Commit Graph

407 Commits

Author SHA1 Message Date
Ian Campbell
e68266b700 x86: xen: 64-bit kernel RPL should be 0
Under Xen 64 bit guests actually run their kernel in ring 3,
however the hypervisor takes care of squashing descriptor the
RPLs transparently (in order to allow them to continue to
differentiate between user and kernel space CS using the RPL).
Therefore the Xen paravirt backend should use RPL==0 instead of
1 (or 3). Using RPL==1 causes generic arch code to take
incorrect code paths because it uses "testl $3, <CS>, je foo"
type tests for a userspace CS and this considers 1==userspace.

This issue was previously masked because get_kernel_rpl() was
omitted when setting CS in kernel_thread(). This was fixed when
kernel_thread() was unified with 32 bit in
f443ff4201.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1263377768-19600-2-git-send-email-ian.campbell@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 11:23:54 +01:00
Thomas Gleixner
445c89514b locking: Convert raw_spinlock to arch_spinlock
The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.

Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
2009-12-14 23:55:32 +01:00
Linus Torvalds
d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
Linus Torvalds
11bd04f6f3 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (109 commits)
  PCI: fix coding style issue in pci_save_state()
  PCI: add pci_request_acs
  PCI: fix BUG_ON triggered by logical PCIe root port removal
  PCI: remove ifdefed pci_cleanup_aer_correct_error_status
  PCI: unconditionally clear AER uncorr status register during cleanup
  x86/PCI: claim SR-IOV BARs in pcibios_allocate_resource
  PCI: portdrv: remove redundant definitions
  PCI: portdrv: remove unnecessary struct pcie_port_data
  PCI: portdrv: minor cleanup for pcie_port_device_register
  PCI: portdrv: add missing irq cleanup
  PCI: portdrv: enable device before irq initialization
  PCI: portdrv: cleanup service irqs initialization
  PCI: portdrv: check capabilities first
  PCI: portdrv: move PME capability check
  PCI: portdrv: remove redundant pcie type calculation
  PCI: portdrv: cleanup pcie_device registration
  PCI: portdrv: remove redundant pcie_port_device_probe
  PCI: Always set prefetchable base/limit upper32 registers
  PCI: read-modify-write the pcie device control register when initiating pcie flr
  PCI: show dma_mask bits in /sys
  ...

Fixed up conflicts in:
	arch/x86/kernel/amd_iommu_init.c
	drivers/pci/dmar.c
	drivers/pci/hotplug/acpiphp_glue.c
2009-12-11 12:18:16 -08:00
Linus Torvalds
ab1831b0b8 Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen: try harder to balloon up under memory pressure.
  Xen balloon: fix totalram_pages counting.
  xen: explicitly create/destroy stop_machine workqueues outside suspend/resume region.
  xen: improve error handling in do_suspend.
  xen: don't leak IRQs over suspend/resume.
  xen: call clock resume notifier on all CPUs
  xen: use iret for return from 64b kernel to 32b usermode
  xen: don't call dpm_resume_noirq() with interrupts disabled.
  xen: register runstate info for boot CPU early
  xen: register runstate on secondary CPUs
  xen: register timer interrupt with IRQF_TIMER
  xen: correctly restore pfn_to_mfn_list_list after resume
  xen: restore runstate_info even if !have_vcpu_info_placement
  xen: re-register runstate area earlier on resume.
  xen: wait up to 5 minutes for device connetion
  xen: improvement to wait_for_devices()
  xen: fix is_disconnected_device/exists_disconnected_device
  xen/xenbus: make DEVICE_ATTR()s static
2009-12-10 09:35:02 -08:00
Linus Torvalds
3ff6a468b4 Merge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  cpumask: Use modern cpumask style in Xen
2009-12-08 13:38:33 -08:00
Linus Torvalds
e33c019722 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (36 commits)
  x86, mm: Correct the implementation of is_untracked_pat_range()
  x86/pat: Trivial: don't create debugfs for memtype if pat is disabled
  x86, mtrr: Fix sorting of mtrr after subtracting
  x86: Move find_smp_config() earlier and avoid bootmem usage
  x86, platform: Change is_untracked_pat_range() to bool; cleanup init
  x86: Change is_ISA_range() into an inline function
  x86, mm: is_untracked_pat_range() takes a normal semiclosed range
  x86, mm: Call is_untracked_pat_range() rather than is_ISA_range()
  x86: UV SGI: Don't track GRU space in PAT
  x86: SGI UV: Fix BAU initialization
  x86, numa: Use near(er) online node instead of roundrobin for NUMA
  x86, numa, bootmem: Only free bootmem on NUMA failure path
  x86: Change crash kernel to reserve via reserve_early()
  x86: Eliminate redundant/contradicting cache line size config options
  x86: When cleaning MTRRs, do not fold WP into UC
  x86: remove "extern" from function prototypes in <asm/proto.h>
  x86, mm: Report state of NX protections during boot
  x86, mm: Clean up and simplify NX enablement
  x86, pageattr: Make set_memory_(x|nx) aware of NX support
  x86, sleep: Always save the value of EFER
  ...

