At the moment kvmppc_mmu_map_page() returns -1 if
mmu_hash_ops.hpte_insert() fails for any reason so the page fault handler
resumes the guest and it faults on the same address again.
This adds distinction to kvmppc_mmu_map_page() to return -EIO if
mmu_hash_ops.hpte_insert() failed for a reason other than full pteg.
At the moment only pSeries_lpar_hpte_insert() returns -2 if
plpar_pte_enter() failed with a code other than H_PTEG_FULL.
Other mmu_hash_ops.hpte_insert() instances can only fail with
-1 "full pteg".
With this change, if PR KVM fails to update HPT, it can signal
the userspace about this instead of returning to guest and having
the very same page fault over and over again.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
@is_mmio has never been used since introduction in
commit 2f4cf5e42d ("Add book3s.c") from 2009.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kcalloc".
This issue was detected by using the Coccinelle software.
* Replace the specification of a data type by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Add a jump target so that a bit of exception handling can be better reused
at the end of this function.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
For completeness, this adds emulation of the lfiwax and lfiwzx
instructions. With this, all floating-point load and store instructions
as of Power ISA V2.07 are emulated.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds emulation for the following integer loads and stores,
thus enabling them to be used in a guest for accessing emulated
MMIO locations.
- lhaux
- lwaux
- lwzux
- ldu
- lwa
- stdux
- stwux
- stdu
- ldbrx
- stdbrx
Previously, most of these would cause an emulation failure exit to
userspace, though ldu and lwa got treated incorrectly as ld, and
stdu got treated incorrectly as std.
This also tidies up some of the formatting and updates the comment
listing instructions that still need to be implemented.
With this, all integer loads and stores that are defined in the Power
ISA v2.07 are emulated, except for those that are permitted to trap
when used on cache-inhibited or write-through mappings (and which do
in fact trap on POWER8), that is, lmw/stmw, lswi/stswi, lswx/stswx,
lq/stq, and l[bhwdq]arx/st[bhwdq]cx.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds missing stdx emulation for emulated MMIO accesses by KVM
guests. This allows the Mellanox mlx5_core driver from recent kernels
to work when MMIO emulation is enforced by userspace.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This patch provides the MMIO load/store emulation for instructions
of 'double & vector unsigned char & vector signed char & vector
unsigned short & vector signed short & vector unsigned int & vector
signed int & vector double '.
The instructions that this adds emulation for are:
- ldx, ldux, lwax,
- lfs, lfsx, lfsu, lfsux, lfd, lfdx, lfdu, lfdux,
- stfs, stfsx, stfsu, stfsux, stfd, stfdx, stfdu, stfdux, stfiwx,
- lxsdx, lxsspx, lxsiwax, lxsiwzx, lxvd2x, lxvw4x, lxvdsx,
- stxsdx, stxsspx, stxsiwx, stxvd2x, stxvw4x
[paulus@ozlabs.org - some cleanups, fixes and rework, make it
compile for Book E, fix build when PR KVM is built in]
Signed-off-by: Bin Lu <lblulb@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This provides functions that can be used for generating interrupts
indicating that a given functional unit (floating point, vector, or
VSX) is unavailable. These functions will be used in instruction
emulation code.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Frameworks that may want to enumerate CMA heaps (e.g. Ion) will find it
useful to have an explicit name attached to each region. Store the name
in each CMA structure.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This merges the arch part of the XIVE support, leaving the final commit
with the KVM specific pieces dangling on the branch for Paul to merge
via the kvm-ppc tree.
These files don't seem to have any need for asm/debug.h, now that all it
includes are the debugger hooks and breakpoint definitions.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc_debugfs_root is the dentry representing the root of the
"powerpc" directory tree in debugfs.
Currently it sits in asm/debug.h, a long with some other things that
have "debug" in the name, but are otherwise unrelated.
Pull it out into a separate header, which also includes linux/debugfs.h,
and convert all the users to include debugfs.h instead of debug.h.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We have all sort of variants of MMIO accessors for the real mode
instructions. This creates a clean set of accessors based on
Linux normal naming conventions, replacing all occurrences of
the old ones in the tree.
I have purposefully removed the "out/in" variants in favor of
only including __raw variants. Any code using these is already
pretty much hand tuned to operate in a very specific environment.
I've fixed up the 2 users (only one of them actually needed
a barrier in the first place).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It's only used within the same file it's defined
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We traditionally have linux/ before asm/
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The XIVE interrupt controller is the new interrupt controller
found in POWER9. It supports advanced virtualization capabilities
among other things.
Currently we use a set of firmware calls that simulate the old
"XICS" interrupt controller but this is fairly inefficient.
This adds the framework for using XIVE along with a native
backend which OPAL for configuration. Later, a backend allowing
the use in a KVM or PowerVM guest will also be provided.
This disables some fast path for interrupts in KVM when XIVE is
enabled as these rely on the firmware emulation code which is no
longer available when the XIVE is used natively by Linux.
A latter patch will make KVM also directly exploit the XIVE, thus
recovering the lost performance (and more).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Fixup pr_xxx("XIVE:"...), don't split pr_xxx() strings,
tweak Kconfig so XIVE_NATIVE selects XIVE and depends on POWERNV,
fix build errors when SMP=n, fold in fixes from Ben:
Don't call cpu_online() on an invalid CPU number
Fix irq target selection returning out of bounds cpu#
Extra sanity checks on cpu numbers
]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Remove code from architecture files that can be moved to virt/kvm, since there
is already common code for coalesced MMIO.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Removed a pointless 'break' after 'return'.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
kzalloc() won't actually fail because sizeof(*resize) is small, but
static checkers complain.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Inorder to support large effective address range (512TB), we want to
increase the virtual address bits to 68. But we do have platforms like
p4 and p5 that can only do 65 bit VA. We support those platforms by
limiting context bits on them to 16.
The protovsid -> vsid conversion is verified to work with both 65 and 68
bit va values. I also documented the restrictions in a table format as
part of code comments.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
KVM wants to be able to allocate an MMU context id, which it does
currently by calling __init_new_context().
We're about to rework that code, so provide a wrapper for KVM so it
can not worry about the details.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We use pte_write() to check whethwer the pte entry is writable. This is
mostly used to later mark the pte read only if it is writable. The other
use of pte_write() is to check whether the pte_entry is writable so that
hardware page table entry can be marked accordingly. This is used in kvm
where we look at qemu page table entry and update hardware hash page table
for the guest with correct write enable bit.
With the above, for the first usage we should also check the savedwrite
bit so that we can correctly clear the savedwite bit. For the later, we
add a new variant __pte_write().
With this we can revert write_protect_page part of 595cd8f256 ("mm/ksm:
handle protnone saved writes when making page write protect"). But I left
it as it is as an example code for savedwrite check.
Fixes: c137a2757b ("powerpc/mm/autonuma: switch ppc64 to its own implementation of saved write")
Link: http://lkml.kernel.org/r/1488203787-17849-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PPC:
* correct assumption about ASDR on POWER9
* fix MMIO emulation on POWER9
x86:
* add a simple test for ioperm
* cleanup TSS
(going through KVM tree as the whole undertaking was caused by VMX's
use of TSS)
* fix nVMX interrupt delivery
* fix some performance counters in the guest
And two cleanup patches.
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Merge tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Radim Krčmář:
"Second batch of KVM changes for the 4.11 merge window:
PPC:
- correct assumption about ASDR on POWER9
- fix MMIO emulation on POWER9
x86:
- add a simple test for ioperm
- cleanup TSS (going through KVM tree as the whole undertaking was
caused by VMX's use of TSS)
- fix nVMX interrupt delivery
- fix some performance counters in the guest
... and two cleanup patches"
* tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: nVMX: Fix pending events injection
x86/kvm/vmx: remove unused variable in segment_base()
selftests/x86: Add a basic selftest for ioperm
x86/asm: Tidy up TSS limit code
kvm: convert kvm.users_count from atomic_t to refcount_t
KVM: x86: never specify a sample period for virtualized in_tx_cp counters
KVM: PPC: Book3S HV: Don't use ASDR for real-mode HPT faults on POWER9
KVM: PPC: Book3S HV: Fix software walk of guest process page tables
We don't actually need the full rculist.h header in sched.h anymore,
we will be able to include the smaller rcupdate.h header instead.
But first update code that relied on the implicit header inclusion.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Update code that relied on sched.h including various MM types for them.
This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/stat.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/stat.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In HPT mode on POWER9, the ASDR register is supposed to record
segment information for hypervisor page faults. It turns out that
POWER9 DD1 does not record the page size information in the ASDR
for faults in guest real mode. We have the necessary information
in memory already, so by moving the checks for real mode that already
existed, we can use the in-memory copy. Since a load is likely to
be faster than reading an SPR, we do this unconditionally (not just
for POWER9 DD1).
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This fixes some bugs in the code that walks the guest's page tables.
These bugs cause MMIO emulation to fail whenever the guest is in
virtial mode (MMU on), leading to the guest hanging if it tried to
access a virtio device.
