17764 Commits

Author SHA1 Message Date
H. Peter Anvin
3979fdce77 * Avoid confusing the user by returning -EIO instead of -ENOENT in
efivarfs if an EFI variable gets deleted from under us and return EOF
    when reading from a zero-length file - Lingzhu Xiang
 
  * Fix an oops in efivar_update_sysfs_entries() caused by reusing (and
    therefore corrupting) a kzalloc() allocation - Seiji Aguchi
 
  * Initialise the DataSize argument to GetVariable() otherwise it will
    not be updated with the actual size of the variable on return.
    Discovered on a Acer Aspire V3 BIOS - Lee, Chun-Yi
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Merge tag 'efi-urgent' into x86/urgent

 * Avoid confusing the user by returning -EIO instead of -ENOENT in
   efivarfs if an EFI variable gets deleted from under us and return EOF
   when reading from a zero-length file - Lingzhu Xiang

 * Fix an oops in efivar_update_sysfs_entries() caused by reusing (and
   therefore corrupting) a kzalloc() allocation - Seiji Aguchi

 * Initialise the DataSize argument to GetVariable() otherwise it will
   not be updated with the actual size of the variable on return.
   Discovered on a Acer Aspire V3 BIOS - Lee, Chun-Yi

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-05-22 10:58:57 -07:00
Avi Kivity
e47a5f5fb7 KVM: x86 emulator: convert XADD to fastop
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:24 +03:00
Avi Kivity
203831e8e4 KVM: x86 emulator: drop unused old-style inline emulation
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:23 +03:00
Avi Kivity
b8c0b6ae49 KVM: x86 emulator: convert DIV/IDIV to fastop
Since DIV and IDIV can generate exceptions, we need an additional output
parameter indicating whether an execption has occured.  To avoid increasing
register pressure on i386, we use %rsi, which is already allocated for
the fastop code pointer.

Gleb: added comment about fop usage as exception indication.

Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:21 +03:00
Avi Kivity
b9fa409b00 KVM: x86 emulator: convert single-operand MUL/IMUL to fastop
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:20 +03:00
Avi Kivity
017da7b604 KVM: x86 emulator: Switch fastop src operand to RDX
This makes OpAccHi useful.

Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:19 +03:00
Avi Kivity
ab2c5ce666 KVM: x86 emulator: switch MUL/DIV to DstXacc
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:17 +03:00
Avi Kivity
820207c8fc KVM: x86 emulator: decode extended accumulator explicity
Single-operand MUL and DIV access an extended accumulator: AX for byte
instructions, and DX:AX, EDX:EAX, or RDX:RAX for larger-sized instructions.
Add support for fetching the extended accumulator.

In order not to change things too much, RDX is loaded into Src2, which is
already loaded by fastop().  This avoids increasing register pressure on
i386.

Gleb: disable src writeback for ByteOp div/mul.

Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:16 +03:00
Avi Kivity
fb32b1eda2 KVM: x86 emulator: add support for writing back the source operand
Some instructions write back the source operand, not just the destination.
Add support for doing this via the decode flags.

Gleb: add BUG_ON() to prevent source to be memory operand.

Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21 15:43:14 +03:00
Linus Torvalds
5e427ec2d0 x86: Fix bit corruption at CPU resume time
In commit 78d77df71510 ("x86-64, init: Do not set NX bits on non-NX
capable hardware") we added the early_pmd_flags that gets the NX bit set
when a CPU supports NX. However, the new variable was marked __initdata,
because the main _use_ of this is in an __init routine.

However, the bit setting happens from secondary_startup_64(), which is
called not only at bootup, but on every secondary CPU start.  Including
resuming from STR and at CPU hotplug time.  So the value cannot be
__initdata.

Reported-bisected-and-tested-by: Michal Hocko <mhocko@suse.cz>
Cc: stable@vger.kernel.org # v3.9
Acked-by: Peter Anvin <hpa@linux.intel.com>
Cc: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-20 11:36:03 -07:00
Bjorn Helgaas
f3f011750a Revert "x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0"
This reverts commit dd72be99d11dbf738d910a38479ce414a51eb21e.

