fontenot
 - Free the MSI bitmap if it was slab allocated from Denis Kirjanov
 - Shorten irq_chip name for the SIU from Christophe Leroy
 - Wait 1s for secondaries to enter OPAL during kexec from Samuel
   Mendoza-Jonas
 - Fix _ALIGN_* errors due to type difference, from Aneesh Kumar K.V
 - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from
   Colin Ian King
 - Disable hugepd for 64K page size, from Aneesh Kumar K.V
 - Differentiate between hugetlb and THP during page walk from Aneesh
   Kumar K.V
 - Make PCI non-optional for pseries from Michael Ellerman
 - Individual System V IPC system calls from Sam bobroff
 - Add selftest of unmuxed IPC calls from Michael Ellerman
 - discard .exit.data at runtime from Stephen Rothwell
 - Delete old orphaned PrPMC 280/2800 DTS and boot file, from Paul
   Gortmaker
 - Use of_get_next_parent to simplify code from Christophe Jaillet
 - Paginate some xmon output from Sam bobroff
 - Add some more elements to the xmon PACA dump from Michael Ellerman
 - Allow the tm-syscall selftest to build with old headers from Michael
   Ellerman
 - Run EBB selftests only on POWER8 from Denis Kirjanov
 - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael
   Ellerman
 - Avoid reference to potentially freed memory in prom.c from Christophe
   Jaillet
 - Quieten boot wrapper output with run_cmd from Geoff Levand
 - EEH fixes and cleanups from Gavin Shan
 - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
 - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael
   Ellerman
 - Fix section mismatch warning in msi_bitmap_alloc() from Denis
   Kirjanov
 - Fix ps3-lpm white space from Rudhresh Kumar J
 - Fix ps3-vuart null dereference from Colin King
 - nvram: Add missing kfree in error path from Christophe Jaillet
 - nvram: Fix function name in some errors messages, from Christophe
   Jaillet
 - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro
   Koskinen
 - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
 - cxl: Free virtual PHB when removing from Andrew Donnellan
 - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from
   Michael Ellerman
 - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building
   with O= from Michael Ellerman
 - Freescale updates from Scott: Highlights include 64-bit book3e
   kexec/kdump support, a rework of the qoriq clock driver, device tree
   changes including qoriq fman nodes, support for a new 85xx board, and
   some fixes.
 - MPC5xxx updates from Anatolij: Highlights include a driver for
   MPC512x LocalPlus Bus FIFO with its device tree binding
   documentation, mpc512x device tree updates and some minor fixes.

* tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (106 commits)
  powerpc/msi: Fix section mismatch warning in msi_bitmap_alloc()
  powerpc/prom: Use of_get_next_parent() in of_get_ibm_chip_id()
  powerpc/pseries: Correct string length in pseries_of_derive_parent()
  powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry
  powerpc/mpc85xx: Add FSL QorIQ DPAA FMan support to the SoC device tree(s)
  powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan
  powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes
  powerpc: handle error case in cpm_muram_alloc()
  powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake
  powerpc/book3e-64: Enable kexec
  powerpc/book3e-64/kexec: Set "r4 = 0" when entering spinloop
  powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32
  powerpc/book3e-64/kexec: Enable SMP release
  powerpc/book3e-64/kexec: create an identity TLB mapping
  powerpc/book3e-64: Don't limit paca to 256 MiB
  powerpc/book3e/kdump: Enable crash_kexec_wait_realmode
  powerpc/book3e: support CONFIG_RELOCATABLE
  powerpc/booke64: Fix args to copy_and_flush
  powerpc/book3e-64: rename interrupt_end_book3e with __end_interrupts
  powerpc/e6500: kexec: Handle hardware threads
  ...
2015-11-05 23:38:43 -08:00
Paul Mackerras
f74f2e2e26 KVM: PPC: Book3S HV: Don't dynamically split core when already split
In static micro-threading modes, the dynamic micro-threading code
is supposed to be disabled, because subcores can't make independent
decisions about what micro-threading mode to put the core in - there is
only one micro-threading mode for the whole core.  The code that
implements dynamic micro-threading checks for this, except that the
check was missed in one case.  This means that it is possible for a
subcore in static 2-way micro-threading mode to try to put the core
into 4-way micro-threading mode, which usually leads to stuck CPUs,
spinlock lockups, and other stalls in the host.

The problem was in the can_split_piggybacked_subcores() function, which
should always return false if the system is in a static micro-threading
mode.  This fixes the problem by making can_split_piggybacked_subcores()
use subcore_config_ok() for its checks, as subcore_config_ok() includes
the necessary check for the static micro-threading modes.

Credit to Gautham Shenoy for working out that the reason for the hangs
and stalls we were seeing was that we were trying to do dynamic 4-way
micro-threading while we were in static 2-way mode.

Fixes: b4deba5c41
Cc: vger@stable.kernel.org # v4.3
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-11-06 16:02:59 +11:00
Paul Mackerras
cf29b21595 KVM: PPC: Book3S HV: Synthesize segment fault if SLB lookup fails
When handling a hypervisor data or instruction storage interrupt (HDSI
or HISI), we look up the SLB entry for the address being accessed in
order to translate the effective address to a virtual address which can
be looked up in the guest HPT.  This lookup can occasionally fail due
to the guest replacing an SLB entry without invalidating the evicted
SLB entry.  In this situation an ERAT (effective to real address
translation cache) entry can persist and be used by the hardware even
though there is no longer a corresponding SLB entry.

Previously we would just deliver a data or instruction storage interrupt
(DSI or ISI) to the guest in this case.  However, this is not correct
and has been observed to cause guests to crash, typically with a
data storage protection interrupt on a store to the vmemmap area.

Instead, what we do now is to synthesize a data or instruction segment
interrupt.  That should cause the guest to reload an appropriate entry
into the SLB and retry the faulting instruction.  If it still faults,
we should find an appropriate SLB entry next time and be able to handle
the fault.

Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-11-06 15:40:42 +11:00
Linus Torvalds
933425fb00 s390: A bunch of fixes and optimizations for interrupt and time
handling.
 
 PPC: Mostly bug fixes.
 
 ARM: No big features, but many small fixes and prerequisites including:
 - a number of fixes for the arch-timer
 - introducing proper level-triggered semantics for the arch-timers
 - a series of patches to synchronously halt a guest (prerequisite for
   IRQ forwarding)
 - some tracepoint improvements
 - a tweak for the EL2 panic handlers
 - some more VGIC cleanups getting rid of redundant state
 
 x86: quite a few changes:
 
 - support for VT-d posted interrupts (i.e. PCI devices can inject
 interrupts directly into vCPUs).  This introduces a new component (in
 virt/lib/) that connects VFIO and KVM together.  The same infrastructure
 will be used for ARM interrupt forwarding as well.
 
 - more Hyper-V features, though the main one Hyper-V synthetic interrupt
 controller will have to wait for 4.5.  These will let KVM expose Hyper-V
 devices.
 
 - nested virtualization now supports VPID (same as PCID but for vCPUs)
 which makes it quite a bit faster
 
 - for future hardware that supports NVDIMM, there is support for clflushopt,
 clwb, pcommit
 
 - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in
 userspace, which reduces the attack surface of the hypervisor
 
 - obligatory smattering of SMM fixes
 
 - on the guest side, stable scheduler clock support was rewritten to not
 require help from the hypervisor.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.4.

  s390:
     A bunch of fixes and optimizations for interrupt and time handling.

  PPC:
     Mostly bug fixes.

  ARM:
     No big features, but many small fixes and prerequisites including:

      - a number of fixes for the arch-timer

      - introducing proper level-triggered semantics for the arch-timers

      - a series of patches to synchronously halt a guest (prerequisite
        for IRQ forwarding)

      - some tracepoint improvements

      - a tweak for the EL2 panic handlers

      - some more VGIC cleanups getting rid of redundant state

  x86:
     Quite a few changes:

      - support for VT-d posted interrupts (i.e. PCI devices can inject
        interrupts directly into vCPUs).  This introduces a new
        component (in virt/lib/) that connects VFIO and KVM together.
        The same infrastructure will be used for ARM interrupt
        forwarding as well.

      - more Hyper-V features, though the main one Hyper-V synthetic
        interrupt controller will have to wait for 4.5.  These will let
        KVM expose Hyper-V devices.

      - nested virtualization now supports VPID (same as PCID but for
        vCPUs) which makes it quite a bit faster

      - for future hardware that supports NVDIMM, there is support for
        clflushopt, clwb, pcommit

      - support for "split irqchip", i.e.  LAPIC in kernel +
        IOAPIC/PIC/PIT in userspace, which reduces the attack surface of
        the hypervisor

      - obligatory smattering of SMM fixes

      - on the guest side, stable scheduler clock support was rewritten
        to not require help from the hypervisor"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits)
  KVM: VMX: Fix commit which broke PML
  KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0()
  KVM: x86: allow RSM from 64-bit mode
  KVM: VMX: fix SMEP and SMAP without EPT
  KVM: x86: move kvm_set_irq_inatomic to legacy device assignment
  KVM: device assignment: remove pointless #ifdefs
  KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic
  KVM: x86: zero apic_arb_prio on reset
  drivers/hv: share Hyper-V SynIC constants with userspace
  KVM: x86: handle SMBASE as physical address in RSM
  KVM: x86: add read_phys to x86_emulate_ops
  KVM: x86: removing unused variable
  KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs
  KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
  KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings
  KVM: arm/arm64: Optimize away redundant LR tracking
  KVM: s390: use simple switch statement as multiplexer
  KVM: s390: drop useless newline in debugging data
  KVM: s390: SCA must not cross page boundaries
  KVM: arm: Do not indent the arguments of DECLARE_BITMAP
  ...
2015-11-05 16:26:26 -08:00
Paul Mackerras
23316316c1 powerpc: Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8"
This reverts commit 9678cdaae9 ("Use the POWER8 Micro Partition
Prefetch Engine in KVM HV on POWER8") because the original commit had
multiple, partly self-cancelling bugs, that could cause occasional
memory corruption.

In fact the logmpp instruction was incorrectly using register r0 as the
source of the buffer address and operation code, and depending on what
was in r0, it would either do nothing or corrupt the 64k page pointed to
by r0.

The logmpp instruction encoding and the operation code definitions could
be corrected, but then there is the problem that there is no clearly
defined way to know when the hardware has finished writing to the
buffer.

The original commit attempted to work around this by aborting the
write-out before starting the prefetch, but this is ineffective in the
case where the virtual core is now executing on a different physical
core from the one where the write-out was initiated.

These problems plus advice from the hardware designers not to use the
function (since the measured performance improvement from using the
feature was actually mostly negative), mean that reverting the code is
the best option.

Fixes: 9678cdaae9 ("Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8")
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-21 20:50:30 +11:00
Gautham R. Shenoy
70aa3961a1 KVM: PPC: Book3S HV: Handle H_DOORBELL on the guest exit path
Currently a CPU running a guest can receive a H_DOORBELL in the
following two cases:
1) When the CPU is napping due to CEDE or there not being a guest
vcpu.
2) The CPU is running the guest vcpu.

Case 1), the doorbell message is not cleared since we were waking up
from nap. Hence when the EE bit gets set on transition from guest to
host, the H_DOORBELL interrupt is delivered to the host and the
corresponding handler is invoked.

However in Case 2), the message gets cleared by the action of taking
the H_DOORBELL interrupt. Since the CPU was running a guest, instead
of invoking the doorbell handler, the code invokes the second-level
interrupt handler to switch the context from the guest to the host. At
this point the setting of the EE bit doesn't result in the CPU getting
the doorbell interrupt since it has already been delivered once. So,
the handler for this doorbell is never invoked!

This causes softlockups if the missed DOORBELL was an IPI sent from a
sibling subcore on the same CPU.

This patch fixes it by explitly invoking the doorbell handler on the
exit path if the exit reason is H_DOORBELL similar to the way an
EXTERNAL interrupt is handled. Since this will also handle Case 1), we
can unconditionally clear the doorbell message in
kvmppc_check_wake_reason.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-21 16:31:52 +11:00
Nikunj A Dadhania
bfec5c2cc0 KVM: PPC: Implement extension to report number of memslots
QEMU assumes 32 memslots if this extension is not implemented. Although,
current value of KVM_USER_MEM_SLOTS is 32, once KVM_USER_MEM_SLOTS
changes QEMU would take a wrong value.

Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-21 16:31:46 +11:00
Paul Mackerras
c64dfe2af3 KVM: PPC: Book3S HV: Make H_REMOVE return correct HPTE value for absent HPTEs
This fixes a bug where the old HPTE value returned by H_REMOVE has
the valid bit clear if the HPTE was an absent HPTE, as happens for
HPTEs for emulated MMIO pages and for RAM pages that have been paged
out by the host.  If the absent bit is set, we clear it and set the
valid bit, because from the guest's point of view, the HPTE is valid.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-21 16:25:06 +11:00
Paul Mackerras
572abd563b KVM: PPC: Book3S HV: Don't fall back to smaller HPT size in allocation ioctl
Currently the KVM_PPC_ALLOCATE_HTAB will try to allocate the requested
size of HPT, and if that is not possible, then try to allocate smaller
sizes (by factors of 2) until either a minimum is reached or the
allocation succeeds.  This is not ideal for userspace, particularly in
migration scenarios, where the destination VM really does require the
size requested.  Also, the minimum HPT size of 256kB may be
insufficient for the guest to run successfully.

This removes the fallback to smaller sizes on allocation failure for
the KVM_PPC_ALLOCATE_HTAB ioctl.  The fallback still exists for the
case where the HPT is allocated at the time the first VCPU is run, if
no HPT has been allocated by ioctl by that time.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-21 16:24:57 +11:00
Mahesh Salgaonkar
966d713e86 KVM: PPC: Book3S HV: Deliver machine check with MSR(RI=0) to guest as MCE
For the machine check interrupt that happens while we are in the guest,
kvm layer attempts the recovery, and then delivers the machine check interrupt
directly to the guest if recovery fails. On successful recovery we go back to
normal functioning of the guest. But there can be cases where a machine check
interrupt can happen with MSR(RI=0) while we are in the guest. This means
MC interrupt is unrecoverable and we have to deliver a machine check to the
guest since the machine check interrupt might have trashed valid values in
SRR0/1. The current implementation do not handle this case, causing guest
to crash with Bad kernel stack pointer instead of machine check oops message.

[26281.490060] Bad kernel stack pointer 3fff9ccce5b0 at c00000000000490c
[26281.490434] Oops: Bad kernel stack pointer, sig: 6 [#1]
[26281.490472] SMP NR_CPUS=2048 NUMA pSeries

This patch fixes this issue by checking MSR(RI=0) in KVM layer and forwarding
unrecoverable interrupt to guest which then panics with proper machine check
Oops message.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-16 11:53:47 +11:00
Tudor Laurentiu
224f363246 KVM: PPC: e500: fix couple of shift operations on 64 bits
Fix couple of cases where we shift left a 32-bit
value thus might get truncated results on 64-bit
targets.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Suggested-by: Scott Wood <scotttwood@freescale.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-15 15:59:19 +11:00
Tudor Laurentiu
2daab50e17 KVM: PPC: e500: Emulate TMCFG0 TMRN register
Emulate TMCFG0 TMRN register exposing one HW thread per vcpu.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[Laurentiu.Tudor@freescale.com: rebased on latest kernel, use
 define instead of hardcoded value, moved code in own function]
Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Acked-by: Scott Wood <scotttwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-15 15:58:16 +11:00
Andrzej Hajda
d4cd4f9586 KVM: PPC: e500: fix handling local_sid_lookup result
The function can return negative value.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/assign_signed_to_unsigned.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2046107

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-15 15:58:16 +11:00
Aneesh Kumar K.V
891121e6c0 powerpc/mm: Differentiate between hugetlb and THP during page walk
We need to properly identify whether a hugepage is an explicit or
a transparent hugepage in follow_huge_addr(). We used to depend
on hugepage shift argument to do that. But in some case that can
result in wrong results. For ex:

On finding a transparent hugepage we set hugepage shift to PMD_SHIFT.
But we can end up clearing the thp pte, via pmdp_huge_get_and_clear.
We do prevent reusing the pfn page via the usage of
kick_all_cpus_sync(). But that happens after we updated the pte to 0.
Hence in follow_huge_addr() we can find hugepage shift set, but transparent
huge page check fail for a thp pte.

NOTE: We fixed a variant of this race against thp split in commit
691e95fd73
("powerpc/mm/thp: Make page table walk safe against thp split/collapse")

Without this patch, we may hit the BUG_ON(flags & FOLL_GET) in
follow_page_mask occasionally.

In the long term, we may want to switch ppc64 64k page size config to
enable CONFIG_ARCH_WANT_GENERAL_HUGETLB

Reported-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-12 15:30:09 +11:00
Thomas Huth
3eb4ee6825 KVM: PPC: Book3S: Take the kvm->srcu lock in kvmppc_h_logical_ci_load/store()
Access to the kvm->buses (like with the kvm_io_bus_read() and -write()
functions) has to be protected via the kvm->srcu lock.
The kvmppc_h_logical_ci_load() and -store() functions are missing
this lock so far, so let's add it there, too.
This fixes the problem that the kernel reports "suspicious RCU usage"
when lock debugging is enabled.

Cc: stable@vger.kernel.org # v4.1+
Fixes: 99342cf804
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-21 09:05:15 +10:00
Gautham R. Shenoy
7e022e717f KVM: PPC: Book3S HV: Pass the correct trap argument to kvmhv_commence_exit
In guest_exit_cont we call kvmhv_commence_exit which expects the trap
number as the argument. However r3 doesn't contain the trap number at
this point and as a result we would be calling the function with a
spurious trap number.

Fix this by copying r12 into r3 before calling kvmhv_commence_exit as
r12 contains the trap number.