The first bug was that when reading the guest's process table, we were
using the whole of arch->process_table, not just the field that contains
the process table base address. The second bug was that the mask used
when reading the process table entry to get the radix tree base address,
RPDB_MASK, had the wrong value.
Fixes: 9e04ba69be ("KVM: PPC: Book3S HV: Add basic infrastructure for radix guests")
Fixes: e99833448c ("powerpc/mm/radix: Add partition table format & callback")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Most users of this interface just want to use it with the default
GFP_KERNEL flags, but for cases where DMA memory is allocated it may be
called from a different context.
No functional change yet, just passing through the flag to the
underlying alloc_contig_range function.
Link: http://lkml.kernel.org/r/20170127172328.18574-2-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.
Remove the vma parameter to simplify things.
[arnd@arndb.de: fix ARM build]
Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Mackerras writes:
"Please do a pull from my kvm-ppc-next branch to get some fixes which I
would like to have in 4.11. There are four small commits there; two
are fixes for potential host crashes in the new HPT resizing code, and
the other two are changes to printks to make KVM on PPC a little less
noisy."
The new HPT resizing code added in commit b5baa68773 ("KVM: PPC:
Book3S HV: KVM-HV HPT resizing implementation", 2016-12-20) doesn't
have code to handle the new HPTE format which POWER9 uses. Thus it
would be best not to advertise it to userspace on POWER9 systems
until it works properly.
Also, since resize_hpt_rehash_hpte() contains BUG_ON() calls that
could be hit on POWER9, let's prevent it from being called on POWER9
for now.
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The purpose of the KVM_SET_SIGNAL_MASK API is to let userspace "kick"
a VCPU out of KVM_RUN through a POSIX signal. A signal is attached
to a dummy signal handler; by blocking the signal outside KVM_RUN and
unblocking it inside, this possible race is closed:
VCPU thread service thread
--------------------------------------------------------------
check flag
set flag
raise signal
(signal handler does nothing)
KVM_RUN
However, one issue with KVM_SET_SIGNAL_MASK is that it has to take
tsk->sighand->siglock on every KVM_RUN. This lock is often on a
remote NUMA node, because it is on the node of a thread's creator.
Taking this lock can be very expensive if there are many userspace
exits (as is the case for SMP Windows VMs without Hyper-V reference
time counter).
As an alternative, we can put the flag directly in kvm_run so that
KVM can see it:
VCPU thread service thread
--------------------------------------------------------------
raise signal
signal handler
set run->immediate_exit
KVM_RUN
check run->immediate_exit
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The average user likely does not know what a "htab" or "LPID" is,
and it's annoying that these messages are quickly filling the dmesg
log when you're doing boot cycle tests, so let's turn it into a debug
message instead.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
kvm_ppc_mmu_book3s_32/64 xlat() logs "KVM can't copy data" error
upon failing to copy user data to kernel space. This floods kernel
log once such fails occur in short time period. Ratelimit this
error to avoid flooding kernel logs upon copy data failures.
Signed-off-by: Vipin K Parashar <vipin@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
resize_hpt_release(), called once the HPT resize of a KVM guest is
completed (successfully or unsuccessfully) frees the state structure for
the resize. It is currently not safe to call with a NULL pointer.
However, one of the error paths in kvm_vm_ioctl_resize_hpt_commit() can
invoke it with a NULL pointer. This will occur if userspace improperly
invokes KVM_PPC_RESIZE_HPT_COMMIT without previously calling
KVM_PPC_RESIZE_HPT_PREPARE, or if it calls COMMIT twice without an
intervening PREPARE.
To fix this potential crash bug - and maybe others like it, make it safe
(and a no-op) to call resize_hpt_release() with a NULL resize pointer.
Found by Dan Carpenter with a static checker.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Fix to return error code -ENOMEM from the memory alloc error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This merges in a fix which touches both PPC and KVM code,
which was therefore put into a topic branch in the powerpc
tree.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
All entry points already read the MSR so they can easily do
the right thing.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This updates the KVM_CAP_SPAPR_RESIZE_HPT capability to advertise the
presence of in-kernel HPT resizing on KVM HV.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds the "guts" of the implementation for the HPT resizing PAPR
extension. It has the code to allocate and clear a new HPT, rehash an
existing HPT's entries into it, and accomplish the switchover for a
KVM guest from the old HPT to the new one.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds a not yet working outline of the HPT resizing PAPR
extension. Specifically it adds the necessary ioctl() functions,
their basic steps, the work function which will handle preparation for
the resize, and synchronization between these, the guest page fault
path and guest HPT update path.
The actual guts of the implementation isn't here yet, so for now the
calls will always fail.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The kvm_unmap_rmapp() function, called from certain MMU notifiers, is used
to force all guest mappings of a particular host page to be set ABSENT, and
removed from the reverse mappings.
For HPT resizing, we will have some cases where we want to set just a
single guest HPTE ABSENT and remove its reverse mappings. To prepare with
this, we split out the logic from kvm_unmap_rmapp() to evict a single HPTE,
moving it to a new helper function.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The KVM_PPC_ALLOCATE_HTAB ioctl() is used to set the size of hashed page
table (HPT) that userspace expects a guest VM to have, and is also used to
clear that HPT when necessary (e.g. guest reboot).
At present, once the ioctl() is called for the first time, the HPT size can
never be changed thereafter - it will be cleared but always sized as from
the first call.
With upcoming HPT resize implementation, we're going to need to allow
userspace to resize the HPT at reset (to change it back to the default size
if the guest changed it).
So, we need to allow this ioctl() to change the HPT size.
This patch also updates Documentation/virtual/kvm/api.txt to reflect
the new behaviour. In fact the documentation was already slightly
incorrect since 572abd5 "KVM: PPC: Book3S HV: Don't fall back to
smaller HPT size in allocation ioctl"
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Currently, kvmppc_alloc_hpt() both allocates a new hashed page table (HPT)
and sets it up as the active page table for a VM. For the upcoming HPT
resize implementation we're going to want to allocate HPTs separately from
activating them.
So, split the allocation itself out into kvmppc_allocate_hpt() and perform
the activation with a new kvmppc_set_hpt() function. Likewise we split
kvmppc_free_hpt(), which just frees the HPT, from kvmppc_release_hpt()
which unsets it as an active HPT, then frees it.
We also move the logic to fall back to smaller HPT sizes if the first try
fails into the single caller which used that behaviour,
kvmppc_hv_setup_htab_rma(). This introduces a slight semantic change, in
that previously if the initial attempt at CMA allocation failed, we would
fall back to attempting smaller sizes with the page allocator. Now, we
try first CMA, then the page allocator at each size. As far as I can tell
this change should be harmless.
To match, we make kvmppc_free_hpt() just free the actual HPT itself. The
call to kvmppc_free_lpid() that was there, we move to the single caller.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Currently the kvm_hpt_info structure stores the hashed page table's order,
and also the number of HPTEs it contains and a mask for its size. The
last two can be easily derived from the order, so remove them and just
calculate them as necessary with a couple of helper inlines.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Currently, the powerpc kvm_arch structure contains a number of variables
tracking the state of the guest's hashed page table (HPT) in KVM HV. This
patch gathers them all together into a single kvm_hpt_info substructure.
This makes life more convenient for the upcoming HPT resizing
implementation.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The difference between kvm_alloc_hpt() and kvmppc_alloc_hpt() is not at
all obvious from the name. In practice kvmppc_alloc_hpt() allocates an HPT
by whatever means, and calls kvm_alloc_hpt() which will attempt to allocate
it with CMA only.
To make this less confusing, rename kvm_alloc_hpt() to kvm_alloc_hpt_cma().
Similarly, kvm_release_hpt() is renamed kvm_free_hpt_cma().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This merges in the POWER9 radix MMU host and guest support, which
was put into a topic branch because it touches both powerpc and
KVM code.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds a few last pieces of the support for radix guests:
* Implement the backends for the KVM_PPC_CONFIGURE_V3_MMU and
KVM_PPC_GET_RMMU_INFO ioctls for radix guests
* On POWER9, allow secondary threads to be on/off-lined while guests
are running.
* Set up LPCR and the partition table entry for radix guests.
* Don't allocate the rmap array in the kvm_memory_slot structure
on radix.
* Don't try to initialize the HPT for radix guests, since they don't
have an HPT.
* Take out the code that prevents the HV KVM module from
initializing on radix hosts.
At this stage, we only support radix guests if the host is running
in radix mode, and only support HPT guests if the host is running in
HPT mode. Thus a guest cannot switch from one mode to the other,
which enables some simplifications.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On POWER9 DD1, we need to invalidate the ERAT (effective to real
address translation cache) when changing the PIDR register, which
we do as part of guest entry and exit.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If we allow LPCR[AIL] to be set for radix guests, then interrupts from
the guest to the host can be delivered by the hardware with relocation
on, and thus the code path starting at kvmppc_interrupt_hv can be
executed in virtual mode (MMU on) for radix guests (previously it was
only ever executed in real mode).