Fix up conflicts (added both iommu_shutdown and is_untracked_pat_range)
to 'struct x86_platform_ops') in
	arch/x86/include/asm/x86_init.h
	arch/x86/kernel/x86_init.c
2009-12-08 13:27:33 -08:00
Chris Wright
5d990b6275 PCI: add pci_request_acs
Commit ae21ee65e8 "PCI: acs p2p upsteram
forwarding enabling" doesn't actually enable ACS.

Add a function to pci core to allow an IOMMU to request that ACS
be enabled.  The existing mechanism of using iommu_found() in the pci
core to know when ACS should be enabled doesn't actually work due to
initialization order;  iommu has only been detected not initialized.

Have Intel and AMD IOMMUs request ACS, and Xen does as well during early
init of dom0.

Cc: Allen Kay <allen.m.kay@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-12-04 16:19:24 -08:00
Ian Campbell
f6eafe3665 xen: call clock resume notifier on all CPUs
tick_resume() is never called on secondary processors. Presumably this
is because they are offlined for suspend on native and so this is
normally taken care of in the CPU onlining path. Under Xen we keep all
CPUs online over a suspend.

This patch papers over the issue for me but I will investigate a more
generic, less hacky, way of doing to the same.

tick_suspend is also only called on the boot CPU which I presume should
be fixed too.

Signed-off-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2009-12-03 11:14:55 -08:00
Jeremy Fitzhardinge
6aaf5d633b xen: use iret for return from 64b kernel to 32b usermode
If Xen wants to return to a 32b usermode with sysret it must use the
right form.  When using VCGF_in_syscall to trigger this, it looks at
the code segment and does a 32b sysret if it is FLAT_USER_CS32.
However, this is different from __USER32_CS, so it fails to return
properly if we use the normal Linux segment.

So avoid the whole mess by dropping VCGF_in_syscall and simply use
plain iret to return to usermode.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Jan Beulich <jbeulich@novell.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:54 -08:00
Jeremy Fitzhardinge
499d19b82b xen: register runstate info for boot CPU early
printk timestamping uses sched_clock, which in turn relies on runstate
info under Xen.  So make sure we set it up before any printks can
be called.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:53 -08:00
Ian Campbell
028896721a xen: register runstate on secondary CPUs
The commit "xen: re-register runstate area earlier on resume" caused us
to never try and setup the runstate area for secondary CPUs. Ensure that
we do this...

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:52 -08:00
Ian Campbell
f350c7922f xen: register timer interrupt with IRQF_TIMER
Otherwise the timer is disabled by dpm_suspend_noirq() which in turn prevents
correct operation of stop_machine on multi-processor systems and breaks
suspend.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:52 -08:00
Ian Campbell
fa24ba62ea xen: correctly restore pfn_to_mfn_list_list after resume
pvops kernels >= 2.6.30 can currently only be saved and restored once. The
second attempt to save results in:

    ERROR Internal error: Frame# in pfn-to-mfn frame list is not in pseudophys
    ERROR Internal error: entry 0: p2m_frame_list[0] is 0xf2c2c2c2, max 0x120000
    ERROR Internal error: Failed to map/save the p2m frame list

I finally narrowed it down to:

    commit cdaead6b4e
        Author: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
        Date:   Fri Feb 27 15:34:59 2009 -0800

            xen: split construction of p2m mfn tables from registration

            Build the p2m_mfn_list_list early with the rest of the p2m table, but
            register it later when the real shared_info structure is in place.

            Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

The unforeseen side-effect of this change was to cause the mfn list list to not
be rebuilt on resume. Prior to this change it would have been rebuilt via
xen_post_suspend() -> xen_setup_shared_info() -> xen_setup_mfn_list_list().

Fix by explicitly calling xen_build_mfn_list_list() from xen_post_suspend().

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:51 -08:00
Jeremy Fitzhardinge
3905bb2aa7 xen: restore runstate_info even if !have_vcpu_info_placement
Even if have_vcpu_info_placement is not set, we still need to set up
the runstate area on each resumed vcpu.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:51 -08:00
Ian Campbell
be012920ec xen: re-register runstate area earlier on resume.
This is necessary to ensure the runstate area is available to
xen_sched_clock before any calls to printk which will require it in
order to provide a timestamp.

I chose to pull the xen_setup_runstate_info out of xen_time_init into
the caller in order to maintain parity with calling
xen_setup_runstate_info separately from calling xen_time_resume.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:50 -08:00
H. Peter Anvin
4763ed4d45 x86, mm: Clean up and simplify NX enablement
The 32- and 64-bit code used very different mechanisms for enabling
NX, but even the 32-bit code was enabling NX in head_32.S if it is
available.  Furthermore, we had a bewildering collection of tests for
the available of NX.

This patch:

a) merges the 32-bit set_nx() and the 64-bit check_efer() function
   into a single x86_configure_nx() function.  EFER control is left
   to the head code.

b) eliminates the nx_enabled variable entirely.  Things that need to
   test for NX enablement can verify __supported_pte_mask directly,
   and cpu_has_nx gives the supported status of NX.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Chris Wright <chrisw@sous-sol.org>
LKML-Reference: <1258154897-6770-5-git-send-email-hpa@zytor.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
2009-11-16 13:44:59 -08:00
Jeremy Fitzhardinge
1ccbf5344c xen: move Xen-testing predicates to common header
Move xen_domain and related tests out of asm-x86 to xen/xen.h so they
can be included whenever they are necessary.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 08:47:24 -08:00
Rusty Russell
d7d3756c5b cpumask: Use modern cpumask style in Xen
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
LKML-Reference: <200911031458.38406.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-04 13:19:50 +01:00
Jeremy Fitzhardinge
82d6469916 xen: mask extended topology info in cpuid
A Xen guest never needs to know about extended topology, and knowing
would just confuse it.

This patch just zeros ebx in leaf 0xb which indicates no topology info,
preventing a crash under Xen on cpus which support this leaf.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-11-03 11:09:12 -08:00
Tejun Heo
c6e22f9e3e percpu: make percpu symbols in xen unique
This patch updates percpu related symbols in xen such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* arch/x86/xen/smp.c, arch/x86/xen/time.c, arch/ia64/xen/irq_xen.c:
  add xen_ prefix to percpu variables

* arch/ia64/xen/time.c: add xen_ prefix to percpu variables, drop
  processed_ prefix and make them static

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
2009-10-29 22:34:13 +09:00
Jeremy Fitzhardinge
973df35ed9 xen: set up mmu_ops before trying to set any ptes
xen_setup_stackprotector() ends up trying to set page protections,
so we need to have vm_mmu_ops set up before trying to do so.
Failing to do so causes an early boot crash.

[ Impact: Fix early crash under Xen. ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-10-27 16:54:19 -07:00
Alexey Dobriyan
828c09509b const: constify remaining file_operations
[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Linus Torvalds
5bb241b325 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Remove redundant non-NUMA topology functions
  x86: early_printk: Protect against using the same device twice
  x86: Reduce verbosity of "PAT enabled" kernel message
  x86: Reduce verbosity of "TSC is reliable" message
  x86: mce: Use safer ways to access MCE registers
  x86: mce, inject: Use real inject-msg in raise_local
  x86: mce: Fix thermal throttling message storm
  x86: mce: Clean up thermal throttling state tracking code
  x86: split NX setup into separate file to limit unstack-protected code
  xen: check EFER for NX before setting up GDT mapping
  x86: Cleanup linker script using new linker script macros.
  x86: Use section .data.page_aligned for the idt_table.
  x86: convert to use __HEAD and HEAD_TEXT macros.
  x86: convert compressed loader to use __HEAD and HEAD_TEXT macros.
  x86: fix fragile computation of vsyscall address
2009-09-26 10:13:35 -07:00
Rusty Russell
78f1c4d6b0 cpumask: use mm_cpumask() wrapper: x86
Makes code futureproof against the impending change to mm->cpu_vm_mask (to be a pointer).