Andy Shevchenko <andy.shevchenko@gmail.com> reported that this commit
broke Intel Medfield devices.

Reference: https://lkml.kernel.org/r/CAHp75Vdf6gFZChS47=grUygHBDWcoOWDYPzw+Zj5bdVCWj85Jw@mail.gmail.com
Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-05-20 10:20:21 -06:00
Tim Chen
31d939625a crypto: crct10dif - Accelerated CRC T10 DIF computation with PCLMULQDQ instruction
This is the x86_64 CRC T10 DIF transform accelerated with the PCLMULQDQ
instructions.  Details discussing the implementation can be found in the
paper:

"Fast CRC Computation for Generic Polynomials Using PCLMULQDQ Instruction"
http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-05-20 20:11:06 +08:00
Eric Dumazet
314beb9bca x86: bpf_jit_comp: secure bpf jit against spraying attacks
hpa bringed into my attention some security related issues
with BPF JIT on x86.

This patch makes sure the bpf generated code is marked read only,
as other kernel text sections.

It also splits the unused space (we vmalloc() and only use a fraction of
the page) in two parts, so that the generated bpf code not starts at a
known offset in the page, but a pseudo random one.

Refs:
http://mainisusuallyafunction.blogspot.com/2012/11/attacking-hardened-linux-systems-with.html

Reported-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-19 23:55:41 -07:00
Daniel Baluta
6865b32a86 lguest: rename i386_head.S
Since commit 9a163ed8e0 (i386: move kernel) kernel/i386_head.S
was renamed to kernel/head_32.S. We do the same for lguest/i386_head.S.

Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-05-20 12:09:40 +09:30
Marc Zyngier
535cf7b3b1 KVM: get rid of $(addprefix ../../../virt/kvm/, ...) in Makefiles
As requested by the KVM maintainers, remove the addprefix used to
refer to the main KVM code from the arch code, and replace it with
a KVM variable that does the same thing.

Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Christoffer Dall <cdall@cs.columbia.edu>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-19 15:14:00 +03:00
Eric Dumazet
650c849670 x86: bpf_jit_comp: can call module_free() from any context
It looks like we can call module_free()/vfree() from softirq context,
so no longer need a wrapper and a work_struct.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-17 17:37:19 -07:00
Gleb Natapov
35af577aac KVM: MMU: clenaup locking in mmu_free_roots()
Do locking around each case separately instead of having one lock and two
unlocks. Move root_hpa assignment out of the lock.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-16 11:55:51 +03:00
Linus Torvalds
ae3b29e67c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:

 - Fix for a CPU hot-add deadlock in microcode update code

 - Fix for idle consolidation fallout

 - Documentation update for initial kernel direct mapping

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Add missing comments for initial kernel direct mapping
  x86/microcode: Add local mutex to fix physical CPU hot-add deadlock
  x86: Fix idle consolidation fallout
2013-05-15 14:07:53 -07:00
Linus Torvalds
cc51bf6e6d Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:

 - Cure for not using zalloc in the first place, which leads to random
   crashes with CPUMASK_OFF_STACK.

 - Revert a user space visible change which broke udev

 - Add a missing cpu_online early return introduced by the new full
   dyntick conversions

 - Plug a long standing race in the timer wheel cpu hotplug code.
   Sigh...

 - Cleanup NOHZ per cpu data on cpu down to prevent stale data on cpu
   up.

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons
  timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE
  tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offline
  tick: Cleanup NOHZ per cpu data on cpu down
  tick: Use zalloc_cpumask_var for allocating offstack cpumasks
2013-05-15 14:05:17 -07:00
Marcelo Tosatti
0061d53daf KVM: x86: limit difference between kvmclock updates
kvmclock updates which are isolated to a given vcpu, such as vcpu->cpu
migration, should not allow system_timestamp from the rest of the vcpus
to remain static. Otherwise ntp frequency correction applies to one
vcpu's system_timestamp but not the others.