Most of the code is indifferent to whether the MMU is on or off, but
the calls to OPAL that use the real-mode OPAL entry code need to
be switched to use the virtual-mode code instead. The affected
calls are the calls to the OPAL XICS emulation functions in
kvmppc_read_one_intr() and related functions. We test the MSR[IR]
bit to detect whether we are in real or virtual mode, and call the
opal_rm_* or opal_* function as appropriate.
The other place that depends on the MMU being off is the optimization
where the guest exit code jumps to the external interrupt vector or
hypervisor doorbell interrupt vector, or returns to its caller (which
is __kvmppc_vcore_entry). If the MMU is on and we are returning to
the caller, then we don't need to use an rfid instruction since the
MMU is already on; a simple blr suffices. If there is an external
or hypervisor doorbell interrupt to handle, we branch to the
relocation-on version of the interrupt vector.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
With radix, the guest can do TLB invalidations itself using the tlbie
(global) and tlbiel (local) TLB invalidation instructions. Linux guests
use local TLB invalidations for translations that have only ever been
accessed on one vcpu. However, that doesn't mean that the translations
have only been accessed on one physical cpu (pcpu) since vcpus can move
around from one pcpu to another. Thus a tlbiel might leave behind stale
TLB entries on a pcpu where the vcpu previously ran, and if that task
then moves back to that previous pcpu, it could see those stale TLB
entries and thus access memory incorrectly. The usual symptom of this
is random segfaults in userspace programs in the guest.
To cope with this, we detect when a vcpu is about to start executing on
a thread in a core that is a different core from the last time it
executed. If that is the case, then we mark the core as needing a
TLB flush and then send an interrupt to any thread in the core that is
currently running a vcpu from the same guest. This will get those vcpus
out of the guest, and the first one to re-enter the guest will do the
TLB flush. The reason for interrupting the vcpus executing on the old
core is to cope with the following scenario:
CPU 0 CPU 1 CPU 4
(core 0) (core 0) (core 1)
VCPU 0 runs task X VCPU 1 runs
core 0 TLB gets
entries from task X
VCPU 0 moves to CPU 4
VCPU 0 runs task X
Unmap pages of task X
tlbiel
(still VCPU 1) task X moves to VCPU 1
task X runs
task X sees stale TLB
entries
That is, as soon as the VCPU starts executing on the new core, it
could unmap and tlbiel some page table entries, and then the task
could migrate to one of the VCPUs running on the old core and
potentially see stale TLB entries.
Since the TLB is shared between all the threads in a core, we only
use the bit of kvm->arch.need_tlb_flush corresponding to the first
thread in the core. To ensure that we don't have a window where we
can miss a flush, this moves the clearing of the bit from before the
actual flush to after it. This way, two threads might both do the
flush, but we prevent the situation where one thread can enter the
guest before the flush is finished.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If the guest is in radix mode, then it doesn't have a hashed page
table (HPT), so all of the hypercalls that manipulate the HPT can't
work and should return an error. This adds checks to make them
return H_FUNCTION ("function not supported").
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds code to keep track of dirty pages when requested (that is,
when memslot->dirty_bitmap is non-NULL) for radix guests. We use the
dirty bits in the PTEs in the second-level (partition-scoped) page
tables, together with a bitmap of pages that were dirty when their
PTE was invalidated (e.g., when the page was paged out). This bitmap
is stored in the first half of the memslot->dirty_bitmap area, and
kvm_vm_ioctl_get_dirty_log_hv() now uses the second half for the
bitmap that gets returned to userspace.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adapts our implementations of the MMU notifier callbacks
(unmap_hva, unmap_hva_range, age_hva, test_age_hva, set_spte_hva)
to call radix functions when the guest is using radix. These
implementations are much simpler than for HPT guests because we
have only one PTE to deal with, so we don't need to traverse
rmap chains.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds the code to construct the second-level ("partition-scoped" in
architecturese) page tables for guests using the radix MMU. Apart from
the PGD level, which is allocated when the guest is created, the rest
of the tree is all constructed in response to hypervisor page faults.
As well as hypervisor page faults for missing pages, we also get faults
for reference/change (RC) bits needing to be set, as well as various
other error conditions. For now, we only set the R or C bit in the
guest page table if the same bit is set in the host PTE for the
backing page.
This code can take advantage of the guest being backed with either
transparent or ordinary 2MB huge pages, and insert 2MB page entries
into the guest page tables. There is no support for 1GB huge pages
yet.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds code to branch around the parts that radix guests don't
need - clearing and loading the SLB with the guest SLB contents,
saving the guest SLB contents on exit, and restoring the host SLB
contents.
Since the host is now using radix, we need to save and restore the
host value for the PID register.
On hypervisor data/instruction storage interrupts, we don't do the
guest HPT lookup on radix, but just save the guest physical address
for the fault (from the ASDR register) in the vcpu struct.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds a field in struct kvm_arch and an inline helper to
indicate whether a guest is a radix guest or not, plus a new file
to contain the radix MMU code, which currently contains just a
translate function which knows how to traverse the guest page
tables to translate an address.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
POWER9 adds a register called ASDR (Access Segment Descriptor
Register), which is set by hypervisor data/instruction storage
interrupts to contain the segment descriptor for the address
being accessed, assuming the guest is using HPT translation.
(For radix guests, it contains the guest real address of the
access.)
Thus, for HPT guests on POWER9, we can use this register rather
than looking up the SLB with the slbfee. instruction.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds the implementation of the KVM_PPC_CONFIGURE_V3_MMU ioctl
for HPT guests on POWER9. With this, we can return 1 for the
KVM_CAP_PPC_MMU_HASH_V3 capability.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds two capabilities and two ioctls to allow userspace to
find out about and configure the POWER9 MMU in a guest. The two
capabilities tell userspace whether KVM can support a guest using
the radix MMU, or using the hashed page table (HPT) MMU with a
process table and segment tables. (Note that the MMUs in the
POWER9 processor cores do not use the process and segment tables
when in HPT mode, but the nest MMU does).
The KVM_PPC_CONFIGURE_V3_MMU ioctl allows userspace to specify
whether a guest will use the radix MMU or the HPT MMU, and to
specify the size and location (in guest space) of the process
table.
The KVM_PPC_GET_RMMU_INFO ioctl gives userspace information about
the radix MMU. It returns a list of supported radix tree geometries
(base page size and number of bits indexed at each level of the
radix tree) and the encoding used to specify the various page
sizes for the TLB invalidate entry instruction.
Initially, both capabilities return 0 and the ioctls return -EINVAL,
until the necessary infrastructure for them to operate correctly
is added.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
64-bit Book3S exception handlers must find the dynamic kernel base
to add to the target address when branching beyond __end_interrupts,
in order to support kernel running at non-0 physical address.
Support this in KVM by branching with CTR, similarly to regular
interrupt handlers. The guest CTR saved in HSTATE_SCRATCH1 and
restored after the branch.
Without this, the host kernel hangs and crashes randomly when it is
running at a non-0 address and a KVM guest is started.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The function kvmppc_handle_exit_pr() is quite huge and thus hard to read,
and even contains a "spaghetti-code"-like goto between the different case
labels of the big switch statement. This can be made much more readable
by moving the code related to injecting program interrupts / instruction
emulation into a separate function instead.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The H_PROD hypercall is supposed to wake up an idle vcpu. We have
an implementation, but because Linux doesn't use it except when
doing cpu hotplug, it was never tested properly. AIX does use it,
and reported it broken. It turns out we were waking the wrong
vcpu (the one doing H_PROD, not the target of the prod) and we
weren't handling the case where the target needs an IPI to wake
it. Fix it by using the existing kvmppc_fast_vcpu_kick_hv()
function, which is intended for this kind of thing, and by using
the target vcpu not the current vcpu.
We were also not looking at the prodded flag when checking whether a
ceded vcpu should wake up, so this adds checks for the prodded flag
alongside the checks for pending exceptions.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Change the calling convention to put the trap number together with
CR in two halves of r12, which frees up HSTATE_SCRATCH2 in the HV
handler.
The 64-bit PR handler entry translates the calling convention back
to match the previous call convention (i.e., shared with 32-bit), for
simplicity.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch improves the code that takes lock twice to check the resend flag
and do the actual resending, by checking the resend flag locklessly, and
add a boolean parameter check_resend to icp_[rm_]deliver_irq(), so the
resend flag can be checked in the lock when doing the delivery.
We need make sure when we clear the ics's bit in the icp's resend_map, we
don't miss the resend flag of the irqs that set the bit. It could be
ordered through the barrier in test_and_clear_bit(), and a newly added
wmb between setting irq's resend flag, and icp's resend_map.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This patch implements P(Presented)/Q(Queued) states for ICS irqs.
When the interrupt is presented, set P. Present if P was not set.
If P is already set, don't present again, set Q.
When the interrupt is EOI'ed, move Q into P (and clear Q). If it is
set, re-present.
The asserted flag used by LSI is also incorporated into the P bit.