It's also a chance to use the new cpumask_ ops which take a pointer
(the older ones are deprecated, but there's no hurry for arch code).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-24 09:34:52 +09:30
Ingo Molnar
14c93e8eba Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen into x86/urgent 2009-09-23 14:35:10 +02:00
Jeremy Fitzhardinge
b75fe4e5b8 xen: check EFER for NX before setting up GDT mapping
x86-64 assumes NX is available by default, so we need to
explicitly check for it before using NX.  Some first-generation
Intel x86-64 processors didn't support NX, and even recent systems
allow it to be disabled in BIOS.

[ Impact: prevent Xen crash on NX-less 64-bit machines ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-09-21 13:49:43 -07:00
Linus Torvalds
78f28b7c55 Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (38 commits)
  x86: Move get/set_wallclock to x86_platform_ops
  x86: platform: Fix section annotations
  x86: apic namespace cleanup
  x86: Distangle ioapic and i8259
  x86: Add Moorestown early detection
  x86: Add hardware_subarch ID for Moorestown
  x86: Add early platform detection
  x86: Move tsc_init to late_time_init
  x86: Move tsc_calibration to x86_init_ops
  x86: Replace the now identical time_32/64.c by time.c
  x86: time_32/64.c unify profile_pc
  x86: Move calibrate_cpu to tsc.c
  x86: Make timer setup and global variables the same in time_32/64.c
  x86: Remove mca bus ifdef from timer interrupt
  x86: Simplify timer_ack magic in time_32.c
  x86: Prepare unification of time_32/64.c
  x86: Remove do_timer hook
  x86: Add timer_init to x86_init_ops
  x86: Move percpu clockevents setup to x86_init_ops
  x86: Move xen_post_allocator_init into xen_pagetable_setup_done
  ...

Fix up conflicts in arch/x86/include/asm/io_apic.h
2009-09-18 14:05:47 -07:00
Feng Tang
7bd867dfb4 x86: Move get/set_wallclock to x86_platform_ops
get/set_wallclock() have already a set of platform dependent
implementations (default, EFI, paravirt). MRST will add another
variant.

Moving them to platform ops simplifies the existing code and minimizes
the effort to integrate new variants.

Signed-off-by: Feng Tang <feng.tang@intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-09-16 14:34:50 +02:00
Linus Torvalds
b8cb48aae1 Merge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: split __phys_addr out into separate file
  xen: use stronger barrier after unlocking lock
  xen: only enable interrupts while actually blocking for spinlock
  xen: make -fstack-protector work under Xen
2009-09-14 10:23:49 -07:00
Linus Torvalds
c7208de304 Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits)
  x86: Fix code patching for paravirt-alternatives on 486
  x86, msr: change msr-reg.o to obj-y, and export its symbols
  x86: Use hard_smp_processor_id() to get apic id for AMD K8 cpus
  x86, sched: Workaround broken sched domain creation for AMD Magny-Cours
  x86, mcheck: Use correct cpumask for shared bank4
  x86, cacheinfo: Fixup L3 cache information for AMD multi-node processors
  x86: Fix CPU llc_shared_map information for AMD Magny-Cours
  x86, msr: Fix msr-reg.S compilation with gas 2.16.1, on 32-bit too
  x86: Move kernel_fpu_using to irq_fpu_usable in asm/i387.h
  x86, msr: fix msr-reg.S compilation with gas 2.16.1
  x86, msr: Export the register-setting MSR functions via /dev/*/msr
  x86, msr: Create _on_cpu helpers for {rw,wr}msr_safe_regs()
  x86, msr: Have the _safe MSR functions return -EIO, not -EFAULT
  x86, msr: CFI annotations, cleanups for msr-reg.S
  x86, asm: Make _ASM_EXTABLE() usable from assembly code
  x86, asm: Add 32-bit versions of the combined CFI macros
  x86, AMD: Disable wrongly set X86_FEATURE_LAHF_LM CPUID bit
  x86, msr: Rewrite AMD rd/wrmsr variants
  x86, msr: Add rd/wrmsr interfaces with preset registers
  x86: add specific support for Intel Atom architecture
  ...
2009-09-14 07:57:32 -07:00
Yang Xiaowei
2496afbf1e xen: use stronger barrier after unlocking lock
We need to have a stronger barrier between releasing the lock and
checking for any waiting spinners.  A compiler barrier is not sufficient
because the CPU's ordering rules do not prevent the read xl->spinners
from happening before the unlock assignment, as they are different
memory locations.