So in those cases, request a kvmclock update for all vcpus. The worst
case for a remote vcpu to update its kvmclock is then bounded by maximum
nohz sleep latency.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-15 20:36:09 +03:00
John Stultz
b4f711ee03 time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons
Kay Sievers noted that the ALWAYS_USE_PERSISTENT_CLOCK config,
which enables some minor compile time optimization to avoid
uncessary code in mostly the suspend/resume path could cause
problems for userland.

In particular, the dependency for RTC_HCTOSYS on
!ALWAYS_USE_PERSISTENT_CLOCK, which avoids setting the time
twice and simplifies suspend/resume, has the side effect
of causing the /sys/class/rtc/rtcN/hctosys flag to always be
zero, and this flag is commonly used by udev to setup the
/dev/rtc symlink to /dev/rtcN, which can cause pain for
older applications.

While the udev rules could use some work to be less fragile,
breaking userland should strongly be avoided. Additionally
the compile time optimizations are fairly minor, and the code
being optimized is likely to be reworked in the future, so
lets revert this change.

Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: stable <stable@vger.kernel.org> #3.9
Cc: Feng Tang <feng.tang@intel.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Link: http://lkml.kernel.org/r/1366828376-18124-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14 20:54:06 +02:00
Jan Kiszka
f1ed0450a5 KVM: x86: Remove support for reporting coalesced APIC IRQs
Since the arrival of posted interrupt support we can no longer guarantee
that coalesced IRQs are always reported to the IRQ source. Moreover,
accumulated APIC timer events could cause a busy loop when a VCPU should
rather be halted. The consensus is to remove coalesced tracking from the
LAPIC.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-14 12:09:02 +03:00
Lee, Chun-Yi
eccaf52fee x86, efi: initial the local variable of DataSize to zero
That will be better initial the value of DataSize to zero for the input of
GetVariable(), otherwise we will feed a random value. The debug log of input
DataSize like this:

...
[  195.915612] EFI Variables Facility v0.08 2004-May-17
[  195.915819] efi: size: 18446744071581821342
[  195.915969] efi:  size': 18446744071581821342
[  195.916324] efi: size: 18446612150714306560
[  195.916632] efi:  size': 18446612150714306560
[  195.917159] efi: size: 18446612150714306560
[  195.917453] efi:  size': 18446612150714306560
...

The size' is value that was returned by BIOS.

After applied this patch:
[   82.442042] EFI Variables Facility v0.08 2004-May-17
[   82.442202] efi: size: 0
[   82.442360] efi:  size': 1039
[   82.443828] efi: size: 0
[   82.444127] efi:  size': 2616
[   82.447057] efi: size: 0
[   82.447356] efi:  size': 5832
...

Found on Acer Aspire V3 BIOS, it will not return the size of data if we input a
non-zero DataSize.

Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-05-14 08:13:05 +01:00
Borislav Petkov
4d067d8e05 x86: Extend #DF debugging aid to 64-bit
It is sometimes very helpful to be able to pinpoint the location which
causes a double fault before it turns into a triple fault and the
machine reboots. We have this for 32-bit already so extend it to 64-bit.
On 64-bit we get the register snapshot at #DF time and not from the
first exception which actually causes the #DF. It should be close
enough, though.

[ hpa: and definitely better than nothing, which is what we have now. ]

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1368093749-31296-1-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-05-13 13:42:44 -07:00
Takuya Yoshikawa
e2858b4ab1 KVM: MMU: Use kvm_mmu_sync_roots() in kvm_mmu_load()
No need to open-code this function.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-12 14:52:55 +03:00
Linus Torvalds
607eeb0b83 Bug-fixes:
- More fixes in the vCPU PVHVM hotplug path.
  - Add more documentation.
  - Fix various ARM related issues in the Xen generic drivers.
  - Updates in the xen-pciback driver per Bjorn's updates.
  - Mask the x2APIC feature for PV guests.
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Merge tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 - More fixes in the vCPU PVHVM hotplug path.
 - Add more documentation.
 - Fix various ARM related issues in the Xen generic drivers.
 - Updates in the xen-pciback driver per Bjorn's updates.
 - Mask the x2APIC feature for PV guests.

* tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/pci: Used cached MSI-X capability offset
  xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
  xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
  xen: mask x2APIC feature in PV
  xen: SWIOTLB is only used on x86
  xen/spinlock: Fix check from greater than to be also be greater or equal to.
  xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info
  xen/vcpu: Document the xen_vcpu_info and xen_vcpu
  xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
2013-05-11 16:19:30 -07:00
Linus Torvalds
ac4e01093f Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Pull idle update from Len Brown:
 "Add support for new Haswell-ULT CPU idle power states"

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  intel_idle: initial C8, C9, C10 support
  tools/power turbostat: display C8, C9, C10 residency
2013-05-11 15:23:17 -07:00
Linus Torvalds
3644bc2ec7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull stray syscall bits from Al Viro:
 "Several syscall-related commits that were missing from the original"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  switch compat_sys_sysctl to COMPAT_SYSCALL_DEFINE
  unicore32: just use mmap_pgoff()...
  unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE
  x86, vm86: fix VM86 syscalls: use SYSCALL_DEFINEx(...)
2013-05-10 09:21:05 -07:00
Linus Torvalds
c67723ebbb Merge tag 'kvm-3.10-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Gleb Natapov:
 "Most of the fixes are in the emulator since now we emulate more than
  we did before for correctness sake we see more bugs there, but there
  is also an OOPS fixed and corruption of xcr0 register."

* tag 'kvm-3.10-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: emulator: emulate SALC
  KVM: emulator: emulate XLAT
  KVM: emulator: emulate AAM
  KVM: VMX: fix halt emulation while emulating invalid guest sate
  KVM: Fix kvm_irqfd_init initialization
  KVM: x86: fix maintenance of guest/host xcr0 state
2013-05-10 09:08:21 -07:00
Bjorn Helgaas
7c86617dde xen/pci: Used cached MSI-X capability offset
We now cache the MSI-X capability offset in the struct pci_dev, so no
need to find the capability again.

Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-10 09:10:38 -04:00
Bjorn Helgaas
4be6bfe2af xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
PCI_MSIX_FLAGS_BIRMASK is mis-named because the BIR mask is in the
Table Offset register, not the flags ("Message Control" per spec)
register.

Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-10 09:10:20 -04:00
Zhang Yanfei
cf8b166d5c x86/mm: Add missing comments for initial kernel direct mapping
Two sets of comments were lost during patch-series shuffling:

  - comments for init_range_memory_mapping()

  - comments in init_mem_mapping that is helpful for reminding people
    that the pagetable is setup top-down

The comments were written by Yinghai in his patch in:

   https://lkml.org/lkml/2012/11/28/620

This patch reintroduces them.

Originally-From: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/518BC776.7010506@gmail.com
[ Tidied it all up a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-10 12:00:35 +02:00
Al Viro
91c2e0bcae unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-09 13:46:38 -04:00
Linus Torvalds
e15e611906 PCI updates for v3.10:
MSI
       PCI: Set ->mask_pos correctly
   Hotplug
       PCI: Delay final fixups until resources are assigned
   Moorestown
       x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0
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Merge tag 'pci-v3.10-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "MSI:
      PCI: Set ->mask_pos correctly
  Hotplug:
      PCI: Delay final fixups until resources are assigned
  Moorestown:
      x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0"

* tag 'pci-v3.10-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: Delay final fixups until resources are assigned
  x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0
  PCI: Set ->mask_pos correctly
2013-05-09 10:21:44 -07:00
Linus Torvalds
5647ac0ad4 Removal of GENERIC_GPIO for v3.10
GENERIC_GPIO now synonymous with GPIOLIB. There are no longer any valid
 cases for enableing GENERIC_GPIO without GPIOLIB, even though it is
 possible to do so which has been causing confusion and breakage. This
 branch does the work to completely eliminate GENERIC_GPIO.
 