When the irq state is saved, P/Q bits are also saved, they need some
qemu modifications to be recognized and passed around to be restored.
KVM_XICS_PENDING bit set and saved should also indicate
KVM_XICS_PRESENTED bit set and saved. But it is possible some old
code doesn't have/recognize the P bit, so when we restore, we set P
for PENDING bit, too.
The idea and much of the code come from Ben.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
It is possible that in the following order, one irq is resent twice:
CPU 1 CPU 2
ics_check_resend()
lock ics_lock
see resend set
unlock ics_lock
/* change affinity of the irq */
kvmppc_xics_set_xive()
write_xive()
lock ics_lock
see resend set
unlock ics_lock
icp_deliver_irq() /* resend */
icp_deliver_irq() /* resend again */
It doesn't have any user-visible effect at present, but needs to be avoided
when the following patch implementing the P/Q stuff is applied.
This patch clears the resend flag before releasing the ics lock, when we
know we will do a re-delivery after checking the flag, or setting the flag.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Some counters are added in Commit 6e0365b782 ("KVM: PPC: Book3S HV:
Add ICP real mode counters"), to provide some performance statistics to
determine whether further optimizing is needed for real mode functions.
The n_reject counter counts how many times ICP rejects an irq because of
priority in real mode. The redelivery of an lsi that is still asserted
after eoi doesn't fall into this category, so the increasement there is
removed.
Also, it needs to be increased in icp_rm_deliver_irq() if it rejects
another one.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Commit b0221556db ("KVM: PPC: Book3S HV: Move virtual mode ICP functions
to real-mode") removed the setting of the XICS_RM_REJECT flag. And
since that commit, nothing else sets the flag any more, so we can remove
the flag and the remaining code that handles it, including the counter
that counts how many times it get set.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
If the target vcpu for kvmppc_fast_vcpu_kick_hv() is not running on
any CPU, then we will have vcpu->arch.thread_cpu == -1, and as it
happens, kvmppc_fast_vcpu_kick_hv will call kvmppc_ipi_thread with
-1 as the cpu argument. Although this is not meaningful, in the past,
before commit 1704a81cce ("KVM: PPC: Book3S HV: Use msgsnd for IPIs
to other cores on POWER9", 2016-11-18), it was harmless because CPU
-1 is not in the same core as any real CPU thread. On a POWER9,
however, we don't do the "same core" check, so we were trying to
do a msgsnd to thread -1, which is invalid. To avoid this, we add
a check to see that vcpu->arch.thread_cpu is >= 0 before calling
kvmppc_ipi_thread() with it. Since vcpu->arch.thread_vcpu can change
asynchronously, we use READ_ONCE to ensure that the value we check is
the same value that we use as the argument to kvmppc_ipi_thread().
Fixes: 1704a81cce ("KVM: PPC: Book3S HV: Use msgsnd for IPIs to other cores on POWER9")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
x86: userspace can now hide nested VMX features from guests; nested
VMX can now run Hyper-V in a guest; support for AVX512_4VNNIW and
AVX512_FMAPS in KVM; infrastructure support for virtual Intel GPUs.
PPC: support for KVM guests on POWER9; improved support for interrupt
polling; optimizations and cleanups.
s390: two small optimizations, more stuff is in flight and will be
in 4.11.
ARM: support for the GICv3 ITS on 32bit platforms.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"Small release, the most interesting stuff is x86 nested virt
improvements.
x86:
- userspace can now hide nested VMX features from guests
- nested VMX can now run Hyper-V in a guest
- support for AVX512_4VNNIW and AVX512_FMAPS in KVM
- infrastructure support for virtual Intel GPUs.
PPC:
- support for KVM guests on POWER9
- improved support for interrupt polling
- optimizations and cleanups.
s390:
- two small optimizations, more stuff is in flight and will be in
4.11.
ARM:
- support for the GICv3 ITS on 32bit platforms"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits)
arm64: KVM: pmu: Reset PMSELR_EL0.SEL to a sane value before entering the guest
KVM: arm/arm64: timer: Check for properly initialized timer on init
KVM: arm/arm64: vgic-v2: Limit ITARGETSR bits to number of VCPUs
KVM: x86: Handle the kthread worker using the new API
KVM: nVMX: invvpid handling improvements
KVM: nVMX: check host CR3 on vmentry and vmexit
KVM: nVMX: introduce nested_vmx_load_cr3 and call it on vmentry
KVM: nVMX: propagate errors from prepare_vmcs02
KVM: nVMX: fix CR3 load if L2 uses PAE paging and EPT
KVM: nVMX: load GUEST_EFER after GUEST_CR0 during emulated VM-entry
KVM: nVMX: generate MSR_IA32_CR{0,4}_FIXED1 from guest CPUID
KVM: nVMX: fix checks on CR{0,4} during virtual VMX operation
KVM: nVMX: support restore of VMX capability MSRs
KVM: nVMX: generate non-true VMX MSRs based on true versions
KVM: x86: Do not clear RFLAGS.TF when a singlestep trap occurs.
KVM: x86: Add kvm_skip_emulated_instruction and use it.
KVM: VMX: Move skip_emulated_instruction out of nested_vmx_check_vmcs12
KVM: VMX: Reorder some skip_emulated_instruction calls
KVM: x86: Add a return value to kvm_emulate_cpuid
KVM: PPC: Book3S: Move prototypes for KVM functions into kvm_ppc.h
...
Install the callbacks via the state machine.
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: kvm-ppc@vger.kernel.org
Cc: Paul Mackerras <paulus@samba.org>
Cc: rt@linutronix.de
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Link: http://lkml.kernel.org/r/20161126231350.10321-18-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This moves the prototypes for functions that are only called from
assembler code out of asm/asm-prototypes.h into asm/kvm_ppc.h.
The prototypes were added in commit ebe4535fbe ("KVM: PPC:
Book3S HV: sparse: prototypes for functions called from assembler",
2016-10-10), but given that the functions are KVM functions,
having them in a KVM header will be better for long-term
maintenance.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Fix comment block to match kernel comment style.
Fix print format from signed to unsigned.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The kvm module parameter halt_poll_ns defines the global maximum halt
polling interval and can be dynamically changed by writing to the
/sys/module/kvm/parameters/halt_poll_ns sysfs file. However in kvm-hv
this module parameter value is only ever checked when we grow the current
polling interval for the given vcore. This means that if we decrease the
halt_poll_ns value below the current polling interval we won't see any
effect unless we try to grow the polling interval above the new max at some
point or it happens to be shrunk below the halt_poll_ns value.
Update the halt polling code so that we always check for a new module param
value of halt_poll_ns and set the current halt polling interval to it if
it's currently greater than the new max. This means that it's redundant to
also perform this check in the grow_halt_poll_ns() function now.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The previous patch exported the variables which back the module parameters
of the generic kvm module. Now use these variables in the kvm-hv module
so that any change to the generic module parameters will also have the
same effect for the kvm-hv module. This removes the duplication of the
kvm module parameters which was redundant and should reduce confusion when
tuning them.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
At present KVM on powerpc always reports KVM_CAP_PPC_ALLOC_HTAB as enabled.
However, the ioctl() it advertises (KVM_PPC_ALLOCATE_HTAB) only actually
works on KVM HV. On KVM PR it will fail with ENOTTY.
QEMU already has a workaround for this, so it's not breaking things in
practice, but it would be better to advertise this correctly.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds the "again" parameter to the dummy version of
kvmppc_check_passthru(), so that it matches the real version.
This fixes compilation with CONFIG_BOOK3S_64_HV set but
CONFIG_KVM_XICS=n.
This includes asm/smp.h in book3s_hv_builtin.c to fix compilation
with CONFIG_SMP=n. The explicit inclusion is necessary to provide
definitions of hard_smp_processor_id() and get_hard_smp_processor_id()
in UP configs.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The function kvmppc_set_arch_compat() is used to determine the value of the
processor compatibility register (PCR) for a guest running in a given
compatibility mode. There is currently no support for v3.00 of the ISA.
Add support for v3.00 of the ISA which adds an ISA v2.07 compatilibity mode
to the PCR.
We also add a check to ensure the processor we are running on is capable of
emulating the chosen processor (for example a POWER7 cannot emulate a
POWER8, similarly with a POWER8 and a POWER9).
Based on work by: Paul Mackerras <paulus@ozlabs.org>
[paulus@ozlabs.org - moved dummy PCR_ARCH_300 definition here; set
guest_pcr_bit when arch_compat == 0, added comment.]
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
With POWER9, each CPU thread has its own MMU context and can be
in the host or a guest independently of the other threads; there is
still however a restriction that all threads must use the same type
of address translation, either radix tree or hashed page table (HPT).
Since we only support HPT guests on a HPT host at this point, we
can treat the threads as being independent, and avoid all of the
work of coordinating the CPU threads. To make this simpler, we
introduce a new threads_per_vcore() function that returns 1 on
POWER9 and threads_per_subcore on POWER7/8, and use that instead
of threads_per_subcore or threads_per_core in various places.