Cc: stable@vger.kernel.org # v4.1+
Fixes: eddb60fb14
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-21 09:05:12 +10:00
Paul Mackerras
5fc3e64f94 KVM: PPC: Book3S HV: Fix handling of interrupted VCPUs
This fixes a bug which results in stale vcore pointers being left in
the per-cpu preempted vcore lists when a VM is destroyed.  The result
of the stale vcore pointers is usually either a crash or a lockup
inside collect_piggybacks() when another VM is run.  A typical
lockup message looks like:

[  472.161074] NMI watchdog: BUG: soft lockup - CPU#24 stuck for 22s! [qemu-system-ppc:7039]
[  472.161204] Modules linked in: kvm_hv kvm_pr kvm xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 tun ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw ses enclosure shpchp rtc_opal i2c_opal powernv_rng binfmt_misc dm_service_time scsi_dh_alua radeon i2c_algo_bit drm_kms_helper ttm drm tg3 ptp pps_core cxgb3 ipr i2c_core mdio dm_multipath [last unloaded: kvm_hv]
[  472.162111] CPU: 24 PID: 7039 Comm: qemu-system-ppc Not tainted 4.2.0-kvm+ #49
[  472.162187] task: c000001e38512750 ti: c000001e41bfc000 task.ti: c000001e41bfc000
[  472.162262] NIP: c00000000096b094 LR: c00000000096b08c CTR: c000000000111130
[  472.162337] REGS: c000001e41bff520 TRAP: 0901   Not tainted  (4.2.0-kvm+)
[  472.162399] MSR: 9000000100009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 24848844  XER: 00000000
[  472.162588] CFAR: c00000000096b0ac SOFTE: 1
GPR00: c000000000111170 c000001e41bff7a0 c00000000127df00 0000000000000001
GPR04: 0000000000000003 0000000000000001 0000000000000000 0000000000874821
GPR08: c000001e41bff8e0 0000000000000001 0000000000000000 d00000000efde740
GPR12: c000000000111130 c00000000fdae400
[  472.163053] NIP [c00000000096b094] _raw_spin_lock_irqsave+0xa4/0x130
[  472.163117] LR [c00000000096b08c] _raw_spin_lock_irqsave+0x9c/0x130
[  472.163179] Call Trace:
[  472.163206] [c000001e41bff7a0] [c000001e41bff7f0] 0xc000001e41bff7f0 (unreliable)
[  472.163295] [c000001e41bff7e0] [c000000000111170] __wake_up+0x40/0x90
[  472.163375] [c000001e41bff830] [d00000000efd6fc0] kvmppc_run_core+0x1240/0x1950 [kvm_hv]
[  472.163465] [c000001e41bffa30] [d00000000efd8510] kvmppc_vcpu_run_hv+0x5a0/0xd90 [kvm_hv]
[  472.163559] [c000001e41bffb70] [d00000000e9318a4] kvmppc_vcpu_run+0x44/0x60 [kvm]
[  472.163653] [c000001e41bffba0] [d00000000e92e674] kvm_arch_vcpu_ioctl_run+0x64/0x170 [kvm]
[  472.163745] [c000001e41bffbe0] [d00000000e9263a8] kvm_vcpu_ioctl+0x538/0x7b0 [kvm]
[  472.163834] [c000001e41bffd40] [c0000000002d0f50] do_vfs_ioctl+0x480/0x7c0
[  472.163910] [c000001e41bffde0] [c0000000002d1364] SyS_ioctl+0xd4/0xf0
[  472.163986] [c000001e41bffe30] [c000000000009260] system_call+0x38/0xd0
[  472.164060] Instruction dump:
[  472.164098] ebc1fff0 ebe1fff8 7c0803a6 4e800020 60000000 60000000 60420000 8bad02e2
[  472.164224] 7fc3f378 4b6a57c1 60000000 7c210b78 <e92d0000> 89290009 792affe3 40820070

The bug is that kvmppc_run_vcpu does not correctly handle the case
where a vcpu task receives a signal while its guest vcpu is executing
in the guest as a result of being piggy-backed onto the execution of
another vcore.  In that case we need to wait for the vcpu to finish
executing inside the guest, and then remove this vcore from the
preempted vcores list.  That way, we avoid leaving this vcpu's vcore
on the preempted vcores list when the vcpu gets interrupted.

Fixes: ec25716508
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-21 09:00:47 +10:00
Paolo Bonzini
62bea5bff4 KVM: add halt_attempted_poll to VCPU stats
This new statistic can help diagnosing VCPUs that, for any reason,
trigger bad behavior of halt_poll_ns autotuning.

For example, say halt_poll_ns = 480000, and wakeups are spaced exactly
like 479us, 481us, 479us, 481us. Then KVM always fails polling and wastes
10+20+40+80+160+320+480 = 1110 microseconds out of every
479+481+479+481+479+481+479 = 3359 microseconds. The VCPU then
is consuming about 30% more CPU than it would use without
polling.  This would show as an abnormally high number of
attempted polling compared to the successful polls.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com<
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-16 12:17:00 +02:00
Linus Torvalds
519f526d39 ARM:
- Full debug support for arm64
 - Active state switching for timer interrupts
 - Lazy FP/SIMD save/restore for arm64
 - Generic ARMv8 target
 
 PPC:
 - Book3S: A few bug fixes
 - Book3S: Allow micro-threading on POWER8
 
 x86:
 - Compiler warnings
 
 Generic:
 - Adaptive polling for guest halt
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more kvm updates from Paolo Bonzini:
 "ARM:
   - Full debug support for arm64
   - Active state switching for timer interrupts
   - Lazy FP/SIMD save/restore for arm64
   - Generic ARMv8 target

  PPC:
   - Book3S: A few bug fixes
   - Book3S: Allow micro-threading on POWER8

  x86:
   - Compiler warnings

  Generic:
   - Adaptive polling for guest halt"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (49 commits)
  kvm: irqchip: fix memory leak
  kvm: move new trace event outside #ifdef CONFIG_KVM_ASYNC_PF
  KVM: trace kvm_halt_poll_ns grow/shrink
  KVM: dynamic halt-polling
  KVM: make halt_poll_ns per-vCPU
  Silence compiler warning in arch/x86/kvm/emulate.c
  kvm: compile process_smi_save_seg_64() only for x86_64
  KVM: x86: avoid uninitialized variable warning
  KVM: PPC: Book3S: Fix typo in top comment about locking
  KVM: PPC: Book3S: Fix size of the PSPB register
  KVM: PPC: Book3S HV: Exit on H_DOORBELL if HOST_IPI is set
  KVM: PPC: Book3S HV: Fix race in starting secondary threads
  KVM: PPC: Book3S: correct width in XER handling
  KVM: PPC: Book3S HV: Fix preempted vcore stolen time calculation
  KVM: PPC: Book3S HV: Fix preempted vcore list locking
  KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MOD
  KVM: PPC: Book3S HV: Fix bug in dirty page tracking
  KVM: PPC: Book3S HV: Fix race in reading change bit when removing HPTE
  KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8
  KVM: PPC: Book3S HV: Make use of unused threads when running guests
  ...
2015-09-10 16:42:49 -07:00
Greg Kurz
4e33d1f0a1 KVM: PPC: Book3S: Fix typo in top comment about locking
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-04 07:28:05 +10:00
Gautham R. Shenoy
06554d9f6c KVM: PPC: Book3S HV: Exit on H_DOORBELL if HOST_IPI is set
The code that handles the case when we receive a H_DOORBELL interrupt
has a comment which says "Hypervisor doorbell - exit only if host IPI
flag set".  However, the current code does not actually check if the
host IPI flag is set.  This is due to a comparison instruction that
got missed.

As a result, the current code performs the exit to host only
if some sibling thread or a sibling sub-core is exiting to the
host.  This implies that, an IPI sent to a sibling core in
(subcores-per-core != 1) mode will be missed by the host unless the
sibling core is on the exit path to the host.

This patch adds the missing comparison operation which will ensure
that when HOST_IPI flag is set, we unconditionally exit to the host.

Fixes: 66feed61cd
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03 16:08:34 +10:00
Gautham R. Shenoy
7f23532866 KVM: PPC: Book3S HV: Fix race in starting secondary threads
The current dynamic micro-threading code has a race due to which a
secondary thread naps when it is supposed to be running a vcpu. As a
side effect of this, on a guest exit, the primary thread in
kvmppc_wait_for_nap() finds that this secondary thread hasn't cleared
its vcore pointer. This results in "CPU X seems to be stuck!"
warnings.

The race is possible since the primary thread on exiting the guests
only waits for all the secondaries to clear its vcore pointer. It
subsequently expects the secondary threads to enter nap while it
unsplits the core. A secondary thread which hasn't yet entered the nap
will loop in kvm_no_guest until its vcore pointer and the do_nap flag
are unset. Once the core has been unsplit, a new vcpu thread can grab
the core and set the do_nap flag *before* setting the vcore pointers
of the secondary. As a result, the secondary thread will now enter nap
via kvm_unsplit_nap instead of running the guest vcpu.

Fix this by setting the do_nap flag after setting the vcore pointer in
the PACA of the secondary in kvmppc_run_core. Also, ensure that a
secondary thread doesn't nap in kvm_unsplit_nap when the vcore pointer
in its PACA struct is set.

Fixes: b4deba5c41
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03 16:07:42 +10:00
Linus Torvalds
089b669506 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual stuff from trivial tree for 4.3 (kerneldoc updates, printk()
  fixes, Documentation and MAINTAINERS updates)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  MAINTAINERS: update my e-mail address
  mod_devicetable: add space before */
  scsi: a100u2w: trivial typo in printk
  i2c: Fix typo in i2c-bfin-twi.c
  treewide: fix typos in comment blocks
  Doc: fix trivial typo in SubmittingPatches
  proportions: Spelling s/consitent/consistent/
  dm: Spelling s/consitent/consistent/
  aic7xxx: Fix typo in error message
  pcmcia: Fix typo in locking documentation
  scsi/arcmsr: Fix typos in error log
  drm/nouveau/gr: Fix typo in nv10.c
  [SCSI] Fix printk typos in drivers/scsi
  staging: comedi: Grammar s/Enable support a/Enable support for a/
  Btrfs: Spelling s/consitent/consistent/
  README: GTK+ is a acronym
  ASoC: omap: Fix typo in config option description
  mm: tlb.c: Fix error message
  ntfs: super.c: Fix error log
  fix typo in Documentation/SubmittingPatches
  ...
2015-09-01 18:46:42 -07:00
Sam bobroff
c63517c2e3 KVM: PPC: Book3S: correct width in XER handling
In 64 bit kernels, the Fixed Point Exception Register (XER) is a 64
bit field (e.g. in kvm_regs and kvm_vcpu_arch) and in most places it is
accessed as such.

This patch corrects places where it is accessed as a 32 bit field by a
64 bit kernel.  In some cases this is via a 32 bit load or store
instruction which, depending on endianness, will cause either the
lower or upper 32 bits to be missed.  In another case it is cast as a
u32, causing the upper 32 bits to be cleared.

This patch corrects those places by extending the access methods to
64 bits.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:19 +02:00
Paul Mackerras
563a1e93af KVM: PPC: Book3S HV: Fix preempted vcore stolen time calculation
Whenever a vcore state is VCORE_PREEMPT we need to be counting stolen
time for it.  This currently isn't the case when we have a vcore that
no longer has any runnable threads in it but still has a runner task,
so we do an explicit call to kvmppc_core_start_stolen() in that case.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:19 +02:00
Paul Mackerras
402813fe39 KVM: PPC: Book3S HV: Fix preempted vcore list locking
When a vcore gets preempted, we put it on the preempted vcore list for
the current CPU.  The runner task then calls schedule() and comes back
some time later and takes itself off the list.  We need to be careful
to lock the list that it was put onto, which may not be the list for the
current CPU since the runner task may have moved to another CPU.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:19 +02:00
Paul Mackerras
cdeee51842 KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MOD
This adds implementations for the H_CLEAR_REF (test and clear reference
bit) and H_CLEAR_MOD (test and clear changed bit) hypercalls.

When clearing the reference or change bit in the guest view of the HPTE,
we also have to clear it in the real HPTE so that we can detect future
references or changes.  When we do so, we transfer the R or C bit value
to the rmap entry for the underlying host page so that kvm_age_hva_hv(),
kvm_test_age_hva_hv() and kvmppc_hv_get_dirty_log() know that the page
has been referenced and/or changed.

These hypercalls are not used by Linux guests.  These implementations
have been tested using a FreeBSD guest.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:18 +02:00
Paul Mackerras
08fe1e7bd2 KVM: PPC: Book3S HV: Fix bug in dirty page tracking
This fixes a bug in the tracking of pages that get modified by the
guest.  If the guest creates a large-page HPTE, writes to memory
somewhere within the large page, and then removes the HPTE, we only
record the modified state for the first normal page within the large
page, when in fact the guest might have modified some other normal
page within the large page.

To fix this we use some unused bits in the rmap entry to record the
order (log base 2) of the size of the page that was modified, when
removing an HPTE.  Then in kvm_test_clear_dirty_npages() we use that
order to return the correct number of modified pages.

The same thing could in principle happen when removing a HPTE at the
host's request, i.e. when paging out a page, except that we never
page out large pages, and the guest can only create large-page HPTEs
if the guest RAM is backed by large pages.  However, we also fix
this case for the sake of future-proofing.

The reference bit is also subject to the same loss of information.  We
don't make the same fix here for the reference bit because there isn't
an interface for userspace to find out which pages the guest has
referenced, whereas there is one for userspace to find out which pages
the guest has modified.  Because of this loss of information, the
kvm_age_hva_hv() and kvm_test_age_hva_hv() functions might incorrectly
say that a page has not been referenced when it has, but that doesn't
matter greatly because we never page or swap out large pages.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:18 +02:00
Paul Mackerras
1e5bf454f5 KVM: PPC: Book3S HV: Fix race in reading change bit when removing HPTE
The reference (R) and change (C) bits in a HPT entry can be set by
hardware at any time up until the HPTE is invalidated and the TLB
invalidation sequence has completed.  This means that when removing
a HPTE, we need to read the HPTE after the invalidation sequence has
completed in order to obtain reliable values of R and C.  The code
in kvmppc_do_h_remove() used to do this.  However, commit 6f22bd3265
("KVM: PPC: Book3S HV: Make HTAB code LE host aware") removed the
read after invalidation as a side effect of other changes.  This
restores the read of the HPTE after invalidation.

The user-visible effect of this bug would be that when migrating a
guest, there is a small probability that a page modified by the guest
and then unmapped by the guest might not get re-transmitted and thus
the destination might end up with a stale copy of the page.

Fixes: 6f22bd3265
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:18 +02:00
Paul Mackerras
b4deba5c41 KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8
This builds on the ability to run more than one vcore on a physical
core by using the micro-threading (split-core) modes of the POWER8
chip.  Previously, only vcores from the same VM could be run together,
and (on POWER8) only if they had just one thread per core.  With the
ability to split the core on guest entry and unsplit it on guest exit,
we can run up to 8 vcpu threads from up to 4 different VMs, and we can
run multiple vcores with 2 or 4 vcpus per vcore.

Dynamic micro-threading is only available if the static configuration
of the cores is whole-core mode (unsplit), and only on POWER8.

To manage this, we introduce a new kvm_split_mode struct which is
shared across all of the subcores in the core, with a pointer in the
paca on each thread.  In addition we extend the core_info struct to
have information on each subcore.  When deciding whether to add a
vcore to the set already on the core, we now have two possibilities:
(a) piggyback the vcore onto an existing subcore, or (b) start a new
subcore.

Currently, when any vcpu needs to exit the guest and switch to host
virtual mode, we interrupt all the threads in all subcores and switch
the core back to whole-core mode.  It may be possible in future to
allow some of the subcores to keep executing in the guest while
subcore 0 switches to the host, but that is not implemented in this
patch.

This adds a module parameter called dynamic_mt_modes which controls
which micro-threading (split-core) modes the code will consider, as a
bitmap.  In other words, if it is 0, no micro-threading mode is
considered; if it is 2, only 2-way micro-threading is considered; if
it is 4, only 4-way, and if it is 6, both 2-way and 4-way
micro-threading mode will be considered.  The default is 6.

With this, we now have secondary threads which are the primary thread
for their subcore and therefore need to do the MMU switch.  These
threads will need to be started even if they have no vcpu to run, so
we use the vcore pointer in the PACA rather than the vcpu pointer to
trigger them.

It is now possible for thread 0 to find that an exit has been
requested before it gets to switch the subcore state to the guest.  In
that case we haven't added the guest's timebase offset to the
timebase, so we need to be careful not to subtract the offset in the
guest exit path.  In fact we just skip the whole path that switches
back to host context, since we haven't switched to the guest context.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:17 +02:00
Paul Mackerras
ec25716508 KVM: PPC: Book3S HV: Make use of unused threads when running guests
When running a virtual core of a guest that is configured with fewer
threads per core than the physical cores have, the extra physical
threads are currently unused.  This makes it possible to use them to
run one or more other virtual cores from the same guest when certain
conditions are met.  This applies on POWER7, and on POWER8 to guests
with one thread per virtual core.  (It doesn't apply to POWER8 guests
with multiple threads per vcore because they require a 1-1 virtual to
physical thread mapping in order to be able to use msgsndp and the
TIR.)

The idea is that we maintain a list of preempted vcores for each
physical cpu (i.e. each core, since the host runs single-threaded).
Then, when a vcore is about to run, it checks to see if there are
any vcores on the list for its physical cpu that could be
piggybacked onto this vcore's execution.  If so, those additional
vcores are put into state VCORE_PIGGYBACK and their runnable VCPU
threads are started as well as the original vcore, which is called
the master vcore.

After the vcores have exited the guest, the extra ones are put back
onto the preempted list if any of their VCPUs are still runnable and
not idle.

This means that vcpu->arch.ptid is no longer necessarily the same as
the physical thread that the vcpu runs on.  In order to make it easier
for code that wants to send an IPI to know which CPU to target, we
now store that in a new field in struct vcpu_arch, called thread_cpu.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:17 +02:00
Tudor Laurentiu
845ac985cf KVM: PPC: add missing pt_regs initialization
On this switch branch the regs initialization
doesn't happen so add it.
This was found with the help of a static
code analysis tool.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:17 +02:00
Thomas Huth
5358a96341 KVM: PPC: Fix warnings from sparse
When compiling the KVM code for POWER with "make C=1", sparse
complains about functions missing proper prototypes and a 64-bit
constant missing the ULL prefix. Let's fix this by making the
functions static or by including the proper header with the
prototypes, and by appending a ULL prefix to the constant
PPC_MPPE_ADDRESS_MASK.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:16 +02:00
Thomas Huth
129fd4233b KVM: PPC: Remove PPC970 from KVM_BOOK3S_64_HV text in Kconfig
Since the PPC970 support has been removed from the kvm-hv kernel
module recently, we should also reflect this change in the help
text of the corresponding Kconfig option.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:16 +02:00
Tudor Laurentiu
f5ffe330f5 KVM: PPC: fix suspicious use of conditional operator
This was signaled by a static code analysis tool.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Reviewed-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:16 +02:00
Laurent Pinchart
60acc4ebe7 treewide: Fix typo compatability -> compatibility
Even though 'compatability' has a dedicated entry in the Wiktionary,
it's listed as 'Mispelling of compatibility'. Fix it.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> for the atomic_helper.c
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2015-08-07 14:01:39 +02:00
Konstantin Khlebnikov
c56dadf397 sched/preempt, powerpc, kvm: Use need_resched() instead of should_resched()
Function should_resched() is equal to (!preempt_count() && need_resched()).
In preemptive kernel preempt_count here is non-zero because of vc->lock.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150715095203.12246.72922.stgit@buzz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-03 12:21:24 +02:00
Linus Torvalds
4e241557fc The bulk of the changes here is for x86. And for once it's not
for silicon that no one owns: these are really new features for
 everyone.
 