 However, it is not trivial to just create a branch to remove it. Over
 the course of the v3.9 cycle more code referencing GENERIC_GPIO has been
 added to linux-next that conflicts with this branch. The following must
 be done to resolve the conflicts when merging this branch into mainline:
 
 * "git grep CONFIG_GENERIC_GPIO" should return 0 hits. Matches should be
   replaced with CONFIG_GPIOLIB
 * "git grep '\bGENERIC_GPIO\b'" should return 1 hit in the Chinese
   documentation.
 * Selectors of GENERIC_GPIO should be turned into selectors of GPIOLIB
 * definitions of the option in architecture Kconfig code should be deleted.
 
 Stephen has 3 merge fixup patches[1] that do the above. They are currently
 applicable on mainline as of May 2nd.
 
 [1] http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg428056.html
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux

Pull removal of GENERIC_GPIO from Grant Likely:
 "GENERIC_GPIO now synonymous with GPIOLIB.  There are no longer any
  valid cases for enableing GENERIC_GPIO without GPIOLIB, even though it
  is possible to do so which has been causing confusion and breakage.
  This branch does the work to completely eliminate GENERIC_GPIO."

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux:
  gpio: update gpio Chinese documentation
  Remove GENERIC_GPIO config option
  Convert selectors of GENERIC_GPIO to GPIOLIB
  blackfin: force use of gpiolib
  m68k: coldfire: use gpiolib
  mips: pnx833x: remove requirement for GENERIC_GPIO
  openrisc: default GENERIC_GPIO to false
  avr32: default GENERIC_GPIO to false
  xtensa: remove explicit selection of GENERIC_GPIO
  sh: replace CONFIG_GENERIC_GPIO by CONFIG_GPIOLIB
  powerpc: remove redundant GENERIC_GPIO selection
  unicore32: default GENERIC_GPIO to false
  unicore32: remove unneeded select GENERIC_GPIO
  arm: plat-orion: use GPIO driver on CONFIG_GPIOLIB
  arm: remove redundant GENERIC_GPIO selection
  mips: alchemy: require gpiolib
  mips: txx9: change GENERIC_GPIO to GPIOLIB
  mips: loongson: use GPIO driver on CONFIG_GPIOLIB
  mips: remove redundant GENERIC_GPIO select
2013-05-09 09:59:16 -07:00
Paolo Bonzini
326f578f7e KVM: emulator: emulate SALC
This is an almost-undocumented instruction available in 32-bit mode.
I say "almost" undocumented because AMD documents it in their opcode
maps just to say that it is unavailable in 64-bit mode (sections
"A.2.1 One-Byte Opcodes" and "B.3 Invalid and Reassigned Instructions
in 64-Bit Mode").

It is roughly equivalent to "sbb %al, %al" except it does not
set the flags.  Use fastop to emulate it, but do not use the opcode
directly because it would fail if the host is 64-bit!

Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09 13:15:08 +03:00
Paolo Bonzini
7fa57952d7 KVM: emulator: emulate XLAT
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
It is just a MOV in disguise, with a funny source address.

Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09 13:14:51 +03:00
Paolo Bonzini
a035d5c64d KVM: emulator: emulate AAM
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.

AAM needs the source operand to be unsigned; do the same in AAD as well
for consistency, even though it does not affect the result.

Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09 13:12:58 +03:00
Konrad Rzeszutek Wilk
074d72ff57 x86/microcode: Add local mutex to fix physical CPU hot-add deadlock
This can easily be triggered if a new CPU is added (via
ACPI hotplug mechanism) and from user-space you do:

   echo 1 > /sys/devices/system/cpu/cpu3/online

(or wait for UDEV to do it) on a newly appeared physical CPU.