We need to have an explicit barrier to enforce the write-read ordering
to different memory locations.

Because of it, I can't bring up > 4 HVM guests on one SMP machine.

[ Code and commit comments expanded -J ]

[ Impact: avoid deadlock when using Xen PV spinlocks ]

Signed-off-by: Yang Xiaowei <xiaowei.yang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-09-09 16:38:44 -07:00
Jeremy Fitzhardinge
4d576b57b5 xen: only enable interrupts while actually blocking for spinlock
Where possible we enable interrupts while waiting for a spinlock to
become free, in order to reduce big latency spikes in interrupt handling.

However, at present if we manage to pick up the spinlock just before
blocking, we'll end up holding the lock with interrupts enabled for a
while.  This will cause a deadlock if we recieve an interrupt in that
window, and the interrupt handler tries to take the lock too.

Solve this by shrinking the interrupt-enabled region to just around the
blocking call.

[ Impact: avoid race/deadlock when using Xen PV spinlocks ]

Reported-by: "Yang, Xiaowei" <xiaowei.yang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-09-09 16:38:11 -07:00
Jeremy Fitzhardinge
577eebeae3 xen: make -fstack-protector work under Xen
-fstack-protector uses a special per-cpu "stack canary" value.
gcc generates special code in each function to test the canary to make
sure that the function's stack hasn't been overrun.

On x86-64, this is simply an offset of %gs, which is the usual per-cpu
base segment register, so setting it up simply requires loading %gs's
base as normal.

On i386, the stack protector segment is %gs (rather than the usual kernel
percpu %fs segment register).  This requires setting up the full kernel
GDT and then loading %gs accordingly.  We also need to make sure %gs is
initialized when bringing up secondary cpus too.

To keep things consistent, we do the full GDT/segment register setup on
both architectures.

Because we need to avoid -fstack-protected code before setting up the GDT
and because there's no way to disable it on a per-function basis, several
files need to have stack-protector inhibited.

[ Impact: allow Xen booting with stack-protector enabled ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-09-09 16:37:39 -07:00
H. Peter Anvin
0cc0213e73 x86, msr: Have the _safe MSR functions return -EIO, not -EFAULT
For some reason, the _safe MSR functions returned -EFAULT, not -EIO.
However, the only user which cares about the return code as anything
other than a boolean is the MSR driver, which wants -EIO.  Change it
to -EIO across the board.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-08-31 15:15:23 -07:00
Thomas Gleixner
2d826404f0 x86: Move tsc_calibration to x86_init_ops
TSC calibration is modified by the vmware hypervisor and paravirt by
separate means. Moorestown wants to add its own calibration routine as
well. So make calibrate_tsc a proper x86_init_ops function and
override it by paravirt or by the early setup of the vmware
hypervisor.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:47 +02:00
Thomas Gleixner
845b3944bb x86: Add timer_init to x86_init_ops
The timer init code is convoluted with several quirks and the paravirt
timer chooser. Figuring out which code path is actually taken is not
for the faint hearted.

Move the numaq TSC quirk to tsc_pre_init x86_init_ops function and
replace the paravirt time chooser and the remaining x86 quirk with a
simple x86_init_ops function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
736decac64 x86: Move percpu clockevents setup to x86_init_ops
paravirt overrides the setup of the default apic timers as per cpu
timers. Moorestown needs to override that as well.