 * ARM: several features are in progress but missed the 4.2 deadline.
 So here is just a smattering of bug fixes, plus enabling the VFIO
 integration.
 
 * s390: Some fixes/refactorings/optimizations, plus support for
 2GB pages.
 
 * x86: 1) host and guest support for marking kvmclock as a stable
 scheduler clock. 2) support for write combining. 3) support for
 system management mode, needed for secure boot in guests. 4) a bunch
 of cleanups required for 2+3.  5) support for virtualized performance
 counters on AMD; 6) legacy PCI device assignment is deprecated and
 defaults to "n" in Kconfig; VFIO replaces it.  On top of this there are
 also bug fixes and eager FPU context loading for FPU-heavy guests.
 
 * Common code: Support for multiple address spaces; for now it is
 used only for x86 SMM but the s390 folks also have plans.
 
 There are some x86 conflicts, one with the rc8 pull request and
 the rest with Ingo's FPU rework.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull first batch of KVM updates from Paolo Bonzini:
 "The bulk of the changes here is for x86.  And for once it's not for
  silicon that no one owns: these are really new features for everyone.

  Details:

   - ARM:
        several features are in progress but missed the 4.2 deadline.
        So here is just a smattering of bug fixes, plus enabling the
        VFIO integration.

   - s390:
        Some fixes/refactorings/optimizations, plus support for 2GB
        pages.

   - x86:
        * host and guest support for marking kvmclock as a stable
          scheduler clock.
        * support for write combining.
        * support for system management mode, needed for secure boot in
          guests.
        * a bunch of cleanups required for the above
        * support for virtualized performance counters on AMD
        * legacy PCI device assignment is deprecated and defaults to "n"
          in Kconfig; VFIO replaces it

        On top of this there are also bug fixes and eager FPU context
        loading for FPU-heavy guests.

   - Common code:
        Support for multiple address spaces; for now it is used only for
        x86 SMM but the s390 folks also have plans"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits)
  KVM: s390: clear floating interrupt bitmap and parameters
  KVM: x86/vPMU: Enable PMU handling for AMD PERFCTRn and EVNTSELn MSRs
  KVM: x86/vPMU: Implement AMD vPMU code for KVM
  KVM: x86/vPMU: Define kvm_pmu_ops to support vPMU function dispatch
  KVM: x86/vPMU: introduce kvm_pmu_msr_idx_to_pmc
  KVM: x86/vPMU: reorder PMU functions
  KVM: x86/vPMU: whitespace and stylistic adjustments in PMU code
  KVM: x86/vPMU: use the new macros to go between PMC, PMU and VCPU
  KVM: x86/vPMU: introduce pmu.h header
  KVM: x86/vPMU: rename a few PMU functions
  KVM: MTRR: do not map huge page for non-consistent range
  KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type
  KVM: MTRR: introduce mtrr_for_each_mem_type
  KVM: MTRR: introduce fixed_mtrr_addr_* functions
  KVM: MTRR: sort variable MTRRs
  KVM: MTRR: introduce var_mtrr_range
  KVM: MTRR: introduce fixed_mtrr_segment table
  KVM: MTRR: improve kvm_mtrr_get_guest_memory_type
  KVM: MTRR: do not split 64 bits MSR content
  KVM: MTRR: clean up mtrr default type
  ...
2015-06-24 09:36:49 -07:00
Linus Torvalds
08d183e3c1 powerpc updates for 4.2
- Disable the 32-bit vdso when building LE, so we can build with a 64-bit only
    toolchain.
  - EEH fixes from Gavin & Richard.
  - Enable the sys_kcmp syscall from Laurent.
  - Sysfs control for fastsleep workaround from Shreyas.
  - Expose OPAL events as an irq chip by Alistair.
  - MSI ops moved to pci_controller_ops by Daniel.
  - Fix for kernel to userspace backtraces for perf from Anton.
  - Merge pseries and pseries_le defconfigs from Cyril.
  - CXL in-kernel API from Mikey.
  - OPAL prd driver from Jeremy.
  - Fix for DSCR handling & tests from Anshuman.
  - Powernv flash mtd driver from Cyril.
  - Dynamic DMA Window support on powernv from Alexey.
  - LLVM clang fixes & workarounds from Anton.
  - Reworked version of the patch to abort syscalls when transactional.
  - Fix the swap encoding to support 4TB, from Aneesh.
  - Various fixes as usual.
  - Freescale updates from Scott: Highlights include more 8xx optimizations, an
    e6500 hugetlb optimization, QMan device tree nodes, t1024/t1023 support, and
    various fixes and cleanup.
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Merge tag 'powerpc-4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:

 - disable the 32-bit vdso when building LE, so we can build with a
   64-bit only toolchain.

 - EEH fixes from Gavin & Richard.

 - enable the sys_kcmp syscall from Laurent.

 - sysfs control for fastsleep workaround from Shreyas.

 - expose OPAL events as an irq chip by Alistair.

 - MSI ops moved to pci_controller_ops by Daniel.

 - fix for kernel to userspace backtraces for perf from Anton.

 - merge pseries and pseries_le defconfigs from Cyril.

 - CXL in-kernel API from Mikey.

 - OPAL prd driver from Jeremy.

 - fix for DSCR handling & tests from Anshuman.

 - Powernv flash mtd driver from Cyril.

 - dynamic DMA Window support on powernv from Alexey.

 - LLVM clang fixes & workarounds from Anton.

 - reworked version of the patch to abort syscalls when transactional.

 - fix the swap encoding to support 4TB, from Aneesh.

 - various fixes as usual.

 - Freescale updates from Scott: Highlights include more 8xx
   optimizations, an e6500 hugetlb optimization, QMan device tree nodes,
   t1024/t1023 support, and various fixes and cleanup.

* tag 'powerpc-4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (180 commits)
  cxl: Fix typo in debug print
  cxl: Add CXL_KERNEL_API config option
  powerpc/powernv: Fix wrong IOMMU table in pnv_ioda_setup_bus_dma()
  powerpc/mm: Change the swap encoding in pte.
  powerpc/mm: PTE_RPN_MAX is not used, remove the same
  powerpc/tm: Abort syscalls in active transactions
  powerpc/iommu/ioda2: Enable compile with IOV=on and IOMMU_API=off
  powerpc/include: Add opal-prd to installed uapi headers
  powerpc/powernv: fix construction of opal PRD messages
  powerpc/powernv: Increase opal-irqchip initcall priority
  powerpc: Make doorbell check preemption safe
  powerpc/powernv: pnv_init_idle_states() should only run on powernv
  macintosh/nvram: Remove as unused
  powerpc: Don't use gcc specific options on clang
  powerpc: Don't use -mno-strict-align on clang
  powerpc: Only use -mtraceback=no, -mno-string and -msoft-float if toolchain supports it
  powerpc: Only use -mabi=altivec if toolchain supports it
  powerpc: Fix duplicate const clang warning in user access code
  vfio: powerpc/spapr: Support Dynamic DMA windows
  vfio: powerpc/spapr: Register memory and define IOMMU v2
  ...
2015-06-24 08:46:32 -07:00
Anshuman Khandual
1db365258a powerpc/kernel: Rename PACA_DSCR to PACA_DSCR_DEFAULT
PACA_DSCR offset macro tracks dscr_default element in the paca
structure. Better change the name of this macro to match that of the
data element it tracks. Makes the code more readable.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-06-07 19:29:00 +10:00
Paolo Bonzini
f36f3f2846 KVM: add "new" argument to kvm_arch_commit_memory_region
This lets the function access the new memory slot without going through
kvm_memslots and id_to_memslot.  It will simplify the code when more
than one address space will be supported.

Unfortunately, the "const"ness of the new argument must be casted
away in two places.  Fixing KVM to accept const struct kvm_memory_slot
pointers would require modifications in pretty much all architectures,
and is left for later.

Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-28 10:42:58 +02:00
Paolo Bonzini
09170a4942 KVM: const-ify uses of struct kvm_userspace_memory_region
Architecture-specific helpers are not supposed to muck with
struct kvm_userspace_memory_region contents.  Add const to
enforce this.

In order to eliminate the only write in __kvm_set_memory_region,
the cleaning of deleted slots is pulled up from update_memslots
to __kvm_set_memory_region.

Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26 12:40:13 +02:00
Paolo Bonzini
9f6b802978 KVM: use kvm_memslots whenever possible
kvm_memslots provides lockdep checking.  Use it consistently instead of
explicit dereferencing of kvm->memslots.

Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26 12:40:08 +02:00
Paolo Bonzini
a9b4fb7e79 Merge branch 'kvm-master' into kvm-next
Grab MPX bugfix, and fix conflicts against Rik's adaptive FPU
deactivation patch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-20 12:31:37 +02:00
Paul Mackerras
17d489019c KVM: PPC: Book3S HV: Fix list traversal in error case
This fixes a regression introduced in commit 25fedfca94, "KVM: PPC:
Book3S HV: Move vcore preemption point up into kvmppc_run_vcpu", which
leads to a user-triggerable oops.

In the case where we try to run a vcore on a physical core that is
not in single-threaded mode, or the vcore has too many threads for
the physical core, we iterate the list of runnable vcpus to make
each one return an EBUSY error to userspace.  Since this involves
taking each vcpu off the runnable_threads list for the vcore, we
need to use list_for_each_entry_safe rather than list_for_each_entry
to traverse the list.  Otherwise the kernel will crash with an oops
message like this:

Unable to handle kernel paging request for data at address 0x000fff88
Faulting instruction address: 0xd00000001e635dc8
Oops: Kernel access of bad area, sig: 11 [#2]
SMP NR_CPUS=1024 NUMA PowerNV
...
CPU: 48 PID: 91256 Comm: qemu-system-ppc Tainted: G      D        3.18.0 #1
task: c00000274e507500 ti: c0000027d1924000 task.ti: c0000027d1924000
NIP: d00000001e635dc8 LR: d00000001e635df8 CTR: c00000000011ba50
REGS: c0000027d19275b0 TRAP: 0300   Tainted: G      D         (3.18.0)
MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 22002824  XER: 00000000
CFAR: c000000000008468 DAR: 00000000000fff88 DSISR: 40000000 SOFTE: 1
GPR00: d00000001e635df8 c0000027d1927830 d00000001e64c850 0000000000000001
GPR04: 0000000000000001 0000000000000001 0000000000000000 0000000000000000
GPR08: 0000000000200200 0000000000000000 0000000000000000 d00000001e63e588
GPR12: 0000000000002200 c000000007dbc800 c000000fc7800000 000000000000000a
GPR16: fffffffffffffffc c000000fd5439690 c000000fc7801c98 0000000000000001
GPR20: 0000000000000003 c0000027d1927aa8 c000000fd543b348 c000000fd543b350
GPR24: 0000000000000000 c000000fa57f0000 0000000000000030 0000000000000000
GPR28: fffffffffffffff0 c000000fd543b328 00000000000fe468 c000000fd543b300
NIP [d00000001e635dc8] kvmppc_run_core+0x198/0x17c0 [kvm_hv]
LR [d00000001e635df8] kvmppc_run_core+0x1c8/0x17c0 [kvm_hv]
Call Trace:
[c0000027d1927830] [d00000001e635df8] kvmppc_run_core+0x1c8/0x17c0 [kvm_hv] (unreliable)
[c0000027d1927a30] [d00000001e638350] kvmppc_vcpu_run_hv+0x5b0/0xdd0 [kvm_hv]
[c0000027d1927b70] [d00000001e510504] kvmppc_vcpu_run+0x44/0x60 [kvm]
[c0000027d1927ba0] [d00000001e50d4a4] kvm_arch_vcpu_ioctl_run+0x64/0x170 [kvm]
[c0000027d1927be0] [d00000001e504be8] kvm_vcpu_ioctl+0x5e8/0x7a0 [kvm]
[c0000027d1927d40] [c0000000002d6720] do_vfs_ioctl+0x490/0x780
[c0000027d1927de0] [c0000000002d6ae4] SyS_ioctl+0xd4/0xf0
[c0000027d1927e30] [c000000000009358] syscall_exit+0x0/0x98
Instruction dump:
60000000 60420000 387e1b30 38800003 38a00001 38c00000 480087d9 e8410018
ebde1c98 7fbdf040 3bdee368 419e0048 <813e1b20> 939e1b18 2f890001 409effcc
---[ end trace 8cdf50251cca6680 ]---

Fixes: 25fedfca94
Signed-off-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-10 17:26:05 +02:00
Paolo Bonzini
e233d54d4d KVM: booke: use __kvm_guest_exit
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-07 11:28:22 +02:00
Christian Borntraeger
ccf73aaf5a KVM: arm/mips/x86/power use __kvm_guest_{enter|exit}
Use __kvm_guest_{enter|exit} instead of kvm_guest_{enter|exit}
where interrupts are disabled.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-07 11:28:22 +02:00
Michael Ellerman
433c5c20c5 powerpc/kvm: Fix SMP=n build error in book3s_xics.c
Commit 34cb7954c0 "Convert ICS mutex lock to spin lock" added an
include of asm/spinlock.h, which does not work in the SMP=n case.

It should instead include linux/spinlock.h

Fixes: 34cb7954c0 ("KVM: PPC: Book3S HV: Convert ICS mutex lock to spin lock")
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-29 08:06:32 +10:00
Linus Torvalds
63905bba5b powerpc fixes for 4.1
- Fix for mm_dec_nr_pmds() from Scott.
 - Fixes for oopses seen with KVM + THP from Aneesh.
 - Build fixes from Aneesh & Shreyas.
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Merge tag 'powerpc-4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc fixes from Michael Ellerman:

 - fix for mm_dec_nr_pmds() from Scott.

 - fixes for oopses seen with KVM + THP from Aneesh.

 - build fixes from Aneesh & Shreyas.

* tag 'powerpc-4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
  powerpc/mm: Fix build error with CONFIG_PPC_TRANSACTIONAL_MEM disabled
  powerpc/kvm: Fix ppc64_defconfig + PPC_POWERNV=n build error
  powerpc/mm/thp: Return pte address if we find trans_splitting.
  powerpc/mm/thp: Make page table walk safe against thp split/collapse
  KVM: PPC: Remove page table walk helpers
  KVM: PPC: Use READ_ONCE when dereferencing pte_t pointer
  powerpc/hugetlb: Call mm_dec_nr_pmds() in hugetlb_free_pmd_range()
2015-04-26 13:23:15 -07:00
Linus Torvalds
eadf16a912 This mostly includes the PPC changes for 4.1, which this time cover
Book3S HV only (debugging aids, minor performance improvements and some
 cleanups).  But there are also bug fixes and small cleanups for ARM,
 x86 and s390.
 
 The task_migration_notifier revert and real fix is still pending review,
 but I'll send it as soon as possible after -rc1.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull second batch of KVM changes from Paolo Bonzini:
 "This mostly includes the PPC changes for 4.1, which this time cover
  Book3S HV only (debugging aids, minor performance improvements and
  some cleanups).  But there are also bug fixes and small cleanups for
  ARM, x86 and s390.

  The task_migration_notifier revert and real fix is still pending
  review, but I'll send it as soon as possible after -rc1"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (29 commits)
  KVM: arm/arm64: check IRQ number on userland injection
  KVM: arm: irqfd: fix value returned by kvm_irq_map_gsi
  KVM: VMX: Preserve host CR4.MCE value while in guest mode.
  KVM: PPC: Book3S HV: Use msgsnd for signalling threads on POWER8
  KVM: PPC: Book3S HV: Translate kvmhv_commence_exit to C
  KVM: PPC: Book3S HV: Streamline guest entry and exit
  KVM: PPC: Book3S HV: Use bitmap of active threads rather than count
  KVM: PPC: Book3S HV: Use decrementer to wake napping threads
  KVM: PPC: Book3S HV: Don't wake thread with no vcpu on guest IPI
  KVM: PPC: Book3S HV: Get rid of vcore nap_count and n_woken
  KVM: PPC: Book3S HV: Move vcore preemption point up into kvmppc_run_vcpu
  KVM: PPC: Book3S HV: Minor cleanups
  KVM: PPC: Book3S HV: Simplify handling of VCPUs that need a VPA update
  KVM: PPC: Book3S HV: Accumulate timing information for real-mode code
  KVM: PPC: Book3S HV: Create debugfs file for each guest's HPT
  KVM: PPC: Book3S HV: Add ICP real mode counters
  KVM: PPC: Book3S HV: Move virtual mode ICP functions to real-mode
  KVM: PPC: Book3S HV: Convert ICS mutex lock to spin lock
  KVM: PPC: Book3S HV: Add guest->host real mode completion counters
  KVM: PPC: Book3S HV: Add helpers for lock/unlock hpte
  ...
2015-04-26 13:06:22 -07:00
Paul Mackerras
66feed61cd KVM: PPC: Book3S HV: Use msgsnd for signalling threads on POWER8
This uses msgsnd where possible for signalling other threads within
the same core on POWER8 systems, rather than IPIs through the XICS
interrupt controller.  This includes waking secondary threads to run
the guest, the interrupts generated by the virtual XICS, and the
interrupts to bring the other threads out of the guest when exiting.

Aggregated statistics from debugfs across vcpus for a guest with 32
vcpus, 8 threads/vcore, running on a POWER8, show this before the
change:

 rm_entry:     3387.6ns (228 - 86600, 1008969 samples)
  rm_exit:     4561.5ns (12 - 3477452, 1009402 samples)
  rm_intr:     1660.0ns (12 - 553050, 3600051 samples)

and this after the change:

 rm_entry:     3060.1ns (212 - 65138, 953873 samples)
  rm_exit:     4244.1ns (12 - 9693408, 954331 samples)
  rm_intr:     1342.3ns (12 - 1104718, 3405326 samples)

for a test of booting Fedora 20 big-endian to the login prompt.