This also changes the value of the KVM_CAP_PPC_SMT capability on
POWER9 systems from 4 to 1, so that userspace will not try to
create VMs with multiple vcpus per vcore. (If userspace did create
a VM that thought it was in an SMT mode, the VM might try to use
the msgsndp instruction, which will not work as expected. In
future it may be possible to trap and emulate msgsndp in order to
allow VMs to think they are in an SMT mode, if only for the purpose
of allowing migration from POWER8 systems.)
With all this, we can now run guests on POWER9 as long as the host
is running with HPT translation. Since userspace currently has no
way to request radix tree translation for the guest, the guest has
no choice but to use HPT translation.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The new XIVE interrupt controller on POWER9 can direct external
interrupts to the hypervisor or the guest. The interrupts directed to
the hypervisor are controlled by an LPCR bit called LPCR_HVICE, and
come in as a "hypervisor virtualization interrupt". This sets the
LPCR bit so that hypervisor virtualization interrupts can occur while
we are in the guest. We then also need to cope with exiting the guest
because of a hypervisor virtualization interrupt.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
POWER9 replaces the various power-saving mode instructions on POWER8
(doze, nap, sleep and rvwinkle) with a single "stop" instruction, plus
a register, PSSCR, which controls the depth of the power-saving mode.
This replaces the use of the nap instruction when threads are idle
during guest execution with the stop instruction, and adds code to
set PSSCR to a value which will allow an SMT mode switch while the
thread is idle (given that the core as a whole won't be idle in these
cases).
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
POWER9 includes a new interrupt controller, called XIVE, which is
quite different from the XICS interrupt controller on POWER7 and
POWER8 machines. KVM-HV accesses the XICS directly in several places
in order to send and clear IPIs and handle interrupts from PCI
devices being passed through to the guest.
In order to make the transition to XIVE easier, OPAL firmware will
include an emulation of XICS on top of XIVE. Access to the emulated
XICS is via OPAL calls. The one complication is that the EOI
(end-of-interrupt) function can now return a value indicating that
another interrupt is pending; in this case, the XIVE will not signal
an interrupt in hardware to the CPU, and software is supposed to
acknowledge the new interrupt without waiting for another interrupt
to be delivered in hardware.
This adapts KVM-HV to use the OPAL calls on machines where there is
no XICS hardware. When there is no XICS, we look for a device-tree
node with "ibm,opal-intc" in its compatible property, which is how
OPAL indicates that it provides XICS emulation.
In order to handle the EOI return value, kvmppc_read_intr() has
become kvmppc_read_one_intr(), with a boolean variable passed by
reference which can be set by the EOI functions to indicate that
another interrupt is pending. The new kvmppc_read_intr() keeps
calling kvmppc_read_one_intr() until there are no more interrupts
to process. The return value from kvmppc_read_intr() is the
largest non-zero value of the returns from kvmppc_read_one_intr().
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
On POWER9, the msgsnd instruction is able to send interrupts to
other cores, as well as other threads on the local core. Since
msgsnd is generally simpler and faster than sending an IPI via the
XICS, we use msgsnd for all IPIs sent by KVM on POWER9.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
POWER9 adds new capabilities to the tlbie (TLB invalidate entry)
and tlbiel (local tlbie) instructions. Both instructions get a
set of new parameters (RIC, PRS and R) which appear as bits in the
instruction word. The tlbiel instruction now has a second register
operand, which contains a PID and/or LPID value if needed, and
should otherwise contain 0.
This adapts KVM-HV's usage of tlbie and tlbiel to work on POWER9
as well as older processors. Since we only handle HPT guests so
far, we need RIC=0 PRS=0 R=0, which ends up with the same instruction
word as on previous processors, so we don't need to conditionally
execute different instructions depending on the processor.
The local flush on first entry to a guest in book3s_hv_rmhandlers.S
is a loop which depends on the number of TLB sets. Rather than
using feature sections to set the number of iterations based on
which CPU we're on, we now work out this number at VM creation time
and store it in the kvm_arch struct. That will make it possible to
get the number from the device tree in future, which will help with
compatibility with future processors.
Since mmu_partition_table_set_entry() does a global flush of the
whole LPID, we don't need to do the TLB flush on first entry to the
guest on each processor. Therefore we don't set all bits in the
tlb_need_flush bitmap on VM startup on POWER9.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adds code to handle two new guest-accessible special-purpose
registers on POWER9: TIDR (thread ID register) and PSSCR (processor
stop status and control register). They are context-switched
between host and guest, and the guest values can be read and set
via the one_reg interface.
The PSSCR contains some fields which are guest-accessible and some
which are only accessible in hypervisor mode. We only allow the
guest-accessible fields to be read or set by userspace.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Some special-purpose registers that were present and accessible
by guests on POWER8 no longer exist on POWER9, so this adds
feature sections to ensure that we don't try to context-switch
them when going into or out of a guest on POWER9. These are
all relatively obscure, rarely-used registers, but we had to
context-switch them on POWER8 to avoid creating a covert channel.
They are: SPMC1, SPMC2, MMCRS, CSIGR, TACR, TCSCR, and ACOP.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
On POWER9, the SDR1 register (hashed page table base address) is no
longer used, and instead the hardware reads the HPT base address
and size from the partition table. The partition table entry also
contains the bits that specify the page size for the VRMA mapping,
which were previously in the LPCR. The VPM0 bit of the LPCR is
now reserved; the processor now always uses the VRMA (virtual
real-mode area) mechanism for guest real-mode accesses in HPT mode,
and the RMO (real-mode offset) mechanism has been dropped.
When entering or exiting the guest, we now only have to set the
LPIDR (logical partition ID register), not the SDR1 register.
There is also no requirement now to transition via a reserved
LPID value.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This adapts the KVM-HV hashed page table (HPT) code to read and write
HPT entries in the new format defined in Power ISA v3.00 on POWER9
machines. The new format moves the B (segment size) field from the
first doubleword to the second, and trims some bits from the AVA
(abbreviated virtual address) and ARPN (abbreviated real page number)
fields. As far as possible, the conversion is done when reading or
writing the HPT entries, and the rest of the code continues to use
the old format.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Drop duplicate header asm/iommu.h from book3s_64_vio_hv.c.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The hashed page table MMU in POWER processors can update the R
(reference) and C (change) bits in a HPTE at any time until the
HPTE has been invalidated and the TLB invalidation sequence has
completed. In kvmppc_h_protect, which implements the H_PROTECT
hypercall, we read the HPTE, modify the second doubleword,
invalidate the HPTE in memory, do the TLB invalidation sequence,
and then write the modified value of the second doubleword back
to memory. In doing so we could overwrite an R/C bit update done
by hardware between when we read the HPTE and when the TLB
invalidation completed. To fix this we re-read the second
doubleword after the TLB invalidation and OR in the (possibly)
new values of R and C. We can use an OR since hardware only ever
sets R and C, never clears them.
This race was found by code inspection. In principle this bug could
cause occasional guest memory corruption under host memory pressure.
Fixes: a8606e20e4 ("KVM: PPC: Handle some PAPR hcalls in the kernel", 2011-06-29)
Cc: stable@vger.kernel.org # v3.19+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
When switching from/to a guest that has a transaction in progress,
we need to save/restore the checkpointed register state. Although
XER is part of the CPU state that gets checkpointed, the code that
does this saving and restoring doesn't save/restore XER.
This fixes it by saving and restoring the XER. To allow userspace
to read/write the checkpointed XER value, we also add a new ONE_REG
specifier.
The visible effect of this bug is that the guest may see its XER
value being corrupted when it uses transactions.
Fixes: e4e3812150 ("KVM: PPC: Book3S HV: Add transactional memory support")
Fixes: 0a8eccefcb ("KVM: PPC: Book3S HV: Add missing code for transaction reclaim on guest exit")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This keeps a per vcpu cache for recently page faulted MMIO entries.
On a page fault, if the entry exists in the cache, we can avoid some
time-consuming paths, for example, looking up HPT, locking HPTE twice
and searching mmio gfn from memslots, then directly call
kvmppc_hv_emulate_mmio().
In current implenment, we limit the size of cache to four. We think
it's enough to cover the high-frequency MMIO HPTEs in most case.
For example, considering the case of using virtio device, for virtio
legacy devices, one HPTE could handle notifications from up to
1024 (64K page / 64 byte Port IO register) devices, so one cache entry
is enough; for virtio modern devices, we always need one HPTE to handle
notification for each device because modern device would use a 8M MMIO
register to notify host instead of Port IO register, typically the
system's configuration should not exceed four virtio devices per
vcpu, four cache entry is also enough in this case. Of course, if needed,
we could also modify the macro to a module parameter in the future.
Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Currently we mark a HPTE for emulated MMIO with HPTE_V_ABSENT bit
set as well as key 0x1f. However, those HPTEs may be conflicted with
the HPTE for real guest RAM page HPTE with key 0x1f when the page
get paged out.
This patch clears the key field of HPTE when the page is paged out,
then recover it when HPTE is re-established.
Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Using list_move_tail() instead of list_del() + list_add_tail().
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
A bunch of KVM functions are only called from assembler.
Give them prototypes in asm-prototypes.h
This reduces sparse warnings.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Squash a couple of sparse warnings by making things static.
Build tested.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Commit 5d375199ea ("KVM: PPC: Book3S HV: Set server for passed-through
interrupts") broke the SMP=n build:
arch/powerpc/kvm/book3s_hv_rm_xics.c:758:2: error: implicit declaration of function 'get_hard_smp_processor_id'
That is because we lost the implicit include of asm/smp.h, so include it
explicitly to get the definition for get_hard_smp_processor_id().
Fixes: 5d375199ea ("KVM: PPC: Book3S HV: Set server for passed-through interrupts")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The MMCR2 register is available twice, one time with number 785
(privileged access), and one time with number 769 (unprivileged,
but it can be disabled completely). In former times, the Linux
kernel was using the unprivileged register 769 only, but since
commit 8dd75ccb57 ("powerpc: Use privileged SPR number
for MMCR2"), it uses the privileged register 785 instead.
The KVM-PR code then of course also switched to use the SPR 785,
but this is causing older guest kernels to crash, since these
kernels still access 769 instead. So to support older kernels
with KVM-PR again, we have to support register 769 in KVM-PR, too.
Fixes: 8dd75ccb57
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
On POWER8E and POWER8NVL, KVM-PR does not announce support for
64kB page sizes and 1TB segments yet. Looks like this has just
been forgotton so far, since there is no reason why this should
be different to the normal POWER8 CPUs.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
We use logical negate where bitwise negate was intended. It means that
we never return -EINVAL here.
Fixes: ce11e48b7f ('KVM: PPC: E500: Add userspace debug stub support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This takes out the code that arranges to run two (or more) virtual
cores on a single subcore when possible, that is, when both vcores
are from the same VM, the VM is configured with one CPU thread per
virtual core, and all the per-subcore registers have the same value
in each vcore. Since the VTB (virtual timebase) is a per-subcore
register, and will almost always differ between vcores, this code
is disabled on POWER8 machines, meaning that it is only usable on
POWER7 machines (which don't have VTB). Given the tiny number of
POWER7 machines which have firmware that allows them to run HV KVM,
the benefit of simplifying the code outweighs the loss of this
feature on POWER7 machines.
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
POWER8 has one virtual timebase (VTB) register per subcore, not one
per CPU thread. The HV KVM code currently treats VTB as a per-thread
register, which can lead to spurious soft lockup messages from guests
which use the VTB as the time source for the soft lockup detector.
(CPUs before POWER8 did not have the VTB register.)
For HV KVM, this fixes the problem by making only the primary thread
in each virtual core save and restore the VTB value. With this,
the VTB state becomes part of the kvmppc_vcore structure. This
also means that "piggybacking" of multiple virtual cores onto one
subcore is not possible on POWER8, because then the virtual cores
would share a single VTB register.
PR KVM emulates a VTB register, which is per-vcpu because PR KVM
has no notion of CPU threads or SMT. For PR KVM we move the VTB
state into the kvmppc_vcpu_book3s struct.
Cc: stable@vger.kernel.org # v3.14+
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Two stubs are added:
o kvm_arch_has_vcpu_debugfs(): must return true if the arch
supports creating debugfs entries in the vcpu debugfs dir
(which will be implemented by the next commit)
o kvm_arch_create_vcpu_debugfs(): code that creates debugfs
entries in the vcpu debugfs dir
For x86, this commit introduces a new file to avoid growing
arch/x86/kvm/x86.c even more.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Adjust jump labels according to the current Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".
* Replace the specification of a data structure by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kcalloc".
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
This issue was detected also by using the Coccinelle software.
* Replace the specification of data structures by pointer dereferences
to make the corresponding size determination a bit safer according to
the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The local variable "g2h_bitmap" will be set to an appropriate value
a bit later. Thus omit the explicit initialisation at the beginning.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The kfree() function was called in two cases by the
kvm_vcpu_ioctl_config_tlb() function during error handling
even if the passed data structure element contained a null pointer.
* Split a condition check for memory allocation failures.
* Adjust jump targets according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".
This issue was detected by using the Coccinelle software.
* Replace the specification of a data type by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Add VCPU stat counters to track affinity for passthrough
interrupts.
pthru_all: Counts all passthrough interrupts whose IRQ mappings are
in the kvmppc_passthru_irq_map structure.
pthru_host: Counts all cached passthrough interrupts that were injected
from the host through kvm_set_irq (i.e. not handled in
real mode).
pthru_bad_aff: Counts how many cached passthrough interrupts have
bad affinity (receiving CPU is not running VCPU that is
the target of the virtual interrupt in the guest).
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
When a guest has a PCI pass-through device with an interrupt, it
will direct the interrupt to a particular guest VCPU. In fact the
physical interrupt might arrive on any CPU, and then get
delivered to the target VCPU in the emulated XICS (guest interrupt
controller), and eventually delivered to the target VCPU.
Now that we have code to handle device interrupts in real mode
without exiting to the host kernel, there is an advantage to having
the device interrupt arrive on the same sub(core) as the target
VCPU is running on. In this situation, the interrupt can be
delivered to the target VCPU without any exit to the host kernel
(using a hypervisor doorbell interrupt between threads if
necessary).
This patch aims to get passed-through device interrupts arriving
on the correct core by setting the interrupt server in the real
hardware XICS for the interrupt to the first thread in the (sub)core
where its target VCPU is running. We do this in the real-mode H_EOI
code because the H_EOI handler already needs to look at the
emulated ICS state for the interrupt (whereas the H_XIRR handler
doesn't), and we know we are running in the target VCPU context
at that point.
We set the server CPU in hardware using an OPAL call, regardless of
what the IRQ affinity mask for the interrupt says, and without
updating the affinity mask. This amounts to saying that when an
interrupt is passed through to a guest, as a matter of policy we
allow the guest's affinity for the interrupt to override the host's.
This is inspired by an earlier patch from Suresh Warrier, although
none of this code came from that earlier patch.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
When a passthrough IRQ is handled completely within KVM real
mode code, it has to also update the IRQ stats since this
does not go through the generic IRQ handling code.
However, the per CPU kstat_irqs field is an allocated (not static)
field and so cannot be directly accessed in real mode safely.
The function this_cpu_inc_rm() is introduced to safely increment
per CPU fields (currently coded for unsigned integers only) that
are allocated and could thus be vmalloced also.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Add a module parameter kvm_irq_bypass for kvm_hv.ko to
disable IRQ bypass for passthrough interrupts. The default
value of this tunable is 1 - that is enable the feature.
Since the tunable is used by built-in kernel code, we use
the module_param_cb macro to achieve this.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Dump the passthrough irqmap structure associated with a
guest as part of /sys/kernel/debug/powerpc/kvm-xics-*.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
In existing real mode ICP code, when updating the virtual ICP
state, if there is a required action that cannot be completely
handled in real mode, as for instance, a VCPU needs to be woken
up, flags are set in the ICP to indicate the required action.
This is checked when returning from hypercalls to decide whether
the call needs switch back to the host where the action can be
performed in virtual mode. Note that if h_ipi_redirect is enabled,
real mode code will first try to message a free host CPU to
complete this job instead of returning the host to do it ourselves.
Currently, the real mode PCI passthrough interrupt handling code
checks if any of these flags are set and simply returns to the host.
This is not good enough as the trap value (0x500) is treated as an
external interrupt by the host code. It is only when the trap value
is a hypercall that the host code searches for and acts on unfinished
work by calling kvmppc_xics_rm_complete.
This patch introduces a special trap BOOK3S_INTERRUPT_HV_RM_HARD
which is returned by KVM if there is unfinished business to be
completed in host virtual mode after handling a PCI passthrough
interrupt. The host checks for this special interrupt condition
and calls into the kvmppc_xics_rm_complete, which is made an
exported function for this reason.
[paulus@ozlabs.org - moved logic to set r12 to BOOK3S_INTERRUPT_HV_RM_HARD
in book3s_hv_rmhandlers.S into the end of kvmppc_check_wake_reason.]
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Currently, KVM switches back to the host to handle any external
interrupt (when the interrupt is received while running in the
guest). This patch updates real-mode KVM to check if an interrupt
is generated by a passthrough adapter that is owned by this guest.
If so, the real mode KVM will directly inject the corresponding
virtual interrupt to the guest VCPU's ICS and also EOI the interrupt
in hardware. In short, the interrupt is handled entirely in real
mode in the guest context without switching back to the host.
In some rare cases, the interrupt cannot be completely handled in
real mode, for instance, a VCPU that is sleeping needs to be woken
up. In this case, KVM simply switches back to the host with trap
reason set to 0x500. This works, but it is clearly not very efficient.
A following patch will distinguish this case and handle it
correctly in the host. Note that we can use the existing
check_too_hard() routine even though we are not in a hypercall to
determine if there is unfinished business that needs to be
completed in host virtual mode.