Move it to x86_init_ops setup and create a separate x86_cpuinit struct
which holds the function for the secondary evtl. hotplugabble CPUs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
f1d7062a23 x86: Move xen_post_allocator_init into xen_pagetable_setup_done
We really do not need two paravirt/x86_init_ops functions which are
called in two consecutive source lines. Move the only user of
post_allocator_init into the already existing pagetable_setup_done
function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
030cb6c00d x86: Move paravirt pagetable_setup to x86_init_ops
Replace more paravirt hackery by proper x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
6f30c1ac3f x86: Move paravirt banner printout to x86_init_ops
Replace another obscure paravirt magic and move it to
x86_init_ops. Such a hook is also useful for embedded and special
hardware.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
42bbdb43b1 x86: Replace ARCH_SETUP by a proper x86_init_ops
ARCH_SETUP is a horrible leftover from the old arch/i386 mach support
code. It still has a lonely user in xen. Move it to x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
66bcaf0bde x86: Move irq_init to x86_init_ops
irq_init is overridden by x86_quirks and by paravirts. Unify the whole
mess and make it an unconditional x86_init_ops function which defaults
to the standard function and can be overridden by the early platform
code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
6b18ae3e2f x86: Move memory_setup to x86_init_ops
memory_setup is overridden by x86_quirks and by paravirts with weak
functions and quirks. Unify the whole mess and make it an
unconditional x86_init_ops function which defaults to the standard
function and can be overridden by the early platform code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
H. Peter Anvin
7adb4df410 x86, xen: Initialize cx to suppress warning
Initialize cx before calling xen_cpuid(), in order to suppress the
"may be used uninitialized in this function" warning.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2009-08-25 21:10:32 -07:00
Jeremy Fitzhardinge
d560bc6157 x86, xen: Suppress WP test on Xen
Xen always runs on CPUs which properly support WP enforcement in
privileged mode, so there's no need to test for it.

This also works around a crash reported by Arnd Hannemann, though I
think its just a band-aid for that case.

Reported-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-25 21:10:32 -07:00
Ingo Molnar
cbcb340cb6 Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen into x86/urgent 2009-08-20 12:05:24 +02:00
Jeremy Fitzhardinge
ce2eef33d3 xen: rearrange things to fix stackprotector
Make sure the stack-protector segment registers are properly set up
before calling any functions which may have stack-protection compiled
into them.

[ Impact: prevent Xen early-boot crash when stack-protector is enabled ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-08-19 17:09:28 -07:00
Linus Torvalds
be15f9d63b Merge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (42 commits)
  xen: cache cr0 value to avoid trap'n'emulate for read_cr0
  xen/x86-64: clean up warnings about IST-using traps
  xen/x86-64: fix breakpoints and hardware watchpoints
  xen: reserve Xen start_info rather than e820 reserving
  xen: add FIX_TEXT_POKE to fixmap
  lguest: update lazy mmu changes to match lguest's use of kvm hypercalls
  xen: honour VCPU availability on boot
  xen: add "capabilities" file
  xen: drop kexec bits from /sys/hypervisor since kexec isn't implemented yet
  xen/sys/hypervisor: change writable_pt to features
  xen: add /sys/hypervisor support
  xen/xenbus: export xenbus_dev_changed
  xen: use device model for suspending xenbus devices
  xen: remove suspend_cancel hook
  xen/dev-evtchn: clean up locking in evtchn
  xen: export ioctl headers to userspace
  xen: add /dev/xen/evtchn driver
  xen: add irq_from_evtchn
  xen: clean up gate trap/interrupt constants
  xen: set _PAGE_NX in __supported_pte_mask before pagetable construction
  ...
2009-06-10 16:16:27 -07:00
Jeremy Fitzhardinge
b4ecc12699 x86: Fix performance regression caused by paravirt_ops on native kernels
Xiaohui Xin and some other folks at Intel have been looking into what's
behind the performance hit of paravirt_ops when running native.