The time taken for a H_PROD hcall (which is handled in the host
kernel) went down from about 35 microseconds to about 16 microseconds
with this change.

The noinline added to kvmppc_run_core turned out to be necessary for
good performance, at least with gcc 4.9.2 as packaged with Fedora 21
and a little-endian POWER8 host.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:34 +02:00
Paul Mackerras
eddb60fb14 KVM: PPC: Book3S HV: Translate kvmhv_commence_exit to C
This replaces the assembler code for kvmhv_commence_exit() with C code
in book3s_hv_builtin.c.  It also moves the IPI sending code that was
in book3s_hv_rm_xics.c into a new kvmhv_rm_send_ipi() function so it
can be used by kvmhv_commence_exit() as well as icp_rm_set_vcpu_irq().

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:34 +02:00
Paul Mackerras
6af27c847a KVM: PPC: Book3S HV: Streamline guest entry and exit
On entry to the guest, secondary threads now wait for the primary to
switch the MMU after loading up most of their state, rather than before.
This means that the secondary threads get into the guest sooner, in the
common case where the secondary threads get to kvmppc_hv_entry before
the primary thread.

On exit, the first thread out increments the exit count and interrupts
the other threads (to get them out of the guest) before saving most
of its state, rather than after.  That means that the other threads
exit sooner and means that the first thread doesn't spend so much
time waiting for the other threads at the point where the MMU gets
switched back to the host.

This pulls out the code that increments the exit count and interrupts
other threads into a separate function, kvmhv_commence_exit().
This also makes sure that r12 and vcpu->arch.trap are set correctly
in some corner cases.

Statistics from /sys/kernel/debug/kvm/vm*/vcpu*/timings show the
improvement.  Aggregating across vcpus for a guest with 32 vcpus,
8 threads/vcore, running on a POWER8, gives this before the change:

 rm_entry:     avg 4537.3ns (222 - 48444, 1068878 samples)
  rm_exit:     avg 4787.6ns (152 - 165490, 1010717 samples)
  rm_intr:     avg 1673.6ns (12 - 341304, 3818691 samples)

and this after the change:

 rm_entry:     avg 3427.7ns (232 - 68150, 1118921 samples)
  rm_exit:     avg 4716.0ns (12 - 150720, 1119477 samples)
  rm_intr:     avg 1614.8ns (12 - 522436, 3850432 samples)

showing a substantial reduction in the time spent per guest entry in
the real-mode guest entry code, and smaller reductions in the real
mode guest exit and interrupt handling times.  (The test was to start
the guest and boot Fedora 20 big-endian to the login prompt.)

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:33 +02:00
Paul Mackerras
7d6c40da19 KVM: PPC: Book3S HV: Use bitmap of active threads rather than count
Currently, the entry_exit_count field in the kvmppc_vcore struct
contains two 8-bit counts, one of the threads that have started entering
the guest, and one of the threads that have started exiting the guest.
This changes it to an entry_exit_map field which contains two bitmaps
of 8 bits each.  The advantage of doing this is that it gives us a
bitmap of which threads need to be signalled when exiting the guest.
That means that we no longer need to use the trick of setting the
HDEC to 0 to pull the other threads out of the guest, which led in
some cases to a spurious HDEC interrupt on the next guest entry.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:33 +02:00
Paul Mackerras
fd6d53b124 KVM: PPC: Book3S HV: Use decrementer to wake napping threads
This arranges for threads that are napping due to their vcpu having
ceded or due to not having a vcpu to wake up at the end of the guest's
timeslice without having to be poked with an IPI.  We do that by
arranging for the decrementer to contain a value no greater than the
number of timebase ticks remaining until the end of the timeslice.
In the case of a thread with no vcpu, this number is in the hypervisor
decrementer already.  In the case of a ceded vcpu, we use the smaller
of the HDEC value and the DEC value.

Using the DEC like this when ceded means we need to save and restore
the guest decrementer value around the nap.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:33 +02:00
Paul Mackerras
ccc07772c9 KVM: PPC: Book3S HV: Don't wake thread with no vcpu on guest IPI
When running a multi-threaded guest and vcpu 0 in a virtual core
is not running in the guest (i.e. it is busy elsewhere in the host),
thread 0 of the physical core will switch the MMU to the guest and
then go to nap mode in the code at kvm_do_nap.  If the guest sends
an IPI to thread 0 using the msgsndp instruction, that will wake
up thread 0 and cause all the threads in the guest to exit to the
host unnecessarily.  To avoid the unnecessary exit, this arranges
for the PECEDP bit to be cleared in this situation.  When napping
due to a H_CEDE from the guest, we still set PECEDP so that the
thread will wake up on an IPI sent using msgsndp.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:32 +02:00
Paul Mackerras
5d5b99cd68 KVM: PPC: Book3S HV: Get rid of vcore nap_count and n_woken
We can tell when a secondary thread has finished running a guest by
the fact that it clears its kvm_hstate.kvm_vcpu pointer, so there
is no real need for the nap_count field in the kvmppc_vcore struct.
This changes kvmppc_wait_for_nap to poll the kvm_hstate.kvm_vcpu
pointers of the secondary threads rather than polling vc->nap_count.
Besides reducing the size of the kvmppc_vcore struct by 8 bytes,
this also means that we can tell which secondary threads have got
stuck and thus print a more informative error message.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:32 +02:00
Paul Mackerras
25fedfca94 KVM: PPC: Book3S HV: Move vcore preemption point up into kvmppc_run_vcpu
Rather than calling cond_resched() in kvmppc_run_core() before doing
the post-processing for the vcpus that we have just run (that is,
calling kvmppc_handle_exit_hv(), kvmppc_set_timer(), etc.), we now do
that post-processing before calling cond_resched(), and that post-
processing is moved out into its own function, post_guest_process().

The reschedule point is now in kvmppc_run_vcpu() and we define a new
vcore state, VCORE_PREEMPT, to indicate that that the vcore's runner
task is runnable but not running.  (Doing the reschedule with the
vcore in VCORE_INACTIVE state would be bad because there are potentially
other vcpus waiting for the runner in kvmppc_wait_for_exec() which
then wouldn't get woken up.)

Also, we make use of the handy cond_resched_lock() function, which
unlocks and relocks vc->lock for us around the reschedule.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:32 +02:00
Paul Mackerras
1f09c3ed86 KVM: PPC: Book3S HV: Minor cleanups
* Remove unused kvmppc_vcore::n_busy field.
* Remove setting of RMOR, since it was only used on PPC970 and the
  PPC970 KVM support has been removed.
* Don't use r1 or r2 in setting the runlatch since they are
  conventionally reserved for other things; use r0 instead.
* Streamline the code a little and remove the ext_interrupt_to_host
  label.
* Add some comments about register usage.
* hcall_try_real_mode doesn't need to be global, and can't be
  called from C code anyway.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:32 +02:00
Paul Mackerras
d911f0bedd KVM: PPC: Book3S HV: Simplify handling of VCPUs that need a VPA update
Previously, if kvmppc_run_core() was running a VCPU that needed a VPA
update (i.e. one of its 3 virtual processor areas needed to be pinned
in memory so the host real mode code can update it on guest entry and
exit), we would drop the vcore lock and do the update there and then.
Future changes will make it inconvenient to drop the lock, so instead
we now remove it from the list of runnable VCPUs and wake up its
VCPU task.  This will have the effect that the VCPU task will exit
kvmppc_run_vcpu(), go around the do loop in kvmppc_vcpu_run_hv(), and
re-enter kvmppc_run_vcpu(), whereupon it will do the necessary call
to kvmppc_update_vpas() and then rejoin the vcore.

The one complication is that the runner VCPU (whose VCPU task is the
current task) might be one of the ones that gets removed from the
runnable list.  In that case we just return from kvmppc_run_core()
and let the code in kvmppc_run_vcpu() wake up another VCPU task to be
the runner if necessary.

This all means that the VCORE_STARTING state is no longer used, so we
remove it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:31 +02:00
Paul Mackerras
b6c295df31 KVM: PPC: Book3S HV: Accumulate timing information for real-mode code
This reads the timebase at various points in the real-mode guest
entry/exit code and uses that to accumulate total, minimum and
maximum time spent in those parts of the code.  Currently these
times are accumulated per vcpu in 5 parts of the code:

* rm_entry - time taken from the start of kvmppc_hv_entry() until
  just before entering the guest.
* rm_intr - time from when we take a hypervisor interrupt in the
  guest until we either re-enter the guest or decide to exit to the
  host.  This includes time spent handling hcalls in real mode.
* rm_exit - time from when we decide to exit the guest until the
  return from kvmppc_hv_entry().
* guest - time spend in the guest
* cede - time spent napping in real mode due to an H_CEDE hcall
  while other threads in the same vcore are active.

These times are exposed in debugfs in a directory per vcpu that
contains a file called "timings".  This file contains one line for
each of the 5 timings above, with the name followed by a colon and
4 numbers, which are the count (number of times the code has been
executed), the total time, the minimum time, and the maximum time,
all in nanoseconds.

The overhead of the extra code amounts to about 30ns for an hcall that
is handled in real mode (e.g. H_SET_DABR), which is about 25%.  Since
production environments may not wish to incur this overhead, the new
code is conditional on a new config symbol,
CONFIG_KVM_BOOK3S_HV_EXIT_TIMING.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:31 +02:00
Paul Mackerras
e23a808b16 KVM: PPC: Book3S HV: Create debugfs file for each guest's HPT
This creates a debugfs directory for each HV guest (assuming debugfs
is enabled in the kernel config), and within that directory, a file
by which the contents of the guest's HPT (hashed page table) can be
read.  The directory is named vmnnnn, where nnnn is the PID of the
process that created the guest.  The file is named "htab".  This is
intended to help in debugging problems in the host's management
of guest memory.

The contents of the file consist of a series of lines like this:

  3f48 4000d032bf003505 0000000bd7ff1196 00000003b5c71196

The first field is the index of the entry in the HPT, the second and
third are the HPT entry, so the third entry contains the real page
number that is mapped by the entry if the entry's valid bit is set.
The fourth field is the guest's view of the second doubleword of the
entry, so it contains the guest physical address.  (The format of the
second through fourth fields are described in the Power ISA and also
in arch/powerpc/include/asm/mmu-hash64.h.)

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:31 +02:00
Suresh Warrier
6e0365b782 KVM: PPC: Book3S HV: Add ICP real mode counters
Add two counters to count how often we generate real-mode ICS resend
and reject events. The counters provide some performance statistics
that could be used in the future to consider if the real mode functions
need further optimizing. The counters are displayed as part of IPC and
ICP state provided by /sys/debug/kernel/powerpc/kvm* for each VM.

Also added two counters that count (approximately) how many times we
don't find an ICP or ICS we're looking for. These are not currently
exposed through sysfs, but can be useful when debugging crashes.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:30 +02:00
Suresh Warrier
b0221556db KVM: PPC: Book3S HV: Move virtual mode ICP functions to real-mode
Interrupt-based hypercalls return H_TOO_HARD to inform KVM that it needs
to switch to the host to complete the rest of hypercall function in
virtual mode. This patch ports the virtual mode ICS/ICP reject and resend
functions to be runnable in hypervisor real mode, thus avoiding the need
to switch to the host to execute these functions in virtual mode. However,
the hypercalls continue to return H_TOO_HARD for vcpu_wakeup and notify
events - these events cannot be done in real mode and they will still need
a switch to host virtual mode.

There are sufficient differences between the real mode code and the
virtual mode code for the ICS/ICP resend and reject functions that
for now the code has been duplicated instead of sharing common code.
In the future, we can look at creating common functions.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:30 +02:00
Suresh Warrier
34cb7954c0 KVM: PPC: Book3S HV: Convert ICS mutex lock to spin lock
Replaces the ICS mutex lock with a spin lock since we will be porting
these routines to real mode. Note that we need to disable interrupts
before we take the lock in anticipation of the fact that on the guest
side, we are running in the context of a hard irq and interrupts are
disabled (EE bit off) when the lock is acquired. Again, because we
will be acquiring the lock in hypervisor real mode, we need to use
an arch_spinlock_t instead of a normal spinlock here as we want to
avoid running any lockdep code (which may not be safe to execute in
real mode).

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:30 +02:00
Suresh E. Warrier
878610fe98 KVM: PPC: Book3S HV: Add guest->host real mode completion counters
Add counters to track number of times we switch from guest real mode
to host virtual mode during an interrupt-related hyper call because the
hypercall requires actions that cannot be completed in real mode. This
will help when making optimizations that reduce guest-host transitions.

It is safe to use an ordinary increment rather than an atomic operation
because there is one ICP per virtual CPU and kvmppc_xics_rm_complete()
only works on the ICP for the current VCPU.

The counters are displayed as part of IPC and ICP state provided by
/sys/debug/kernel/powerpc/kvm* for each VM.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:30 +02:00
Aneesh Kumar K.V
a4bd6eb07c KVM: PPC: Book3S HV: Add helpers for lock/unlock hpte
This adds helper routines for locking and unlocking HPTEs, and uses
them in the rest of the code.  We don't change any locking rules in
this patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:29 +02:00
Aneesh Kumar K.V
31037ecad2 KVM: PPC: Book3S HV: Remove RMA-related variables from code
We don't support real-mode areas now that 970 support is removed.
Remove the remaining details of rma from the code.  Also rename
rma_setup_done to hpte_setup_done to better reflect the changes.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:29 +02:00
Michael Ellerman
e928e9cb36 KVM: PPC: Book3S HV: Add fast real-mode H_RANDOM implementation.
Some PowerNV systems include a hardware random-number generator.
This HWRNG is present on POWER7+ and POWER8 chips and is capable of
generating one 64-bit random number every microsecond.  The random
numbers are produced by sampling a set of 64 unstable high-frequency
oscillators and are almost completely entropic.

PAPR defines an H_RANDOM hypercall which guests can use to obtain one
64-bit random sample from the HWRNG.  This adds a real-mode
implementation of the H_RANDOM hypercall.  This hypercall was
implemented in real mode because the latency of reading the HWRNG is
generally small compared to the latency of a guest exit and entry for
all the threads in the same virtual core.

Userspace can detect the presence of the HWRNG and the H_RANDOM
implementation by querying the KVM_CAP_PPC_HWRNG capability.  The
H_RANDOM hypercall implementation will only be invoked when the guest
does an H_RANDOM hypercall if userspace first enables the in-kernel
H_RANDOM implementation using the KVM_CAP_PPC_ENABLE_HCALL capability.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:29 +02:00
David Gibson
99342cf804 kvmppc: Implement H_LOGICAL_CI_{LOAD,STORE} in KVM
On POWER, storage caching is usually configured via the MMU - attributes
such as cache-inhibited are stored in the TLB and the hashed page table.

This makes correctly performing cache inhibited IO accesses awkward when
the MMU is turned off (real mode).  Some CPU models provide special
registers to control the cache attributes of real mode load and stores but
this is not at all consistent.  This is a problem in particular for SLOF,
the firmware used on KVM guests, which runs entirely in real mode, but
which needs to do IO to load the kernel.

To simplify this qemu implements two special hypercalls, H_LOGICAL_CI_LOAD
and H_LOGICAL_CI_STORE which simulate a cache-inhibited load or store to
a logical address (aka guest physical address).  SLOF uses these for IO.

However, because these are implemented within qemu, not the host kernel,
these bypass any IO devices emulated within KVM itself.  The simplest way
to see this problem is to attempt to boot a KVM guest from a virtio-blk
device with iothread / dataplane enabled.  The iothread code relies on an
in kernel implementation of the virtio queue notification, which is not
triggered by the IO hcalls, and so the guest will stall in SLOF unable to
load the guest OS.

This patch addresses this by providing in-kernel implementations of the
2 hypercalls, which correctly scan the KVM IO bus.  Any access to an
address not handled by the KVM IO bus will cause a VM exit, hitting the
qemu implementation as before.

Note that a userspace change is also required, in order to enable these
new hcall implementations with KVM_CAP_PPC_ENABLE_HCALL.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[agraf: fix compilation]
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21 15:21:28 +02:00
Shreyas B. Prabhu
a7e73e711e powerpc/kvm: Fix ppc64_defconfig + PPC_POWERNV=n build error
kvm_no_guest() calls power7_wakeup_loss() to put the thread into the
deepest supported idle state. power7_wakeup_loss() is defined in
arch/powerpc/kernel/idle_power7.S, which is compiled only when
PPC_P7_NAP=y.

And PPC_P7_NAP is selected when PPC_POWERNV=y.

Hence in cases where PPC_POWERNV=n and KVM_BOOK3S_64_HV=y we see the
following error:

  arch/powerpc/kvm/built-in.o: In function `kvm_no_guest':
  arch/powerpc/kvm/book3s_hv_rmhandlers.o:(.text+0x42c): undefined reference to `power7_wakeup_loss'

Fix this by adding PPC_POWERNV as a dependency for KVM_BOOK3S_64_HV.

Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-17 11:57:36 +10:00
Aneesh Kumar K.V
7d6e7f7ffa powerpc/mm/thp: Return pte address if we find trans_splitting.
For THP that is marked trans splitting, we return the pte.
This require the callers to handle the pmd_trans_splitting scenario,
if they care. All the current callers are either looking at pfn or
write_ok, hence we don't need to update them.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-17 11:23:40 +10:00
Aneesh Kumar K.V
691e95fd73 powerpc/mm/thp: Make page table walk safe against thp split/collapse
We can disable a THP split or a hugepage collapse by disabling irq.
We do send IPI to all the cpus in the early part of split/collapse,
and disabling local irq ensure we don't make progress with
split/collapse. If the THP is getting split we return NULL from
find_linux_pte_or_hugepte(). For all the current callers it should be ok.
We need to be careful if we want to use returned pte_t pointer outside
the irq disabled region. W.r.t to THP split, the pfn remains the same,
but then a hugepage collapse will result in a pfn change. There are
few steps we can take to avoid a hugepage collapse.One way is to take page
reference inside the irq disable region. Other option is to take
mmap_sem so that a parallel collapse will not happen. We can also
disable collapse by taking pmd_lock. Another method used by kvm
subsystem is to check whether we had a mmu_notifer update in between
using mmu_notifier_retry().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-17 11:23:39 +10:00
Aneesh Kumar K.V
dac5657067 KVM: PPC: Remove page table walk helpers
This patch remove helpers which we had used only once in the code.
Limiting page table walk variants help in ensuring that we won't
end up with code walking page table with wrong assumptions.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-17 11:23:24 +10:00
Aneesh Kumar K.V
5e1d44aef1 KVM: PPC: Use READ_ONCE when dereferencing pte_t pointer
pte can get updated from other CPUs as part of multiple activities
like THP split, huge page collapse, unmap. We need to make sure we
don't reload the pte value again and again for different checks.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-17 11:23:24 +10:00
Linus Torvalds
d19d5efd8c powerpc updates for 4.1
- Numerous minor fixes, cleanups etc.
 - More EEH work from Gavin to remove its dependency on device_nodes.
 - Memory hotplug implemented entirely in the kernel from Nathan Fontenot.
 - Removal of redundant CONFIG_PPC_OF by Kevin Hao.
 - Rewrite of VPHN parsing logic & tests from Greg Kurz.
 - A fix from Nish Aravamudan to reduce memory usage by clamping
   nodes_possible_map.
 - Support for pstore on powernv from Hari Bathini.
 - Removal of old powerpc specific byte swap routines by David Gibson.
 - Fix from Vasant Hegde to prevent the flash driver telling you it was flashing
   your firmware when it wasn't.
 - Patch from Ben Herrenschmidt to add an OPAL heartbeat driver.
 - Fix for an oops causing get/put_cpu_var() imbalance in perf by Jan Stancek.
 - Some fixes for migration from Tyrel Datwyler.
 - A new syscall to switch the cpu endian by Michael Ellerman.
 - Large series from Wei Yang to implement SRIOV, reviewed and acked by Bjorn.
 - A fix for the OPAL sensor driver from Cédric Le Goater.
 - Fixes to get STRICT_MM_TYPECHECKS building again by Michael Ellerman.
 - Large series from Daniel Axtens to make our PCI hooks per PHB rather than per
   machine.
 - Small patch from Sam Bobroff to explicitly abort non-suspended transactions
   on syscalls, plus a test to exercise it.
 - Numerous reworks and fixes for the 24x7 PMU from Sukadev Bhattiprolu.
 - Small patch to enable the hard lockup detector from Anton Blanchard.
 - Fix from Dave Olson for missing L2 cache information on some CPUs.
 - Some fixes from Michael Ellerman to get Cell machines booting again.
 - Freescale updates from Scott: Highlights include BMan device tree nodes, an
   MSI erratum workaround, a couple minor performance improvements, config
   updates, and misc fixes/cleanup.
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Merge tag 'powerpc-4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:

 - Numerous minor fixes, cleanups etc.

 - More EEH work from Gavin to remove its dependency on device_nodes.

 - Memory hotplug implemented entirely in the kernel from Nathan
   Fontenot.

 - Removal of redundant CONFIG_PPC_OF by Kevin Hao.

 - Rewrite of VPHN parsing logic & tests from Greg Kurz.

 - A fix from Nish Aravamudan to reduce memory usage by clamping
   nodes_possible_map.

 - Support for pstore on powernv from Hari Bathini.

 - Removal of old powerpc specific byte swap routines by David Gibson.

 - Fix from Vasant Hegde to prevent the flash driver telling you it was
   flashing your firmware when it wasn't.

 - Patch from Ben Herrenschmidt to add an OPAL heartbeat driver.

 - Fix for an oops causing get/put_cpu_var() imbalance in perf by Jan
   Stancek.

 - Some fixes for migration from Tyrel Datwyler.

 - A new syscall to switch the cpu endian by Michael Ellerman.

 - Large series from Wei Yang to implement SRIOV, reviewed and acked by
   Bjorn.

 - A fix for the OPAL sensor driver from Cédric Le Goater.

 - Fixes to get STRICT_MM_TYPECHECKS building again by Michael Ellerman.

 - Large series from Daniel Axtens to make our PCI hooks per PHB rather
   than per machine.

 - Small patch from Sam Bobroff to explicitly abort non-suspended
   transactions on syscalls, plus a test to exercise it.

 - Numerous reworks and fixes for the 24x7 PMU from Sukadev Bhattiprolu.

 - Small patch to enable the hard lockup detector from Anton Blanchard.

 - Fix from Dave Olson for missing L2 cache information on some CPUs.

 - Some fixes from Michael Ellerman to get Cell machines booting again.

 - Freescale updates from Scott: Highlights include BMan device tree
   nodes, an MSI erratum workaround, a couple minor performance
   improvements, config updates, and misc fixes/cleanup.

* tag 'powerpc-4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (196 commits)
  powerpc/powermac: Fix build error seen with powermac smp builds
  powerpc/pseries: Fix compile of memory hotplug without CONFIG_MEMORY_HOTREMOVE
  powerpc: Remove PPC32 code from pseries specific find_and_init_phbs()
  powerpc/cell: Fix iommu breakage caused by controller_ops change
  powerpc/eeh: Fix crash in eeh_add_device_early() on Cell
  powerpc/perf: Cap 64bit userspace backtraces to PERF_MAX_STACK_DEPTH
  powerpc/perf/hv-24x7: Fail 24x7 initcall if create_events_from_catalog() fails
  powerpc/pseries: Correct memory hotplug locking
  powerpc: Fix missing L2 cache size in /sys/devices/system/cpu
  powerpc: Add ppc64 hard lockup detector support
  oprofile: Disable oprofile NMI timer on ppc64
  powerpc/perf/hv-24x7: Add missing put_cpu_var()
  powerpc/perf/hv-24x7: Break up single_24x7_request
  powerpc/perf/hv-24x7: Define update_event_count()
  powerpc/perf/hv-24x7: Whitespace cleanup
  powerpc/perf/hv-24x7: Define add_event_to_24x7_request()
  powerpc/perf/hv-24x7: Rename hv_24x7_event_update
  powerpc/perf/hv-24x7: Move debug prints to separate function
  powerpc/perf/hv-24x7: Drop event_24x7_request()
  powerpc/perf/hv-24x7: Use pr_devel() to log message
  ...

Conflicts:
	tools/testing/selftests/powerpc/Makefile
	tools/testing/selftests/powerpc/tm/Makefile
2015-04-16 13:53:32 -05:00
Linus Torvalds
9003601310 The most interesting bit here is irqfd/ioeventfd support for ARM and ARM64.
ARM/ARM64: fixes for live migration, irqfd and ioeventfd support (enabling
 vhost, too), page aging
 
 s390: interrupt handling rework, allowing to inject all local interrupts
 via new ioctl and to get/set the full local irq state for migration
 and introspection.  New ioctls to access memory by virtual address,
 and to get/set the guest storage keys.  SIMD support.
 
 MIPS: FPU and MIPS SIMD Architecture (MSA) support.  Includes some patches
 from Ralf Baechle's MIPS tree.
 
 x86: bugfixes (notably for pvclock, the others are small) and cleanups.
 Another small latency improvement for the TSC deadline timer.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.1

  The most interesting bit here is irqfd/ioeventfd support for ARM and
  ARM64.

  Summary:

  ARM/ARM64:
     fixes for live migration, irqfd and ioeventfd support (enabling
     vhost, too), page aging

  s390:
     interrupt handling rework, allowing to inject all local interrupts
     via new ioctl and to get/set the full local irq state for migration
     and introspection.  New ioctls to access memory by virtual address,
     and to get/set the guest storage keys.  SIMD support.

  MIPS:
     FPU and MIPS SIMD Architecture (MSA) support.  Includes some
     patches from Ralf Baechle's MIPS tree.

  x86:
     bugfixes (notably for pvclock, the others are small) and cleanups.
     Another small latency improvement for the TSC deadline timer"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits)
  KVM: use slowpath for cross page cached accesses
  kvm: mmu: lazy collapse small sptes into large sptes
  KVM: x86: Clear CR2 on VCPU reset
  KVM: x86: DR0-DR3 are not clear on reset
  KVM: x86: BSP in MSR_IA32_APICBASE is writable
  KVM: x86: simplify kvm_apic_map
  KVM: x86: avoid logical_map when it is invalid
  KVM: x86: fix mixed APIC mode broadcast
  KVM: x86: use MDA for interrupt matching
  kvm/ppc/mpic: drop unused IRQ_testbit
  KVM: nVMX: remove unnecessary double caching of MAXPHYADDR
  KVM: nVMX: checks for address bits beyond MAXPHYADDR on VM-entry
  KVM: x86: cache maxphyaddr CPUID leaf in struct kvm_vcpu
  KVM: vmx: pass error code with internal error #2
  x86: vdso: fix pvclock races with task migration
  KVM: remove kvm_read_hva and kvm_read_hva_atomic
  KVM: x86: optimize delivery of TSC deadline timer interrupt
  KVM: x86: extract blocking logic from __vcpu_run
  kvm: x86: fix x86 eflags fixed bit
  KVM: s390: migrate vcpu interrupt state
  ...
2015-04-13 09:47:01 -07:00
Arseny Solokha
1945606031 kvm/ppc/mpic: drop unused IRQ_testbit
Drop unused static procedure which doesn't have callers within its
translation unit. It had been already removed independently in QEMU[1]
from the OpenPIC implementation borrowed from the kernel.

[1] https://lists.gnu.org/archive/html/qemu-devel/2014-06/msg01812.html

Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Cc: Alexander Graf <agraf@suse.de>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1424768706-23150-3-git-send-email-asolokha@kb.kras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-08 10:46:58 +02:00
Michael Ellerman
b7f859dda9 Merge branch 'next-remove-ldst' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc into next 2015-04-07 13:25:14 +10:00
Andre Przywara
af669ac6dc KVM: move iodev.h from virt/kvm/ to include/kvm
iodev.h contains definitions for the kvm_io_bus framework. This is
needed both by the generic KVM code in virt/kvm as well as by
architecture specific code under arch/. Putting the header file in
virt/kvm and using local includes in the architecture part seems at
least dodgy to me, so let's move the file into include/kvm, so that a
more natural "#include <kvm/iodev.h>" can be used by all of the code.
This also solves a problem later when using struct kvm_io_device
in arm_vgic.h.
Fixing up the FSF address in the GPL header and a wrong include path
on the way.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:12 +00:00
Nikolay Nikolaev
e32edf4fd0 KVM: Redesign kvm_io_bus_ API to pass VCPU structure to the callbacks.
This is needed in e.g. ARM vGIC emulation, where the MMIO handling
depends on the VCPU that does the access.

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:11 +00:00
David Gibson
d078eed35d powerpc: Cleanup KVM emulated load/store endian handling
Sometimes the KVM code on powerpc needs to emulate load or store
instructions from the guest, which can include both normal and byte
reversed forms.

We currently (AFAICT) handle this correctly, but some variable names are
very misleading.  In particular we use "is_bigendian" in several places to
actually mean "is the IO the same endian as the host", but we now support
little-endian powerpc hosts.  This also ties into the misleadingly named
ld_le*() and st_le*() functions, which in fact always byteswap, even on
an LE host.

This patch cleans this up by renaming to more accurate "host_swabbed", and
uses the generic swab*() functions instead of the powerpc specific and
misleadingly named ld_le*() and st_le*() functions.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:33:51 +11:00
Paul Mackerras
2bf27601c7 KVM: PPC: Book3S HV: Fix instruction emulation
Commit 4a157d61b4 ("KVM: PPC: Book3S HV: Fix endianness of
instruction obtained from HEIR register") had the side effect that
we no longer reset vcpu->arch.last_inst to -1 on guest exit in
the cases where the instruction is not fetched from the guest.
This means that if instruction emulation turns out to be required
in those cases, the host will emulate the wrong instruction, since
vcpu->arch.last_inst will contain the last instruction that was
emulated.

This fixes it by making sure that vcpu->arch.last_inst is reset
to -1 in those cases.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-20 11:42:33 +01:00
Paul Mackerras
ecb6d6185b KVM: PPC: Book3S HV: Endian fix for accessing VPA yield count
The VPA (virtual processor area) is defined by PAPR and is therefore
big-endian, so we need a be32_to_cpu when reading it in
kvmppc_get_yield_count().  Without this, H_CONFER always fails on a
little-endian host, causing SMP guests to waste time spinning on
spinlocks.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-20 11:42:08 +01:00
Paul Mackerras
8f902b005e KVM: PPC: Book3S HV: Fix spinlock/mutex ordering issue in kvmppc_set_lpcr()
Currently, kvmppc_set_lpcr() has a spinlock around the whole function,
and inside that does mutex_lock(&kvm->lock).  It is not permitted to
take a mutex while holding a spinlock, because the mutex_lock might
call schedule().  In addition, this causes lockdep to warn about a
lock ordering issue:

======================================================
[ INFO: possible circular locking dependency detected ]
3.18.0-kvm-04645-gdfea862-dirty #131 Not tainted
-------------------------------------------------------
qemu-system-ppc/8179 is trying to acquire lock:
 (&kvm->lock){+.+.+.}, at: [<d00000000ecc1f54>] .kvmppc_set_lpcr+0xf4/0x1c0 [kvm_hv]

but task is already holding lock:
 (&(&vcore->lock)->rlock){+.+...}, at: [<d00000000ecc1ea0>] .kvmppc_set_lpcr+0x40/0x1c0 [kvm_hv]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&(&vcore->lock)->rlock){+.+...}:
       [<c000000000b3c120>] .mutex_lock_nested+0x80/0x570
       [<d00000000ecc7a14>] .kvmppc_vcpu_run_hv+0xc4/0xe40 [kvm_hv]
       [<d00000000eb9f5cc>] .kvmppc_vcpu_run+0x2c/0x40 [kvm]
       [<d00000000eb9cb24>] .kvm_arch_vcpu_ioctl_run+0x54/0x160 [kvm]
       [<d00000000eb94478>] .kvm_vcpu_ioctl+0x4a8/0x7b0 [kvm]
       [<c00000000026cbb4>] .do_vfs_ioctl+0x444/0x770
       [<c00000000026cfa4>] .SyS_ioctl+0xc4/0xe0
       [<c000000000009264>] syscall_exit+0x0/0x98

-> #0 (&kvm->lock){+.+.+.}:
       [<c0000000000ff28c>] .lock_acquire+0xcc/0x1a0
       [<c000000000b3c120>] .mutex_lock_nested+0x80/0x570
       [<d00000000ecc1f54>] .kvmppc_set_lpcr+0xf4/0x1c0 [kvm_hv]
       [<d00000000ecc510c>] .kvmppc_set_one_reg_hv+0x4dc/0x990 [kvm_hv]
       [<d00000000eb9f234>] .kvmppc_set_one_reg+0x44/0x330 [kvm]
       [<d00000000eb9c9dc>] .kvm_vcpu_ioctl_set_one_reg+0x5c/0x150 [kvm]
       [<d00000000eb9ced4>] .kvm_arch_vcpu_ioctl+0x214/0x2c0 [kvm]
       [<d00000000eb940b0>] .kvm_vcpu_ioctl+0xe0/0x7b0 [kvm]
       [<c00000000026cbb4>] .do_vfs_ioctl+0x444/0x770
       [<c00000000026cfa4>] .SyS_ioctl+0xc4/0xe0
       [<c000000000009264>] syscall_exit+0x0/0x98

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&vcore->lock)->rlock);
                               lock(&kvm->lock);
                               lock(&(&vcore->lock)->rlock);
  lock(&kvm->lock);

 *** DEADLOCK ***

2 locks held by qemu-system-ppc/8179:
 #0:  (&vcpu->mutex){+.+.+.}, at: [<d00000000eb93f18>] .vcpu_load+0x28/0x90 [kvm]
 #1:  (&(&vcore->lock)->rlock){+.+...}, at: [<d00000000ecc1ea0>] .kvmppc_set_lpcr+0x40/0x1c0 [kvm_hv]

stack backtrace:
CPU: 4 PID: 8179 Comm: qemu-system-ppc Not tainted 3.18.0-kvm-04645-gdfea862-dirty #131
Call Trace:
[c000001a66c0f310] [c000000000b486ac] .dump_stack+0x88/0xb4 (unreliable)
[c000001a66c0f390] [c0000000000f8bec] .print_circular_bug+0x27c/0x3d0
[c000001a66c0f440] [c0000000000fe9e8] .__lock_acquire+0x2028/0x2190
[c000001a66c0f5d0] [c0000000000ff28c] .lock_acquire+0xcc/0x1a0
[c000001a66c0f6a0] [c000000000b3c120] .mutex_lock_nested+0x80/0x570
[c000001a66c0f7c0] [d00000000ecc1f54] .kvmppc_set_lpcr+0xf4/0x1c0 [kvm_hv]
[c000001a66c0f860] [d00000000ecc510c] .kvmppc_set_one_reg_hv+0x4dc/0x990 [kvm_hv]
[c000001a66c0f8d0] [d00000000eb9f234] .kvmppc_set_one_reg+0x44/0x330 [kvm]
[c000001a66c0f960] [d00000000eb9c9dc] .kvm_vcpu_ioctl_set_one_reg+0x5c/0x150 [kvm]
[c000001a66c0f9f0] [d00000000eb9ced4] .kvm_arch_vcpu_ioctl+0x214/0x2c0 [kvm]
[c000001a66c0faf0] [d00000000eb940b0] .kvm_vcpu_ioctl+0xe0/0x7b0 [kvm]
[c000001a66c0fcb0] [c00000000026cbb4] .do_vfs_ioctl+0x444/0x770
[c000001a66c0fd90] [c00000000026cfa4] .SyS_ioctl+0xc4/0xe0
[c000001a66c0fe30] [c000000000009264] syscall_exit+0x0/0x98

This fixes it by moving the mutex_lock()/mutex_unlock() pair outside
the spin-locked region.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-20 11:41:14 +01:00
Mahesh Salgaonkar
45706bb53d powerpc/book3s: Fix flush_tlb cpu_spec hook to take a generic argument.
The flush_tlb hook in cpu_spec was introduced as a generic function hook
to invalidate TLBs. But the current implementation of flush_tlb hook
takes IS (invalidation selector) as an argument which is architecture
dependent. Hence, It is not right to have a generic routine where caller
has to pass non-generic argument.