The patch assumes that the mapping between hardware interrupt IRQ
and virtual IRQ to be injected to the guest already exists for the
PCI passthrough interrupts that need to be handled in real mode.
If the mapping does not exist, KVM falls back to the default
existing behavior.
The KVM real mode code reads mappings from the mapped array in the
passthrough IRQ map without taking any lock. We carefully order the
loads and stores of the fields in the kvmppc_irq_map data structure
using memory barriers to avoid an inconsistent mapping being seen by
the reader. Thus, although it is possible to miss a map entry, it is
not possible to read a stale value.
[paulus@ozlabs.org - get irq_chip from irq_map rather than pimap,
pulled out powernv eoi change into a separate patch, made
kvmppc_read_intr get the vcpu from the paca rather than being
passed in, rewrote the logic at the end of kvmppc_read_intr to
avoid deep indentation, simplified logic in book3s_hv_rmhandlers.S
since we were always restoring SRR0/1 anyway, get rid of the cached
array (just use the mapped array), removed the kick_all_cpus_sync()
call, clear saved_xirr PACA field when we handle the interrupt in
real mode, fix compilation with CONFIG_KVM_XICS=n.]
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Add the irq_bypass_add_producer and irq_bypass_del_producer
functions. These functions get called whenever a GSI is being
defined for a guest. They create/remove the mapping between
host real IRQ numbers and the guest GSI.
Add the following helper functions to manage the
passthrough IRQ map.
kvmppc_set_passthru_irq()
Creates a mapping in the passthrough IRQ map that maps a host
IRQ to a guest GSI. It allocates the structure (one per guest VM)
the first time it is called.
kvmppc_clr_passthru_irq()
Removes the passthrough IRQ map entry given a guest GSI.
The passthrough IRQ map structure is not freed even when the
number of mapped entries goes to zero. It is only freed when
the VM is destroyed.
[paulus@ozlabs.org - modified to use is_pnv_opal_msi() rather than
requiring all passed-through interrupts to use the same irq_chip;
changed deletion so it zeroes out the r_hwirq field rather than
copying the last entry down and decrementing the number of entries.]
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This patch introduces an IRQ mapping structure, the
kvmppc_passthru_irqmap structure that is to be used
to map the real hardware IRQ in the host with the virtual
hardware IRQ (gsi) that is injected into a guest by KVM for
passthrough adapters.
Currently, we assume a separate IRQ mapping structure for
each guest. Each kvmppc_passthru_irqmap has a mapping arrays,
containing all defined real<->virtual IRQs.
[paulus@ozlabs.org - removed irq_chip field from struct
kvmppc_passthru_irqmap; changed parameter for
kvmppc_get_passthru_irqmap from struct kvm_vcpu * to struct
kvm *, removed small cached array.]
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Select IRQ_BYPASS_MANAGER for PPC when CONFIG_KVM is set.
Add the PPC producer functions for add and del producer.
[paulus@ozlabs.org - Moved new functions from book3s.c to powerpc.c
so booke compiles; added kvm_arch_has_irq_bypass implementation.]
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Modify kvmppc_read_intr to make it a C function. Because it is called
from kvmppc_check_wake_reason, any of the assembler code that calls
either kvmppc_read_intr or kvmppc_check_wake_reason now has to assume
that the volatile registers might have been modified.
This also adds in the optimization of clearing saved_xirr in the case
where we completely handle and EOI an IPI. Without this, the next
device interrupt will require two trips through the host interrupt
handling code.
[paulus@ozlabs.org - made kvmppc_check_wake_reason create a stack frame
when it is calling kvmppc_read_intr, which means we can set r12 to
the trap number (0x500) after the call to kvmppc_read_intr, instead
of using r31. Also moved the deliver_guest_interrupt label so as to
restore XER and CTR, plus other minor tweaks.]
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This merges the topic branch 'kvm-ppc-infrastructure' into kvm-ppc-next
so that I can then apply further patches that need the changes in the
kvm-ppc-infrastructure branch.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
hmi.c functions are unused unless sibling_subcore_state is nonzero, and
that in turn happens only if KVM is in use. So move the code to
arch/powerpc/kvm/, putting it under CONFIG_KVM_BOOK3S_HV_POSSIBLE
rather than CONFIG_PPC_BOOK3S_64. The sibling_subcore_state is also
included in struct paca_struct only if KVM is supported by the kernel.
Cc: Daniel Axtens <dja@axtens.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: kvm-ppc@vger.kernel.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
vcpu stats are used to collect information about a vcpu which can be viewed
in the debugfs. For example halt_attempted_poll and halt_successful_poll
are used to keep track of the number of times the vcpu attempts to and
successfully polls. These stats are currently not used on powerpc.
Implement incrementation of the halt_attempted_poll and
halt_successful_poll vcpu stats for powerpc. Since these stats are summed
over all the vcpus for all running guests it doesn't matter which vcpu
they are attributed to, thus we choose the current runner vcpu of the
vcore.
Also add new vcpu stats: halt_poll_success_ns, halt_poll_fail_ns and
halt_wait_ns to be used to accumulate the total time spend polling
successfully, polling unsuccessfully and waiting respectively, and
halt_successful_wait to accumulate the number of times the vcpu waits.
Given that halt_poll_success_ns, halt_poll_fail_ns and halt_wait_ns are
expressed in nanoseconds it is necessary to represent these as 64-bit
quantities, otherwise they would overflow after only about 4 seconds.
Given that the total time spend either polling or waiting will be known and
the number of times that each was done, it will be possible to determine
the average poll and wait times. This will give the ability to tune the kvm
module parameters based on the calculated average wait and poll times.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This patch introduces new halt polling functionality into the kvm_hv kernel
module. When a vcore is idle it will poll for some period of time before
scheduling itself out.
When all of the runnable vcpus on a vcore have ceded (and thus the vcore is
idle) we schedule ourselves out to allow something else to run. In the
event that we need to wake up very quickly (for example an interrupt
arrives), we are required to wait until we get scheduled again.
Implement halt polling so that when a vcore is idle, and before scheduling
ourselves, we poll for vcpus in the runnable_threads list which have
pending exceptions or which leave the ceded state. If we poll successfully
then we can get back into the guest very quickly without ever scheduling
ourselves, otherwise we schedule ourselves out as before.
There exists generic halt_polling code in virt/kvm_main.c, however on
powerpc the polling conditions are different to the generic case. It would
be nice if we could just implement an arch specific kvm_check_block()
function, but there is still other arch specific things which need to be
done for kvm_hv (for example manipulating vcore states) which means that a
separate implementation is the best option.
Testing of this patch with a TCP round robin test between two guests with
virtio network interfaces has found a decrease in round trip time of ~15us
on average. A performance gain is only seen when going out of and
back into the guest often and quickly, otherwise there is no net benefit
from the polling. The polling interval is adjusted such that when we are
often scheduled out for long periods of time it is reduced, and when we
often poll successfully it is increased. The rate at which the polling
interval increases or decreases, and the maximum polling interval, can
be set through module parameters.
Based on the implementation in the generic kvm module by Wanpeng Li and
Paolo Bonzini, and on direction from Paul Mackerras.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The struct kvmppc_vcore is a structure used to store various information
about a virtual core for a kvm guest. The runnable_threads element of the
struct provides a list of all of the currently runnable vcpus on the core
(those in the KVMPPC_VCPU_RUNNABLE state). The previous implementation of
this list was a linked_list. The next patch requires that the list be able
to be iterated over without holding the vcore lock.
Reimplement the runnable_threads list in the kvmppc_vcore struct as an
array. Implement function to iterate over valid entries in the array and
update access sites accordingly.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
As discussed recently on the kvm mailing list, David Gibson's
intention in commit 178a787502 ("vfio: Enable VFIO device for
powerpc", 2016-02-01) was to have the KVM VFIO device built in
on all powerpc platforms. This patch adds the "select KVM_VFIO"
statement that makes this happen.
Currently, arch/powerpc/kvm/Makefile doesn't include vfio.o for
the 64-bit kvm module, because the list of objects doesn't use
the $(common-objs-y) list. The reason it doesn't is because we
don't necessarily want coalesced_mmio.o or emulate.o (for example
if HV KVM is the only target), and common-objs-y includes both.
Since this is confusing, this patch adjusts the definitions so that
we now use $(common-objs-y) in the list for the 64-bit kvm.ko
module, emulate.o is removed from common-objs-y and added in the
places that need it, and the inclusion of coalesced_mmio.o now
depends on CONFIG_KVM_MMIO.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
It doesn't make sense to create irqfds for a VM that doesn't have
in-kernel interrupt controller emulation. There is an existing
interface for architecture code to tell the irqfd code whether or
not any interrupt controller has been initialized, called
kvm_arch_intc_initialized(), so let's implement that for powerpc.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
It turns out that if userspace creates a pseries-type VM without
in-kernel XICS (interrupt controller) emulation, and then connects
an eventfd to the VM as an irqfd, and the eventfd gets signalled,
that the code will try to deliver an interrupt via the non-existent
XICS object and crash the host kernel with a NULL pointer dereference.