It appears that the hit is entirely due to the paravirtualized
spinlocks introduced by:

 | commit 8efcbab674
 | Date:   Mon Jul 7 12:07:51 2008 -0700
 |
 |     paravirt: introduce a "lock-byte" spinlock implementation

The extra call/return in the spinlock path is somehow
causing an increase in the cycles/instruction of somewhere around 2-7%
(seems to vary quite a lot from test to test).  The working theory is
that the CPU's pipeline is getting upset about the
call->call->locked-op->return->return, and seems to be failing to
speculate (though I haven't seen anything definitive about the precise
reasons).  This doesn't entirely make sense, because the performance
hit is also visible on unlock and other operations which don't involve
locked instructions.  But spinlock operations clearly swamp all the
other pvops operations, even though I can't imagine that they're
nearly as common (there's only a .05% increase in instructions
executed).

If I disable just the pv-spinlock calls, my tests show that pvops is
identical to non-pvops performance on native (my measurements show that
it is actually about .1% faster, but Xiaohui shows a .05% slowdown).

Summary of results, averaging 10 runs of the "mmperf" test, using a
no-pvops build as baseline:

		nopv		Pv-nospin	Pv-spin
CPU cycles	100.00%		99.89%		102.18%
instructions	100.00%		100.10%		100.15%
CPI		100.00%		99.79%		102.03%
cache ref	100.00%		100.84%		100.28%
cache miss	100.00%		90.47%		88.56%
cache miss rate	100.00%		89.72%		88.31%
branches	100.00%		99.93%		100.04%
branch miss	100.00%		103.66%		107.72%
branch miss rt	100.00%		103.73%		107.67%
wallclock	100.00%		99.90%		102.20%

The clear effect here is that the 2% increase in CPI is
directly reflected in the final wallclock time.

(The other interesting effect is that the more ops are
out of line calls via pvops, the lower the cache access
and miss rates.  Not too surprising, but it suggests that
the non-pvops kernel is over-inlined.  On the flipside,
the branch misses go up correspondingly...)

So, what's the fix?

Paravirt patching turns all the pvops calls into direct calls, so
_spin_lock etc do end up having direct calls.  For example, the compiler
generated code for paravirtualized _spin_lock is:

<_spin_lock+0>:		mov    %gs:0xb4c8,%rax
<_spin_lock+9>:		incl   0xffffffffffffe044(%rax)
<_spin_lock+15>:	callq  *0xffffffff805a5b30
<_spin_lock+22>:	retq

The indirect call will get patched to:
<_spin_lock+0>:		mov    %gs:0xb4c8,%rax
<_spin_lock+9>:		incl   0xffffffffffffe044(%rax)
<_spin_lock+15>:	callq <__ticket_spin_lock>
<_spin_lock+20>:	nop; nop		/* or whatever 2-byte nop */
<_spin_lock+22>:	retq

One possibility is to inline _spin_lock, etc, when building an
optimised kernel (ie, when there's no spinlock/preempt
instrumentation/debugging enabled).  That will remove the outer
call/return pair, returning the instruction stream to a single
call/return, which will presumably execute the same as the non-pvops
case.  The downsides arel 1) it will replicate the
preempt_disable/enable code at eack lock/unlock callsite; this code is
fairly small, but not nothing; and 2) the spinlock definitions are
already a very heavily tangled mass of #ifdefs and other preprocessor
magic, and making any changes will be non-trivial.

The other obvious answer is to disable pv-spinlocks.  Making them a
separate config option is fairly easy, and it would be trivial to
enable them only when Xen is enabled (as the only non-default user).
But it doesn't really address the common case of a distro build which
is going to have Xen support enabled, and leaves the open question of
whether the native performance cost of pv-spinlocks is worth the
performance improvement on a loaded Xen system (10% saving of overall
system CPU when guests block rather than spin).  Still it is a
reasonable short-term workaround.

[ Impact: fix pvops performance regression when running native ]

Analysed-by: "Xin Xiaohui" <xiaohui.xin@intel.com>
Analysed-by: "Li Xin" <xin.li@intel.com>
Analysed-by: "Nakajima Jun" <jun.nakajima@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Xen-devel <xen-devel@lists.xensource.com>
LKML-Reference: <4A0B62F7.5030802@goop.org>
[ fixed the help text ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-15 20:07:42 +02:00