This patch fixes this and makes flush_tlb hook as high level API.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-17 07:52:48 +11:00
Linus Torvalds
c833e17e27 Tighten rules for ACCESS_ONCE
This series tightens the rules for ACCESS_ONCE to only work
 on scalar types. It also contains the necessary fixups as
 indicated by build bots of linux-next.
 Now everything is in place to prevent new non-scalar users
 of ACCESS_ONCE and we can continue to convert code to
 READ_ONCE/WRITE_ONCE.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux

Pull ACCESS_ONCE() rule tightening from Christian Borntraeger:
 "Tighten rules for ACCESS_ONCE

  This series tightens the rules for ACCESS_ONCE to only work on scalar
  types.  It also contains the necessary fixups as indicated by build
  bots of linux-next.  Now everything is in place to prevent new
  non-scalar users of ACCESS_ONCE and we can continue to convert code to
  READ_ONCE/WRITE_ONCE"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux:
  kernel: Fix sparse warning for ACCESS_ONCE
  next: sh: Fix compile error
  kernel: tighten rules for ACCESS ONCE
  mm/gup: Replace ACCESS_ONCE with READ_ONCE
  x86/spinlock: Leftover conversion ACCESS_ONCE->READ_ONCE
  x86/xen/p2m: Replace ACCESS_ONCE with READ_ONCE
  ppc/hugetlbfs: Replace ACCESS_ONCE with READ_ONCE
  ppc/kvm: Replace ACCESS_ONCE with READ_ONCE
2015-02-14 10:54:28 -08:00
Linus Torvalds
b9085bcbf5 Fairly small update, but there are some interesting new features.
Common: Optional support for adding a small amount of polling on each HLT
 instruction executed in the guest (or equivalent for other architectures).
 This can improve latency up to 50% on some scenarios (e.g. O_DSYNC writes
 or TCP_RR netperf tests).  This also has to be enabled manually for now,
 but the plan is to auto-tune this in the future.
 
 ARM/ARM64: the highlights are support for GICv3 emulation and dirty page
 tracking
 
 s390: several optimizations and bugfixes.  Also a first: a feature
 exposed by KVM (UUID and long guest name in /proc/sysinfo) before
 it is available in IBM's hypervisor! :)
 
 MIPS: Bugfixes.
 
 x86: Support for PML (page modification logging, a new feature in
 Broadwell Xeons that speeds up dirty page tracking), nested virtualization
 improvements (nested APICv---a nice optimization), usual round of emulation
 fixes.  There is also a new option to reduce latency of the TSC deadline
 timer in the guest; this needs to be tuned manually.
 
 Some commits are common between this pull and Catalin's; I see you
 have already included his tree.
 
 ARM has other conflicts where functions are added in the same place
 by 3.19-rc and 3.20 patches.  These are not large though, and entirely
 within KVM.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM update from Paolo Bonzini:
 "Fairly small update, but there are some interesting new features.

  Common:
     Optional support for adding a small amount of polling on each HLT
     instruction executed in the guest (or equivalent for other
     architectures).  This can improve latency up to 50% on some
     scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests).  This
     also has to be enabled manually for now, but the plan is to
     auto-tune this in the future.

  ARM/ARM64:
     The highlights are support for GICv3 emulation and dirty page
     tracking

  s390:
     Several optimizations and bugfixes.  Also a first: a feature
     exposed by KVM (UUID and long guest name in /proc/sysinfo) before
     it is available in IBM's hypervisor! :)

  MIPS:
     Bugfixes.

  x86:
     Support for PML (page modification logging, a new feature in
     Broadwell Xeons that speeds up dirty page tracking), nested
     virtualization improvements (nested APICv---a nice optimization),
     usual round of emulation fixes.

     There is also a new option to reduce latency of the TSC deadline
     timer in the guest; this needs to be tuned manually.

     Some commits are common between this pull and Catalin's; I see you
     have already included his tree.

  Powerpc:
     Nothing yet.

     The KVM/PPC changes will come in through the PPC maintainers,
     because I haven't received them yet and I might end up being
     offline for some part of next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits)
  KVM: ia64: drop kvm.h from installed user headers
  KVM: x86: fix build with !CONFIG_SMP
  KVM: x86: emulate: correct page fault error code for NoWrite instructions
  KVM: Disable compat ioctl for s390
  KVM: s390: add cpu model support
  KVM: s390: use facilities and cpu_id per KVM
  KVM: s390/CPACF: Choose crypto control block format
  s390/kernel: Update /proc/sysinfo file with Extended Name and UUID
  KVM: s390: reenable LPP facility
  KVM: s390: floating irqs: fix user triggerable endless loop
  kvm: add halt_poll_ns module parameter
  kvm: remove KVM_MMIO_SIZE
  KVM: MIPS: Don't leak FPU/DSP to guest
  KVM: MIPS: Disable HTW while in guest
  KVM: nVMX: Enable nested posted interrupt processing
  KVM: nVMX: Enable nested virtual interrupt delivery
  KVM: nVMX: Enable nested apic register virtualization
  KVM: nVMX: Make nested control MSRs per-cpu
  KVM: nVMX: Enable nested virtualize x2apic mode
  KVM: nVMX: Prepare for using hardware MSR bitmap
  ...
2015-02-13 09:55:09 -08:00
Mel Gorman
8a0516ed8b mm: convert p[te|md]_numa users to p[te|md]_protnone_numa
Convert existing users of pte_numa and friends to the new helper.  Note
that the kernel is broken after this patch is applied until the other page
table modifiers are also altered.  This patch layout is to make review
easier.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:08 -08:00
Linus Torvalds
d3f180ea1a powerpc updates for 3.20
Including:
 
 - Update of all defconfigs
 - Addition of a bunch of config options to modernise our defconfigs
 - Some PS3 updates from Geoff
 - Optimised memcmp for 64 bit from Anton
 - Fix for kprobes that allows 'perf probe' to work from Naveen
 - Several cxl updates from Ian & Ryan
 - Expanded support for the '24x7' PMU from Cody & Sukadev
 - Freescale updates from Scott:
   "Highlights include 8xx optimizations, some more work on datapath device
    tree content, e300 machine check support, t1040 corenet error reporting,
    and various cleanups and fixes."
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Merge tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:

 - Update of all defconfigs

 - Addition of a bunch of config options to modernise our defconfigs

 - Some PS3 updates from Geoff

 - Optimised memcmp for 64 bit from Anton

 - Fix for kprobes that allows 'perf probe' to work from Naveen

 - Several cxl updates from Ian & Ryan

 - Expanded support for the '24x7' PMU from Cody & Sukadev

 - Freescale updates from Scott:
    "Highlights include 8xx optimizations, some more work on datapath
     device tree content, e300 machine check support, t1040 corenet
     error reporting, and various cleanups and fixes"

* tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (102 commits)
  cxl: Add missing return statement after handling AFU errror
  cxl: Fail AFU initialisation if an invalid configuration record is found
  cxl: Export optional AFU configuration record in sysfs
  powerpc/mm: Warn on flushing tlb page in kernel context
  powerpc/powernv: Add OPAL soft-poweroff routine
  powerpc/perf/hv-24x7: Document sysfs event description entries
  powerpc/perf/hv-gpci: add the remaining gpci requests
  powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated
  powerpc/perf/hv-24x7: parse catalog and populate sysfs with events
  perf: define EVENT_DEFINE_RANGE_FORMAT_LITE helper
  perf: add PMU_EVENT_ATTR_STRING() helper
  perf: provide sysfs_show for struct perf_pmu_events_attr
  powerpc/kernel: Avoid initializing device-tree pointer twice
  powerpc: Remove old compile time disabled syscall tracing code
  powerpc/kernel: Make syscall_exit a local label
  cxl: Fix device_node reference counting
  powerpc/mm: bail out early when flushing TLB page
  powerpc: defconfigs: add MTD_SPI_NOR (new dependency for M25P80)
  perf/powerpc: reset event hw state when adding it to the PMU
  powerpc/qe: Use strlcpy()
  ...
2015-02-11 18:15:38 -08:00
Paolo Bonzini
f781951299 kvm: add halt_poll_ns module parameter
This patch introduces a new module parameter for the KVM module; when it
is present, KVM attempts a bit of polling on every HLT before scheduling
itself out via kvm_vcpu_block.

This parameter helps a lot for latency-bound workloads---in particular
I tested it with O_DSYNC writes with a battery-backed disk in the host.
In this case, writes are fast (because the data doesn't have to go all
the way to the platters) but they cannot be merged by either the host or
the guest.  KVM's performance here is usually around 30% of bare metal,
or 50% if you use cache=directsync or cache=writethrough (these
parameters avoid that the guest sends pointless flush requests, and
at the same time they are not slow because of the battery-backed cache).
The bad performance happens because on every halt the host CPU decides
to halt itself too.  When the interrupt comes, the vCPU thread is then
migrated to a new physical CPU, and in general the latency is horrible
because the vCPU thread has to be scheduled back in.

With this patch performance reaches 60-65% of bare metal and, more
important, 99% of what you get if you use idle=poll in the guest.  This
means that the tunable gets rid of this particular bottleneck, and more
work can be done to improve performance in the kernel or QEMU.

Of course there is some price to pay; every time an otherwise idle vCPUs
is interrupted by an interrupt, it will poll unnecessarily and thus
impose a little load on the host.  The above results were obtained with
a mostly random value of the parameter (500000), and the load was around
1.5-2.5% CPU usage on one of the host's core for each idle guest vCPU.

The patch also adds a new stat, /sys/kernel/debug/kvm/halt_successful_poll,
that can be used to tune the parameter.  It counts how many HLT
instructions received an interrupt during the polling period; each
successful poll avoids that Linux schedules the VCPU thread out and back
in, and may also avoid a likely trip to C1 and back for the physical CPU.

While the VM is idle, a Linux 4 VCPU VM halts around 10 times per second.
Of these halts, almost all are failed polls.  During the benchmark,
instead, basically all halts end within the polling period, except a more
or less constant stream of 50 per second coming from vCPUs that are not
running the benchmark.  The wasted time is thus very low.  Things may
be slightly different for Windows VMs, which have a ~10 ms timer tick.

The effect is also visible on Marcelo's recently-introduced latency
test for the TSC deadline timer.  Though of course a non-RT kernel has
awful latency bounds, the latency of the timer is around 8000-10000 clock
cycles compared to 20000-120000 without setting halt_poll_ns.  For the TSC
deadline timer, thus, the effect is both a smaller average latency and
a smaller variance.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-06 13:08:37 +01:00
Dominik Dingel
31928aa586 KVM: remove unneeded return value of vcpu_postcreate
The return value of kvm_arch_vcpu_postcreate is not checked in its
caller.  This is okay, because only x86 provides vcpu_postcreate right
now and it could only fail if vcpu_load failed.  But that is not
possible during KVM_CREATE_VCPU (kvm_arch_vcpu_load is void, too), so
just get rid of the unchecked return value.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:24:52 +01:00
Christian Borntraeger
5ee07612e9 ppc/kvm: Replace ACCESS_ONCE with READ_ONCE
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Change the ppc/kvm code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>
2015-01-19 14:14:07 +01:00
Pranith Kumar
83fe27ea53 rcu: Make SRCU optional by using CONFIG_SRCU
SRCU is not necessary to be compiled by default in all cases. For tinification
efforts not compiling SRCU unless necessary is desirable.

The current patch tries to make compiling SRCU optional by introducing a new
Kconfig option CONFIG_SRCU which is selected when any of the components making
use of SRCU are selected.

If we do not select CONFIG_SRCU, srcu.o will not be compiled at all.

   text    data     bss     dec     hex filename
   2007       0       0    2007     7d7 kernel/rcu/srcu.o

Size of arch/powerpc/boot/zImage changes from

   text    data     bss     dec     hex filename
 831552   64180   23944  919676   e087c arch/powerpc/boot/zImage : before
 829504   64180   23952  917636   e0084 arch/powerpc/boot/zImage : after

so the savings are about ~2000 bytes.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ]
2015-01-06 11:04:29 -08:00
Michael Ellerman
9a4fc4eaf1 powerpc/kvm: Create proper names for the kvm_host_state PMU fields
We have two arrays in kvm_host_state that contain register values for
the PMU. Currently we only create an asm-offsets symbol for the base of
the arrays, and do the array offset in the assembly code.

Creating an asm-offsets symbol for each field individually makes the
code much nicer to read, particularly for the MMCRx/SIxR/SDAR fields, and
might have helped us notice the recent double restore bug we had in this
code.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Alexander Graf <agraf@suse.de>
2014-12-29 15:45:55 +11:00
Linus Torvalds
66dcff86ba 3.19 changes for KVM:
- spring cleaning: removed support for IA64, and for hardware-assisted
 virtualization on the PPC970
 - ARM, PPC, s390 all had only small fixes
 
 For x86:
 - small performance improvements (though only on weird guests)
 - usual round of hardware-compliancy fixes from Nadav
 - APICv fixes
 - XSAVES support for hosts and guests.  XSAVES hosts were broken because
 the (non-KVM) XSAVES patches inadvertently changed the KVM userspace
 ABI whenever XSAVES was enabled; hence, this part is going to stable.
 Guest support is just a matter of exposing the feature and CPUID leaves
 support.
 
 Right now KVM is broken for PPC BookE in your tree (doesn't compile).
 I'll reply to the pull request with a patch, please apply it either
 before the pull request or in the merge commit, in order to preserve
 bisectability somewhat.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM update from Paolo Bonzini:
 "3.19 changes for KVM:

   - spring cleaning: removed support for IA64, and for hardware-
     assisted virtualization on the PPC970

   - ARM, PPC, s390 all had only small fixes

  For x86:
   - small performance improvements (though only on weird guests)
   - usual round of hardware-compliancy fixes from Nadav
   - APICv fixes
   - XSAVES support for hosts and guests.  XSAVES hosts were broken
     because the (non-KVM) XSAVES patches inadvertently changed the KVM
     userspace ABI whenever XSAVES was enabled; hence, this part is
     going to stable.  Guest support is just a matter of exposing the
     feature and CPUID leaves support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits)
  KVM: move APIC types to arch/x86/
  KVM: PPC: Book3S: Enable in-kernel XICS emulation by default
  KVM: PPC: Book3S HV: Improve H_CONFER implementation
  KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register
  KVM: PPC: Book3S HV: Remove code for PPC970 processors
  KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions
  KVM: PPC: Book3S HV: Simplify locking around stolen time calculations
  arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function
  arch: powerpc: kvm: book3s_pr.c: Remove unused function
  arch: powerpc: kvm: book3s.c: Remove some unused functions
  arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function
  KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked
  KVM: PPC: Book3S HV: ptes are big endian
  KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI
  KVM: PPC: Book3S HV: Fix KSM memory corruption
  KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI
  KVM: PPC: Book3S HV: Fix computation of tlbie operand
  KVM: PPC: Book3S HV: Add missing HPTE unlock
  KVM: PPC: BookE: Improve irq inject tracepoint
  arm/arm64: KVM: Require in-kernel vgic for the arch timers
  ...
2014-12-18 16:05:28 -08:00
Alexander Graf
91ed9e8a32 KVM: PPC: E500: Compile fix in this_cpu_write
Commit 69111bac42 ("powerpc: Replace __get_cpu_var uses") introduced
compile breakage to the e500 target by introducing invalid automatically
created C syntax.

Fix up the breakage and make the code compile again.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-18 16:02:26 -08:00
Anton Blanchard
476ce5ef09 KVM: PPC: Book3S: Enable in-kernel XICS emulation by default
The in-kernel XICS emulation is faster than doing it all in QEMU
and it has got a lot of testing, so enable it by default.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 22:23:22 +01:00
Sam Bobroff
90fd09f804 KVM: PPC: Book3S HV: Improve H_CONFER implementation
Currently the H_CONFER hcall is implemented in kernel virtual mode,
meaning that whenever a guest thread does an H_CONFER, all the threads
in that virtual core have to exit the guest.  This is bad for
performance because it interrupts the other threads even if they
are doing useful work.

The H_CONFER hcall is called by a guest VCPU when it is spinning on a
spinlock and it detects that the spinlock is held by a guest VCPU that
is currently not running on a physical CPU.  The idea is to give this
VCPU's time slice to the holder VCPU so that it can make progress
towards releasing the lock.

To avoid having the other threads exit the guest unnecessarily,
we add a real-mode implementation of H_CONFER that checks whether
the other threads are doing anything.  If all the other threads
are idle (i.e. in H_CEDE) or trying to confer (i.e. in H_CONFER),
it returns H_TOO_HARD which causes a guest exit and allows the
H_CONFER to be handled in virtual mode.

Otherwise it spins for a short time (up to 10 microseconds) to give
other threads the chance to observe that this thread is trying to
confer.  The spin loop also terminates when any thread exits the guest
or when all other threads are idle or trying to confer.  If the
timeout is reached, the H_CONFER returns H_SUCCESS.  In this case the
guest VCPU will recheck the spinlock word and most likely call
H_CONFER again.

This also improves the implementation of the H_CONFER virtual mode
handler.  If the VCPU is part of a virtual core (vcore) which is
runnable, there will be a 'runner' VCPU which has taken responsibility
for running the vcore.  In this case we yield to the runner VCPU
rather than the target VCPU.

We also introduce a check on the target VCPU's yield count: if it
differs from the yield count passed to H_CONFER, the target VCPU
has run since H_CONFER was called and may have already released
the lock.  This check is required by PAPR.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:53:39 +01:00
Paul Mackerras
4a157d61b4 KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register
There are two ways in which a guest instruction can be obtained from
the guest in the guest exit code in book3s_hv_rmhandlers.S.  If the
exit was caused by a Hypervisor Emulation interrupt (i.e. an illegal
instruction), the offending instruction is in the HEIR register
(Hypervisor Emulation Instruction Register).  If the exit was caused
by a load or store to an emulated MMIO device, we load the instruction
from the guest by turning data relocation on and loading the instruction
with an lwz instruction.

Unfortunately, in the case where the guest has opposite endianness to
the host, these two methods give results of different endianness, but
both get put into vcpu->arch.last_inst.  The HEIR value has been loaded
using guest endianness, whereas the lwz will load the instruction using
host endianness.  The rest of the code that uses vcpu->arch.last_inst
assumes it was loaded using host endianness.

To fix this, we define a new vcpu field to store the HEIR value.  Then,
in kvmppc_handle_exit_hv(), we transfer the value from this new field to
vcpu->arch.last_inst, doing a byte-swap if the guest and host endianness
differ.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:50:39 +01:00
Paul Mackerras
c17b98cf60 KVM: PPC: Book3S HV: Remove code for PPC970 processors
This removes the code that was added to enable HV KVM to work
on PPC970 processors.  The PPC970 is an old CPU that doesn't
support virtualizing guest memory.  Removing PPC970 support also
lets us remove the code for allocating and managing contiguous
real-mode areas, the code for the !kvm->arch.using_mmu_notifiers
case, the code for pinning pages of guest memory when first
accessed and keeping track of which pages have been pinned, and
the code for handling H_ENTER hypercalls in virtual mode.