To fix this, we check for the presence of the XICS object before
trying to deliver the interrupt, and return with an error if not.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.
Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.
The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.
Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Pull kbuild updates from Michal Marek:
- GCC plugin support by Emese Revfy from grsecurity, with a fixup from
Kees Cook. The plugins are meant to be used for static analysis of
the kernel code. Two plugins are provided already.
- reduction of the gcc commandline by Arnd Bergmann.
- IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada
- bin2c fix by Michael Tautschnig
- setlocalversion fix by Wolfram Sang
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
gcc-plugins: disable under COMPILE_TEST
kbuild: Abort build on bad stack protector flag
scripts: Fix size mismatch of kexec_purgatory_size
kbuild: make samples depend on headers_install
Kbuild: don't add obj tree in additional includes
Kbuild: arch: look for generated headers in obtree
Kbuild: always prefix objtree in LINUXINCLUDE
Kbuild: avoid duplicate include path
Kbuild: don't add ../../ to include path
vmlinux.lds.h: replace config_enabled() with IS_ENABLED()
kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
kconfig.h: use already defined macros for IS_REACHABLE() define
export.h: use __is_defined() to check if __KSYM_* is defined
kconfig.h: use __is_defined() to check if MODULE is defined
kbuild: setlocalversion: print error to STDERR
Add sancov plugin
Add Cyclomatic complexity GCC plugin
GCC plugin infrastructure
Shared library support
VGIC implementation.
- s390: support for trapping software breakpoints, nested virtualization
(vSIE), the STHYI opcode, initial extensions for CPU model support.
- MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
preliminary to this and the upcoming support for hardware virtualization
extensions.
- x86: support for execute-only mappings in nested EPT; reduced vmexit
latency for TSC deadline timer (by about 30%) on Intel hosts; support for
more than 255 vCPUs.
- PPC: bugfixes.
The ugly bit is the conflicts. A couple of them are simple conflicts due
to 4.7 fixes, but most of them are with other trees. There was definitely
too much reliance on Acked-by here. Some conflicts are for KVM patches
where _I_ gave my Acked-by, but the worst are for this pull request's
patches that touch files outside arch/*/kvm. KVM submaintainers should
probably learn to synchronize better with arch maintainers, with the
latter providing topic branches whenever possible instead of Acked-by.
This is what we do with arch/x86. And I should learn to refuse pull
requests when linux-next sends scary signals, even if that means that
submaintainers have to rebase their branches.
Anyhow, here's the list:
- arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
by the nvdimm tree. This tree adds handle_preemption_timer and
EXIT_REASON_PREEMPTION_TIMER at the same place. In general all mentions
of pcommit have to go.
There is also a conflict between a stable fix and this patch, where the
stable fix removed the vmx_create_pml_buffer function and its call.
- virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
This tree adds kvm_io_bus_get_dev at the same place.
- virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
file was completely removed for 4.8.
- include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
this is a change that should have gone in through the irqchip tree and
pulled by kvm-arm. I think I would have rejected this kvm-arm pull
request. The KVM version is the right one, except that it lacks
GITS_BASER_PAGES_SHIFT.
- arch/powerpc: what a mess. For the idle_book3s.S conflict, the KVM
tree is the right one; everything else is trivial. In this case I am
not quite sure what went wrong. The commit that is causing the mess
(fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
and arch/powerpc/kvm/. It's large, but at 396 insertions/5 deletions
I guessed that it wasn't really possible to split it and that the 5
deletions wouldn't conflict. That wasn't the case.
- arch/s390: also messy. First is hypfs_diag.c where the KVM tree
moved some code and the s390 tree patched it. You have to reapply the
relevant part of commits 6c22c98637, plus all of e030c1125e, to
arch/s390/kernel/diag.c. Or pick the linux-next conflict
resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
Second, there is a conflict in gmap.c between a stable fix and 4.8.
The KVM version here is the correct one.
I have pushed my resolution at refs/heads/merge-20160802 (commit
3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
- ARM: GICv3 ITS emulation and various fixes. Removal of the
old VGIC implementation.
- s390: support for trapping software breakpoints, nested
virtualization (vSIE), the STHYI opcode, initial extensions
for CPU model support.
- MIPS: support for MIPS64 hosts (32-bit guests only) and lots
of cleanups, preliminary to this and the upcoming support for
hardware virtualization extensions.
- x86: support for execute-only mappings in nested EPT; reduced
vmexit latency for TSC deadline timer (by about 30%) on Intel
hosts; support for more than 255 vCPUs.
- PPC: bugfixes.
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
KVM: PPC: Introduce KVM_CAP_PPC_HTM
MIPS: Select HAVE_KVM for MIPS64_R{2,6}
MIPS: KVM: Reset CP0_PageMask during host TLB flush
MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
MIPS: KVM: Sign extend MFC0/RDHWR results
MIPS: KVM: Fix 64-bit big endian dynamic translation
MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
MIPS: KVM: Use 64-bit CP0_EBase when appropriate
MIPS: KVM: Set CP0_Status.KX on MIPS64
MIPS: KVM: Make entry code MIPS64 friendly
MIPS: KVM: Use kmap instead of CKSEG0ADDR()
MIPS: KVM: Use virt_to_phys() to get commpage PFN
MIPS: Fix definition of KSEGX() for 64-bit
KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
kvm: x86: nVMX: maintain internal copy of current VMCS
KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
KVM: arm64: vgic-its: Simplify MAPI error handling
KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
...
Introduce a new KVM capability, KVM_CAP_PPC_HTM, that can be queried to
determine if a PowerPC KVM guest should use HTM (Hardware Transactional
Memory).
This will be used by QEMU to populate the pa-features bits in the
guest's device tree.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It turns out that if the guest does a H_CEDE while the CPU is in
a transactional state, and the H_CEDE does a nap, and the nap
loses the architected state of the CPU (which is is allowed to do),
then we lose the checkpointed state of the virtual CPU. In addition,
the transactional-memory state recorded in the MSR gets reset back
to non-transactional, and when we try to return to the guest, we take
a TM bad thing type of program interrupt because we are trying to
transition from non-transactional to transactional with a hrfid
instruction, which is not permitted.
The result of the program interrupt occurring at that point is that
the host CPU will hang in an infinite loop with interrupts disabled.
Thus this is a denial of service vulnerability in the host which can
be triggered by any guest (and depending on the guest kernel, it can
potentially triggered by unprivileged userspace in the guest).
This vulnerability has been assigned the ID CVE-2016-5412.
To fix this, we save the TM state before napping and restore it
on exit from the nap, when handling a H_CEDE in real mode. The
case where H_CEDE exits to host virtual mode is already OK (as are
other hcalls which exit to host virtual mode) because the exit
path saves the TM state.
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This moves the transactional memory state save and restore sequences
out of the guest entry/exit paths into separate procedures. This is
so that these sequences can be used in going into and out of nap
in a subsequent patch.
The only code changes here are (a) saving and restore LR on the
stack, since these new procedures get called with a bl instruction,
(b) explicitly saving r1 into the PACA instead of assuming that
HSTATE_HOST_R1(r13) is already set, and (c) removing an unnecessary
and redundant setting of MSR[TM] that should have been removed by
commit 9d4d0bdd9e0a ("KVM: PPC: Book3S HV: Add transactional memory
support", 2013-09-24) but wasn't.
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Moving probe_machine() to after mmu init will cause the ppc_md
fields relative to the hash table management to be overwritten.
Since we have essentially disconnected the machine type from
the hash backend ops, finish the job by moving them to a different
structure.
The only callback that didn't quite fix is update_partition_table
since this is not specific to hash, so I moved it to a standalone
variable for now. We can revisit later if needed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Fix ppc64e build failure in kexec]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The various calls to establish exception endianness and AIL are
now done from a single point using already established CPU and FW
feature bits to decide what to do.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There are very few files that need add an -I$(obj) gcc for the preprocessor
or the assembler. For C files, we add always these for both the objtree and
srctree, but for the other ones we require the Makefile to add them, and
Kbuild then adds it for both trees.
As a preparation for changing the meaning of the -I$(obj) directive to
only refer to the srctree, this changes the two instances in arch/x86 to use
an explictit $(objtree) prefix where needed, otherwise we won't find the
headers any more, as reported by the kbuild 0day builder.
arch/x86/realmode/rm/realmode.lds.S:75:20: fatal error: pasyms.h: No such file or directory
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
Functions like power7_wakeup_loss, power7_wakeup_noloss,
power7_wakeup_tb_loss are used by POWER7 and POWER8 hardware. They can
also be used by POWER9. Hence rename these functions hardware agnostic
names.
Suggested-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
kvmppc_h_put_tce_indirect labels a u64 pointer as __user. It also
labelled the u64 where get_user puts the result as __user. This isn't
a pointer and so doesn't need to be labelled __user.
Split the u64 value definition onto a new line to make it clear that
it doesn't get the annotation.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Use the functions from context_tracking.h directly.
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