Book3S HV KVM is now supported only on POWER7 and POWER8 processors.
The KVM_CAP_PPC_RMA capability now always returns 0.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:44:03 +01:00
Suresh E. Warrier
3c78f78af9 KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions
This patch adds trace points in the guest entry and exit code and also
for exceptions handled by the host in kernel mode - hypercalls and page
faults. The new events are added to /sys/kernel/debug/tracing/events
under a new subsystem called kvm_hv.

Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:29:27 +01:00
Paul Mackerras
2711e248a3 KVM: PPC: Book3S HV: Simplify locking around stolen time calculations
Currently the calculations of stolen time for PPC Book3S HV guests
uses fields in both the vcpu struct and the kvmppc_vcore struct.  The
fields in the kvmppc_vcore struct are protected by the
vcpu->arch.tbacct_lock of the vcpu that has taken responsibility for
running the virtual core.  This works correctly but confuses lockdep,
because it sees that the code takes the tbacct_lock for a vcpu in
kvmppc_remove_runnable() and then takes another vcpu's tbacct_lock in
vcore_stolen_time(), and it thinks there is a possibility of deadlock,
causing it to print reports like this:

=============================================
[ INFO: possible recursive locking detected ]
3.18.0-rc7-kvm-00016-g8db4bc6 #89 Not tainted
---------------------------------------------
qemu-system-ppc/6188 is trying to acquire lock:
 (&(&vcpu->arch.tbacct_lock)->rlock){......}, at: [<d00000000ecb1fe8>] .vcore_stolen_time+0x48/0xd0 [kvm_hv]

but task is already holding lock:
 (&(&vcpu->arch.tbacct_lock)->rlock){......}, at: [<d00000000ecb25a0>] .kvmppc_remove_runnable.part.3+0x30/0xd0 [kvm_hv]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&vcpu->arch.tbacct_lock)->rlock);
  lock(&(&vcpu->arch.tbacct_lock)->rlock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by qemu-system-ppc/6188:
 #0:  (&vcpu->mutex){+.+.+.}, at: [<d00000000eb93f98>] .vcpu_load+0x28/0xe0 [kvm]
 #1:  (&(&vcore->lock)->rlock){+.+...}, at: [<d00000000ecb41b0>] .kvmppc_vcpu_run_hv+0x530/0x1530 [kvm_hv]
 #2:  (&(&vcpu->arch.tbacct_lock)->rlock){......}, at: [<d00000000ecb25a0>] .kvmppc_remove_runnable.part.3+0x30/0xd0 [kvm_hv]

stack backtrace:
CPU: 40 PID: 6188 Comm: qemu-system-ppc Not tainted 3.18.0-rc7-kvm-00016-g8db4bc6 #89
Call Trace:
[c000000b2754f3f0] [c000000000b31b6c] .dump_stack+0x88/0xb4 (unreliable)
[c000000b2754f470] [c0000000000faeb8] .__lock_acquire+0x1878/0x2190
[c000000b2754f600] [c0000000000fbf0c] .lock_acquire+0xcc/0x1a0
[c000000b2754f6d0] [c000000000b2954c] ._raw_spin_lock_irq+0x4c/0x70
[c000000b2754f760] [d00000000ecb1fe8] .vcore_stolen_time+0x48/0xd0 [kvm_hv]
[c000000b2754f7f0] [d00000000ecb25b4] .kvmppc_remove_runnable.part.3+0x44/0xd0 [kvm_hv]
[c000000b2754f880] [d00000000ecb43ec] .kvmppc_vcpu_run_hv+0x76c/0x1530 [kvm_hv]
[c000000b2754f9f0] [d00000000eb9f46c] .kvmppc_vcpu_run+0x2c/0x40 [kvm]
[c000000b2754fa60] [d00000000eb9c9a4] .kvm_arch_vcpu_ioctl_run+0x54/0x160 [kvm]
[c000000b2754faf0] [d00000000eb94538] .kvm_vcpu_ioctl+0x498/0x760 [kvm]
[c000000b2754fcb0] [c000000000267eb4] .do_vfs_ioctl+0x444/0x770
[c000000b2754fd90] [c0000000002682a4] .SyS_ioctl+0xc4/0xe0
[c000000b2754fe30] [c0000000000092e4] syscall_exit+0x0/0x98

In order to make the locking easier to analyse, we change the code to
use a spinlock in the kvmppc_vcore struct to protect the stolen_tb and
preempt_tb fields.  This lock needs to be an irq-safe lock since it is
used in the kvmppc_core_vcpu_load_hv() and kvmppc_core_vcpu_put_hv()
functions, which are called with the scheduler rq lock held, which is
an irq-safe lock.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:20:09 +01:00
Rickard Strandqvist
a0499cf746 arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function
Remove the function inst_set_field() that is not used anywhere.

This was partially found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:13:29 +01:00
Rickard Strandqvist
6178839b01 arch: powerpc: kvm: book3s_pr.c: Remove unused function
Remove the function get_fpr_index() that is not used anywhere.

This was partially found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:13:16 +01:00
Rickard Strandqvist
54ca162a0c arch: powerpc: kvm: book3s.c: Remove some unused functions
Removes some functions that are not used anywhere:
kvmppc_core_load_guest_debugstate() kvmppc_core_load_host_debugstate()

This was partially found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:12:42 +01:00
Rickard Strandqvist
24aaaf22ea arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function
Remove the function sr_nx() that is not used anywhere.

This was partially found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17 13:12:25 +01:00
Suresh E. Warrier
1bc5d59c35 KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked
The kvmppc_vcore_blocked() code does not check for the wait condition
after putting the process on the wait queue. This means that it is
possible for an external interrupt to become pending, but the vcpu to
remain asleep until the next decrementer interrupt.  The fix is to
make one last check for pending exceptions and ceded state before
calling schedule().

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:25 +01:00
Cédric Le Goater
ffada016fb KVM: PPC: Book3S HV: ptes are big endian
When being restored from qemu, the kvm_get_htab_header are in native
endian, but the ptes are big endian.

This patch fixes restore on a KVM LE host. Qemu also needs a fix for
this :

     http://lists.nongnu.org/archive/html/qemu-ppc/2014-11/msg00008.html

Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:24 +01:00
Suresh E. Warrier
5b88cda665 KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI
This fixes some inaccuracies in the state machine for the virtualized
ICP when implementing the H_IPI hcall (Set_MFFR and related states):

1. The old code wipes out any pending interrupts when the new MFRR is
   more favored than the CPPR but less favored than a pending
   interrupt (by always modifying xisr and the pending_pri). This can
   cause us to lose a pending external interrupt.

   The correct code here is to only modify the pending_pri and xisr in
   the ICP if the MFRR is equal to or more favored than the current
   pending pri (since in this case, it is guaranteed that that there
   cannot be a pending external interrupt). The code changes are
   required in both kvmppc_rm_h_ipi and kvmppc_h_ipi.

2. Again, in both kvmppc_rm_h_ipi and kvmppc_h_ipi, there is a check
   for whether MFRR is being made less favored AND further if new MFFR
   is also less favored than the current CPPR, we check for any
   resends pending in the ICP. These checks look like they are
   designed to cover the case where if the MFRR is being made less
   favored, we opportunistically trigger a resend of any interrupts
   that had been previously rejected. Although, this is not a state
   described by PAPR, this is an action we actually need to do
   especially if the CPPR is already at 0xFF.  Because in this case,
   the resend bit will stay on until another ICP state change which
   may be a long time coming and the interrupt stays pending until
   then. The current code which checks for MFRR < CPPR is broken when
   CPPR is 0xFF since it will not get triggered in that case.

   Ideally, we would want to do a resend only if

   	prio(pending_interrupt) < mfrr && prio(pending_interrupt) < cppr

   where pending interrupt is the one that was rejected. But we don't
   have the priority of the pending interrupt state saved, so we
   simply trigger a resend whenever the MFRR is made less favored.

3. In kvmppc_rm_h_ipi, where we save state to pass resends to the
   virtual mode, we also need to save the ICP whose need_resend we
   reset since this does not need to be my ICP (vcpu->arch.icp) as is
   incorrectly assumed by the current code. A new field rm_resend_icp
   is added to the kvmppc_icp structure for this purpose.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:24 +01:00
Paul Mackerras
b4a839009a KVM: PPC: Book3S HV: Fix KSM memory corruption
Testing with KSM active in the host showed occasional corruption of
guest memory.  Typically a page that should have contained zeroes
would contain values that look like the contents of a user process
stack (values such as 0x0000_3fff_xxxx_xxx).

Code inspection in kvmppc_h_protect revealed that there was a race
condition with the possibility of granting write access to a page
which is read-only in the host page tables.  The code attempts to keep
the host mapping read-only if the host userspace PTE is read-only, but
if that PTE had been temporarily made invalid for any reason, the
read-only check would not trigger and the host HPTE could end up
read-write.  Examination of the guest HPT in the failure situation
revealed that there were indeed shared pages which should have been
read-only that were mapped read-write.

To close this race, we don't let a page go from being read-only to
being read-write, as far as the real HPTE mapping the page is
concerned (the guest view can go to read-write, but the actual mapping
stays read-only).  When the guest tries to write to the page, we take
an HDSI and let kvmppc_book3s_hv_page_fault take care of providing a
writable HPTE for the page.

This eliminates the occasional corruption of shared pages
that was previously seen with KSM active.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:24 +01:00
Mahesh Salgaonkar
dee6f24c33 KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI
When we get an HMI (hypervisor maintenance interrupt) while in a
guest, we see that guest enters into paused state.  The reason is, in
kvmppc_handle_exit_hv it falls through default path and returns to
host instead of resuming guest.  This causes guest to enter into
paused state.  HMI is a hypervisor only interrupt and it is safe to
resume the guest since the host has handled it already.  This patch
adds a switch case to resume the guest.

Without this patch we see guest entering into paused state with following
console messages:

[ 3003.329351] Severe Hypervisor Maintenance interrupt [Recovered]
[ 3003.329356]  Error detail: Timer facility experienced an error
[ 3003.329359] 	HMER: 0840000000000000
[ 3003.329360] 	TFMR: 4a12000980a84000
[ 3003.329366] vcpu c0000007c35094c0 (40):
[ 3003.329368] pc  = c0000000000c2ba0  msr = 8000000000009032  trap = e60
[ 3003.329370] r 0 = c00000000021ddc0  r16 = 0000000000000046
[ 3003.329372] r 1 = c00000007a02bbd0  r17 = 00003ffff27d5d98
[ 3003.329375] r 2 = c0000000010980b8  r18 = 00001fffffc9a0b0
[ 3003.329377] r 3 = c00000000142d6b8  r19 = c00000000142d6b8
[ 3003.329379] r 4 = 0000000000000002  r20 = 0000000000000000
[ 3003.329381] r 5 = c00000000524a110  r21 = 0000000000000000
[ 3003.329383] r 6 = 0000000000000001  r22 = 0000000000000000
[ 3003.329386] r 7 = 0000000000000000  r23 = c00000000524a110
[ 3003.329388] r 8 = 0000000000000000  r24 = 0000000000000001
[ 3003.329391] r 9 = 0000000000000001  r25 = c00000007c31da38
[ 3003.329393] r10 = c0000000014280b8  r26 = 0000000000000002
[ 3003.329395] r11 = 746f6f6c2f68656c  r27 = c00000000524a110
[ 3003.329397] r12 = 0000000028004484  r28 = c00000007c31da38
[ 3003.329399] r13 = c00000000fe01400  r29 = 0000000000000002
[ 3003.329401] r14 = 0000000000000046  r30 = c000000003011e00
[ 3003.329403] r15 = ffffffffffffffba  r31 = 0000000000000002
[ 3003.329404] ctr = c00000000041a670  lr  = c000000000272520
[ 3003.329405] srr0 = c00000000007e8d8 srr1 = 9000000000001002
[ 3003.329406] sprg0 = 0000000000000000 sprg1 = c00000000fe01400
[ 3003.329407] sprg2 = c00000000fe01400 sprg3 = 0000000000000005
[ 3003.329408] cr = 48004482  xer = 2000000000000000  dsisr = 42000000
[ 3003.329409] dar = 0000010015020048
[ 3003.329410] fault dar = 0000010015020048 dsisr = 42000000
[ 3003.329411] SLB (8 entries):
[ 3003.329412]   ESID = c000000008000000 VSID = 40016e7779000510
[ 3003.329413]   ESID = d000000008000001 VSID = 400142add1000510
[ 3003.329414]   ESID = f000000008000004 VSID = 4000eb1a81000510
[ 3003.329415]   ESID = 00001f000800000b VSID = 40004fda0a000d90
[ 3003.329416]   ESID = 00003f000800000c VSID = 400039f536000d90
[ 3003.329417]   ESID = 000000001800000d VSID = 0001251b35150d90
[ 3003.329417]   ESID = 000001000800000e VSID = 4001e46090000d90
[ 3003.329418]   ESID = d000080008000019 VSID = 40013d349c000400
[ 3003.329419] lpcr = c048800001847001 sdr1 = 0000001b19000006 last_inst = ffffffff
[ 3003.329421] trap=0xe60 | pc=0xc0000000000c2ba0 | msr=0x8000000000009032
[ 3003.329524] Severe Hypervisor Maintenance interrupt [Recovered]
[ 3003.329526]  Error detail: Timer facility experienced an error
[ 3003.329527] 	HMER: 0840000000000000
[ 3003.329527] 	TFMR: 4a12000980a94000
[ 3006.359786] Severe Hypervisor Maintenance interrupt [Recovered]
[ 3006.359792]  Error detail: Timer facility experienced an error
[ 3006.359795] 	HMER: 0840000000000000
[ 3006.359797] 	TFMR: 4a12000980a84000

 Id    Name                           State
----------------------------------------------------
 2     guest2                         running
 3     guest3                         paused
 4     guest4                         running

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:24 +01:00
Aneesh Kumar K.V
f6fb9e848c KVM: PPC: Book3S HV: Add missing HPTE unlock
In kvm_test_clear_dirty(), if we find an invalid HPTE we move on to the
next HPTE without unlocking the invalid one.  In fact we should never
find an invalid and unlocked HPTE in the rmap chain, but for robustness
we should unlock it.  This adds the missing unlock.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:23 +01:00
Alexander Graf
b6b612571e KVM: PPC: BookE: Improve irq inject tracepoint
When injecting an IRQ, we only document which IRQ priority (which translates
to IRQ type) gets injected. However, when reading traces you don't necessarily
have all the numbers in your head to know which IRQ really is meant.

This patch converts the IRQ number field to a symbolic name that is in sync
with the respective define. That way it's a lot easier for readers to figure
out what interrupt gets injected.

Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-15 13:27:23 +01:00
Linus Torvalds
a7cb7bb664 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree update from Jiri Kosina:
 "Usual stuff: documentation updates, printk() fixes, etc"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits)
  intel_ips: fix a type in error message
  cpufreq: cpufreq-dt: Move newline to end of error message
  ps3rom: fix error return code
  treewide: fix typo in printk and Kconfig
  ARM: dts: bcm63138: change "interupts" to "interrupts"
  Replace mentions of "list_struct" to "list_head"
  kernel: trace: fix printk message
  scsi: mpt2sas: fix ioctl in comment
  zbud, zswap: change module author email
  clocksource: Fix 'clcoksource' typo in comment
  arm: fix wording of "Crotex" in CONFIG_ARCH_EXYNOS3 help
  gpio: msm-v1: make boolean argument more obvious
  usb: Fix typo in usb-serial-simple.c
  PCI: Fix comment typo 'COMFIG_PM_OPS'
  powerpc: Fix comment typo 'CONIFG_8xx'
  powerpc: Fix comment typos 'CONFiG_ALTIVEC'
  clk: st: Spelling s/stucture/structure/
  isci: Spelling s/stucture/structure/
  usb: gadget: zero: Spelling s/infrastucture/infrastructure/
  treewide: Fix company name in module descriptions
  ...
2014-12-12 10:08:06 -08:00
Paul Mackerras
56548fc0e8 powerpc/powernv: Return to cpu offline loop when finished in KVM guest
When a secondary hardware thread has finished running a KVM guest, we
currently put that thread into nap mode using a nap instruction in
the KVM code.  This changes the code so that instead of doing a nap
instruction directly, we instead cause the call to power7_nap() that
put the thread into nap mode to return.  The reason for doing this is
to avoid having the KVM code having to know what low-power mode to
put the thread into.

In the case of a secondary thread used to run a KVM guest, the thread
will be offline from the point of view of the host kernel, and the
relevant power7_nap() call is the one in pnv_smp_cpu_disable().
In this case we don't want to clear pending IPIs in the offline loop
in that function, since that might cause us to miss the wakeup for
the next time the thread needs to run a guest.  To tell whether or
not to clear the interrupt, we use the SRR1 value returned from
power7_nap(), and check if it indicates an external interrupt.  We
arrange that the return from power7_nap() when we have finished running
a guest returns 0, so pending interrupts don't get flushed in that
case.

Note that it is important a secondary thread that has finished
executing in the guest, or that didn't have a guest to run, should
not return to power7_nap's caller while the kvm_hstate.hwthread_req
flag in the PACA is non-zero, because the return from power7_nap
will reenable the MMU, and the MMU might still be in guest context.
In this situation we spin at low priority in real mode waiting for
hwthread_req to become zero.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-12-08 13:16:31 +11:00
Masanari Iida
6774def642 treewide: fix typo in printk and Kconfig
This patch fix spelling typo in printk and Kconfig within
various part of kernel sources.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-11-20 14:56:11 +01:00
Anton Blanchard
68cf0d642f powerpc: Remove superfluous bootmem includes
Lots of places included bootmem.h even when not using bootmem.

Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-10 09:59:26 +11:00
Anton Blanchard
14ed740957 powerpc: Remove some old bootmem related comments
Now bootmem is gone from powerpc we can remove comments mentioning it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-10 09:59:25 +11:00
Christoph Lameter
69111bac42 powerpc: Replace __get_cpu_var uses
This still has not been merged and now powerpc is the only arch that does
not have this change. Sorry about missing linuxppc-dev before.

V2->V2
  - Fix up to work against 3.18-rc1

__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.

The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e.  using a global
register that may be set to the per cpu base.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
[mpe: Fix build errors caused by set/or_softirq_pending(), and rework
      assignment in __set_breakpoint() to use memcpy().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-03 12:12:32 +11:00
Linus Torvalds
e4e65676f2 Fixes and features for 3.18.
Apart from the usual cleanups, here is the summary of new features:
 
 - s390 moves closer towards host large page support
 
 - PowerPC has improved support for debugging (both inside the guest and
   via gdbstub) and support for e6500 processors
 
 - ARM/ARM64 support read-only memory (which is necessary to put firmware
   in emulated NOR flash)
 
 - x86 has the usual emulator fixes and nested virtualization improvements
   (including improved Windows support on Intel and Jailhouse hypervisor
   support on AMD), adaptive PLE which helps overcommitting of huge guests.
   Also included are some patches that make KVM more friendly to memory
   hot-unplug, and fixes for rare caching bugs.
 
 Two patches have trivial mm/ parts that were acked by Rik and Andrew.
 
 Note: I will soon switch to a subkey for signing purposes.  To verify
 future signed pull requests from me, please update my key with
 "gpg --recv-keys 9B4D86F2".  You should see 3 new subkeys---the
 one for signing will be a 2048-bit RSA key, 4E6B09D7.
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 Version: GnuPG v2.0.22 (GNU/Linux)
 
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Fixes and features for 3.18.

  Apart from the usual cleanups, here is the summary of new features:

   - s390 moves closer towards host large page support

   - PowerPC has improved support for debugging (both inside the guest
     and via gdbstub) and support for e6500 processors

   - ARM/ARM64 support read-only memory (which is necessary to put
     firmware in emulated NOR flash)

   - x86 has the usual emulator fixes and nested virtualization
     improvements (including improved Windows support on Intel and
     Jailhouse hypervisor support on AMD), adaptive PLE which helps
     overcommitting of huge guests.  Also included are some patches that
     make KVM more friendly to memory hot-unplug, and fixes for rare
     caching bugs.

  Two patches have trivial mm/ parts that were acked by Rik and Andrew.

  Note: I will soon switch to a subkey for signing purposes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (157 commits)
  kvm: do not handle APIC access page if in-kernel irqchip is not in use
  KVM: s390: count vcpu wakeups in stat.halt_wakeup
  KVM: s390/facilities: allow TOD-CLOCK steering facility bit
  KVM: PPC: BOOK3S: HV: CMA: Reserve cma region only in hypervisor mode
  arm/arm64: KVM: Report correct FSC for unsupported fault types
  arm/arm64: KVM: Fix VTTBR_BADDR_MASK and pgd alloc
  kvm: Fix kvm_get_page_retry_io __gup retval check
  arm/arm64: KVM: Fix set_clear_sgi_pend_reg offset
  kvm: x86: Unpin and remove kvm_arch->apic_access_page
  kvm: vmx: Implement set_apic_access_page_addr
  kvm: x86: Add request bit to reload APIC access page address
  kvm: Add arch specific mmu notifier for page invalidation
  kvm: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make it non-static
  kvm: Fix page ageing bugs
  kvm/x86/mmu: Pass gfn and level to rmapp callback.
  x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only
  kvm: x86: use macros to compute bank MSRs
  KVM: x86: Remove debug assertion of non-PAE reserved bits
  kvm: don't take vcpu mutex for obviously invalid vcpu ioctls
  kvm: Faults which trigger IO release the mmap_sem
  ...
2014-10-08 05:27:39 -04:00
Aneesh Kumar K.V
cec26bc3c1 KVM: PPC: BOOK3S: HV: CMA: Reserve cma region only in hypervisor mode
We use cma reserved area for creating guest hash page table.
Don't do the reservation in non-hypervisor mode. This avoids unnecessary
CMA reservation when booting with limited memory configs like
fadump and kdump.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-29 15:36:33 +02:00
Paolo Bonzini
00c027db0c Patch queue for ppc - 2014-09-24
New awesome things in this release:
 
   - E500: e6500 core support
   - E500: guest and remote debug support
   - Book3S: remote sw breakpoint support
   - Book3S: HV: Minor bugfixes
 
 Alexander Graf (1):
       KVM: PPC: Pass enum to kvmppc_get_last_inst
 
 Bharat Bhushan (8):
       KVM: PPC: BOOKE: allow debug interrupt at "debug level"
       KVM: PPC: BOOKE : Emulate rfdi instruction
       KVM: PPC: BOOKE: Allow guest to change MSR_DE
       KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
       KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
       KVM: PPC: BOOKE: Add one reg interface for DBSR
       KVM: PPC: BOOKE: Add one_reg documentation of SPRG9 and DBSR
       KVM: PPC: BOOKE: Emulate debug registers and exception
 
 Madhavan Srinivasan (2):
       powerpc/kvm: support to handle sw breakpoint
       powerpc/kvm: common sw breakpoint instr across ppc
 
 Michael Neuling (1):
       KVM: PPC: Book3S HV: Add register name when loading toc
 
 Mihai Caraman (10):
       powerpc/booke: Restrict SPE exception handlers to e200/e500 cores
       powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers
       KVM: PPC: Book3E: Increase FPU laziness
       KVM: PPC: Book3e: Add AltiVec support
       KVM: PPC: Make ONE_REG powerpc generic
       KVM: PPC: Move ONE_REG AltiVec support to powerpc
       KVM: PPC: Remove the tasklet used by the hrtimer
       KVM: PPC: Remove shared defines for SPE and AltiVec interrupts
       KVM: PPC: e500mc: Add support for single threaded vcpus on e6500 core
       KVM: PPC: Book3E: Enable e6500 core
 
 Paul Mackerras (2):
       KVM: PPC: Book3S HV: Increase timeout for grabbing secondary threads
       KVM: PPC: Book3S HV: Only accept host PVR value for guest PVR
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Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-next

Patch queue for ppc - 2014-09-24

New awesome things in this release:

  - E500: e6500 core support
  - E500: guest and remote debug support
  - Book3S: remote sw breakpoint support
  - Book3S: HV: Minor bugfixes

Alexander Graf (1):
      KVM: PPC: Pass enum to kvmppc_get_last_inst

Bharat Bhushan (8):
      KVM: PPC: BOOKE: allow debug interrupt at "debug level"
      KVM: PPC: BOOKE : Emulate rfdi instruction
      KVM: PPC: BOOKE: Allow guest to change MSR_DE
      KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
      KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
      KVM: PPC: BOOKE: Add one reg interface for DBSR
      KVM: PPC: BOOKE: Add one_reg documentation of SPRG9 and DBSR
      KVM: PPC: BOOKE: Emulate debug registers and exception

Madhavan Srinivasan (2):
      powerpc/kvm: support to handle sw breakpoint
      powerpc/kvm: common sw breakpoint instr across ppc

Michael Neuling (1):
      KVM: PPC: Book3S HV: Add register name when loading toc

Mihai Caraman (10):
      powerpc/booke: Restrict SPE exception handlers to e200/e500 cores
      powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers
      KVM: PPC: Book3E: Increase FPU laziness
      KVM: PPC: Book3e: Add AltiVec support
      KVM: PPC: Make ONE_REG powerpc generic
      KVM: PPC: Move ONE_REG AltiVec support to powerpc
      KVM: PPC: Remove the tasklet used by the hrtimer
      KVM: PPC: Remove shared defines for SPE and AltiVec interrupts
      KVM: PPC: e500mc: Add support for single threaded vcpus on e6500 core
      KVM: PPC: Book3E: Enable e6500 core

Paul Mackerras (2):
      KVM: PPC: Book3S HV: Increase timeout for grabbing secondary threads
      KVM: PPC: Book3S HV: Only accept host PVR value for guest PVR
2014-09-24 23:19:45 +02:00
Andres Lagar-Cavilla
5712846808 kvm: Fix page ageing bugs
1. We were calling clear_flush_young_notify in unmap_one, but we are
within an mmu notifier invalidate range scope. The spte exists no more
(due to range_start) and the accessed bit info has already been
propagated (due to kvm_pfn_set_accessed). Simply call
clear_flush_young.

2. We clear_flush_young on a primary MMU PMD, but this may be mapped
as a collection of PTEs by the secondary MMU (e.g. during log-dirty).
This required expanding the interface of the clear_flush_young mmu
notifier, so a lot of code has been trivially touched.

3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate
the access bit by blowing the spte. This requires proper synchronizing
with MMU notifier consumers, like every other removal of spte's does.

Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:07:58 +02:00
Alexander Graf
8d0eff6385 KVM: PPC: Pass enum to kvmppc_get_last_inst
The kvmppc_get_last_inst function recently received a facelift that allowed
us to pass an enum of the type of instruction we want to read into it rather
than an unreadable boolean.

Unfortunately, not all callers ended up passing the enum. This wasn't really
an issue as "true" and "false" happen to match the two enum values we have,
but it's still hard to read.

Update all callers of kvmppc_get_last_inst() to follow the new calling
convention.

Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:36 +02:00
Madhavan Srinivasan
033aaa14af powerpc/kvm: common sw breakpoint instr across ppc
This patch extends the use of illegal instruction as software
breakpoint instruction across the ppc platform. Patch extends
booke program interrupt code to support software breakpoint.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[agraf: Fix bookehv]
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:36 +02:00
Madhavan Srinivasan
a59c1d9e60 powerpc/kvm: support to handle sw breakpoint
This patch adds kernel side support for software breakpoint.
Design is that, by using an illegal instruction, we trap to hypervisor
via Emulation Assistance interrupt, where we check for the illegal instruction
and accordingly we return to Host or Guest. Patch also adds support for
software breakpoint in PR KVM.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:35 +02:00
Mihai Caraman
d2ca32a2d4 KVM: PPC: Book3E: Enable e6500 core
Now that AltiVec and hardware thread support is in place enable e6500 core.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:35 +02:00
Mihai Caraman
188e267ce2 KVM: PPC: e500mc: Add support for single threaded vcpus on e6500 core
ePAPR represents hardware threads as cpu node properties in device tree.
So with existing QEMU, hardware threads are simply exposed as vcpus with
one hardware thread.

The e6500 core shares TLBs between hardware threads. Without tlb write
conditional instruction, the Linux kernel uses per core mechanisms to
protect against duplicate TLB entries.

The guest is unable to detect real siblings threads, so it can't use the
TLB protection mechanism. An alternative solution is to use the hypervisor
to allocate different lpids to guest's vcpus that runs simultaneous on real
siblings threads. On systems with two threads per core this patch halves
the size of the lpid pool that the allocator sees and use two lpids per VM.
Use even numbers to speedup vcpu lpid computation with consecutive lpids
per VM: vm1 will use lpids 2 and 3, vm2 lpids 4 and 5, and so on.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[agraf: fix spelling]
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:35 +02:00
Paul Mackerras
9333e6c4c1 KVM: PPC: Book3S HV: Only accept host PVR value for guest PVR
Since the guest can read the machine's PVR (Processor Version Register)
directly and see the real value, we should disallow userspace from
setting any value for the guest's PVR other than the real host value.
Therefore this makes kvm_arch_vcpu_set_sregs_hv() check the supplied
PVR value and return an error if it is different from the host value,
which has been put into vcpu->arch.pvr at vcpu creation time.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:34 +02:00
Paul Mackerras
b754c739ee KVM: PPC: Book3S HV: Increase timeout for grabbing secondary threads
Occasional failures have been seen with split-core mode and migration
where the message "KVM: couldn't grab cpu" appears.  This increases
the length of time that we wait from 1ms to 10ms, which seems to
work around the issue.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:34 +02:00
Mihai Caraman
d02d4d156e KVM: PPC: Remove the tasklet used by the hrtimer
Powerpc timer implementation is a copycat version of s390. Now that they removed
the tasklet with commit ea74c0ea1b follow this
optimization.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Bogdan Purcareata <bogdan.purcareata@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:34 +02:00
Bharat Bhushan
2f699a59f3 KVM: PPC: BOOKE: Emulate debug registers and exception
This patch emulates debug registers and debug exception
to support guest using debug resource. This enables running
gdb/kgdb etc in guest.

On BOOKE architecture we cannot share debug resources between QEMU and
guest because:
    When QEMU is using debug resources then debug exception must
    be always enabled. To achieve this we set MSR_DE and also set
    MSRP_DEP so guest cannot change MSR_DE.

    When emulating debug resource for guest we want guest
    to control MSR_DE (enable/disable debug interrupt on need).

    So above mentioned two configuration cannot be supported
    at the same time. So the result is that we cannot share
    debug resources between QEMU and Guest on BOOKE architecture.

In the current design QEMU gets priority over guest, this means that if
QEMU is using debug resources then guest cannot use them and if guest is
using debug resource then QEMU can overwrite them.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:33 +02:00
Mihai Caraman
3840edc803 KVM: PPC: Move ONE_REG AltiVec support to powerpc
Move ONE_REG AltiVec support to powerpc generic layer.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:33 +02:00
Mihai Caraman
8a41ea53b3 KVM: PPC: Make ONE_REG powerpc generic
Make ONE_REG generic for server and embedded architectures by moving
kvm_vcpu_ioctl_get_one_reg() and kvm_vcpu_ioctl_set_one_reg() functions
to powerpc layer.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:33 +02:00
Mihai Caraman
95d80a294b KVM: PPC: Book3e: Add AltiVec support
Add AltiVec support in KVM for Book3e. FPU support gracefully reuse host
infrastructure so follow the same approach for AltiVec.

Book3e specification defines shared interrupt numbers for SPE and AltiVec
units. Still SPE is present in e200/e500v2 cores while AltiVec is present in
e6500 core. So we can currently decide at compile-time which of the SPE or
AltiVec units to support exclusively by using CONFIG_SPE_POSSIBLE and
CONFIG_PPC_E500MC defines. As Alexander Graf suggested, keep SPE and AltiVec
exception handlers distinct to improve code readability.

Guests have the privilege to enable AltiVec, so we always need to support
AltiVec in KVM and implicitly in host to reflect interrupts and to save/restore
the unit context. KVM will be loaded on cores with AltiVec unit only if
CONFIG_ALTIVEC is defined. Use this define to guard KVM AltiVec logic.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:32 +02:00
Mihai Caraman
3efc7da61f KVM: PPC: Book3E: Increase FPU laziness
Increase FPU laziness by loading the guest state into the unit before entering
the guest instead of doing it on each vcpu schedule. Without this improvement
an interrupt may claim floating point corrupting guest state.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:32 +02:00
Michael Neuling
06a29e4274 KVM: PPC: Book3S HV: Add register name when loading toc
Add 'r' to register name r2 in kvmppc_hv_enter.

Also update comment at the top of kvmppc_hv_enter to indicate that R2/TOC is
non-volatile.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:31 +02:00
Bharat Bhushan
2c5096720f KVM: PPC: BOOKE: Add one reg interface for DBSR
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:30 +02:00
Bharat Bhushan
348ba71081 KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
Guest visible debug register and hardware visible debug registers are
same, so ther is no need to have arch->shadow_dbg_reg, instead use
arch->dbg_reg.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:30 +02:00
Bharat Bhushan
2190991e7c KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
Dbsr is not visible to userspace and we do not think any need to
expose this to userspace because:
  Userspace cannot inject debug interrupt to guest (as this
  does not know guest ability to handle debug interrupt), so
  userspace will always clear DBSR.
  Now if userspace has to always clear DBSR in KVM_EXIT_DEBUG
  handling then clearing dbsr in kernel looks simple as this
  avoid doing SET_SREGS/set_one_reg() to clear DBSR

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:30 +02:00
Bharat Bhushan
37277b1129 KVM: PPC: BOOKE: Allow guest to change MSR_DE
This patch changes the default behavior of MSRP_DEP, that is
guest is not allowed to change the MSR_DE, to guest can change
MSR_DE. When userspace is debugging guest then it override the
default behavior and set MSRP_DEP. This stops guest to change
MSR_DE when userspace is debugging guest.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:29 +02:00
Bharat Bhushan
c8ca97ca9b KVM: PPC: BOOKE : Emulate rfdi instruction
This patch adds "rfdi" instruction emulation which is required for
guest debug hander on BOOKE-HV

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:29 +02:00
Bharat Bhushan
9fee7563cd KVM: PPC: BOOKE: allow debug interrupt at "debug level"
Debug interrupt can be either "critical level" or "debug level".
There are separate set of save/restore registers used for different level.
Example: DSRR0/DSRR1 are used for "debug level" and CSRR0/CSRR1
are used for critical level debug interrupt.

Using CPU_FTR_DEBUG_LVL_EXC to decide which interrupt level to be used.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:29 +02:00
Laurent Dufour
02a68d0503 powerpc/kvm/cma: Fix panic introduces by signed shift operation
fc95ca7284 introduces a memset in
kvmppc_alloc_hpt since the general CMA doesn't clear the memory it
allocates.

However, the size argument passed to memset is computed from a signed value
and its signed bit is extended by the cast the compiler is doing. This lead
to extremely large size value when dealing with order value >= 31, and
almost all the memory following the allocated space is cleaned. As a
consequence, the system is panicing and may even fail spawning the kdump
kernel.

This fix makes use of an unsigned value for the memset's size argument to
avoid sign extension. Among this fix, another shift operation which may
lead to signed extended value too is also fixed.

Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-03 10:34:07 +02:00
Radim Krčmář
13a34e067e KVM: remove garbage arg to *hardware_{en,dis}able
In the beggining was on_each_cpu(), which required an unused argument to
kvm_arch_ops.hardware_{en,dis}able, but this was soon forgotten.

Remove unnecessary arguments that stem from this.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-29 16:35:55 +02:00
Radim Krčmář
0865e636ae KVM: static inline empty kvm_arch functions
Using static inline is going to save few bytes and cycles.
For example on powerpc, the difference is 700 B after stripping.
(5 kB before)

This patch also deals with two overlooked empty functions:
kvm_arch_flush_shadow was not removed from arch/mips/kvm/mips.c
  2df72e9bc KVM: split kvm_arch_flush_shadow
and kvm_arch_sched_in never made it into arch/ia64/kvm/kvm-ia64.c.
  e790d9ef6 KVM: add kvm_arch_sched_in

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-29 16:35:55 +02:00
Radim Krčmář
e790d9ef64 KVM: add kvm_arch_sched_in
Introduce preempt notifiers for architecture specific code.
Advantage over creating a new notifier in every arch is slightly simpler
code and guaranteed call order with respect to kvm_sched_in.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-21 18:45:21 +02:00