The deadlock is that the "store_online" in drivers/base/cpu.c
takes the cpu_hotplug_driver_lock() lock, then calls "cpu_up".
"cpu_up" eventually ends up calling "save_mc_for_early"
which also takes the cpu_hotplug_driver_lock() lock.

And here is that lockdep thinks of it:

 smpboot: Stack at about ffff880075c39f44
 smpboot: CPU3: has booted.
 microcode: CPU3 sig=0x206a7, pf=0x2, revision=0x25

 =============================================
 [ INFO: possible recursive locking detected ]
 3.9.0upstream-10129-g167af0e #1 Not tainted
 ---------------------------------------------
 sh/2487 is trying to acquire lock:
  (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20

 but task is already holding lock:
  (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20

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

        CPU0
        ----
   lock(x86_cpu_hotplug_driver_mutex);
   lock(x86_cpu_hotplug_driver_mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 6 locks held by sh/2487:
  #0:  (sb_writers#5){.+.+.+}, at: [<ffffffff811ca48d>] vfs_write+0x17d/0x190
  #1:  (&buffer->mutex){+.+.+.}, at: [<ffffffff812464ef>] sysfs_write_file+0x3f/0x160
  #2:  (s_active#20){.+.+.+}, at: [<ffffffff81246578>] sysfs_write_file+0xc8/0x160
  #3:  (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
  #4:  (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff810961c2>] cpu_maps_update_begin+0x12/0x20
  #5:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff810962a7>] cpu_hotplug_begin+0x27/0x60

Suggested-and-Acked-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: fenghua.yu@intel.com
Cc: xen-devel@lists.xensource.com
Cc: stable@vger.kernel.org # for v3.9
Link: http://lkml.kernel.org/r/1368029583-23337-1-git-send-email-konrad.wilk@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-09 11:10:00 +02:00
Gleb Natapov
8d76c49e9f KVM: VMX: fix halt emulation while emulating invalid guest sate
The invalid guest state emulation loop does not check halt_request
which causes 100% cpu loop while guest is in halt and in invalid
state, but more serious issue is that this leaves halt_request set, so
random instruction emulated by vm86 #GP exit can be interpreted
as halt which causes guest hang. Fix both problems by handling
halt_request in emulation loop.

Reported-by: Tomas Papan <tomas.papan@gmail.com>
Tested-by: Tomas Papan <tomas.papan@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
CC: stable@vger.kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09 09:04:56 +03:00
Zhenzhong Duan
4ea9b9aca9 xen: mask x2APIC feature in PV
On x2apic enabled pvm, doing sysrq+l, got NULL pointer dereference as below.

    SysRq : Show backtrace of all active CPUs
    BUG: unable to handle kernel NULL pointer dereference at           (null)
    IP: [<ffffffff8125e3cb>] memcpy+0xb/0x120
    Call Trace:
     [<ffffffff81039633>] ? __x2apic_send_IPI_mask+0x73/0x160
     [<ffffffff8103973e>] x2apic_send_IPI_all+0x1e/0x20
     [<ffffffff8103498c>] arch_trigger_all_cpu_backtrace+0x6c/0xb0
     [<ffffffff81501be4>] ? _raw_spin_lock_irqsave+0x34/0x50
     [<ffffffff8131654e>] sysrq_handle_showallcpus+0xe/0x10
     [<ffffffff8131616d>] __handle_sysrq+0x7d/0x140
     [<ffffffff81316230>] ? __handle_sysrq+0x140/0x140
     [<ffffffff81316287>] write_sysrq_trigger+0x57/0x60
     [<ffffffff811ca996>] proc_reg_write+0x86/0xc0
     [<ffffffff8116dd8e>] vfs_write+0xce/0x190
     [<ffffffff8116e3e5>] sys_write+0x55/0x90
     [<ffffffff8150a242>] system_call_fastpath+0x16/0x1b

That's because apic points to apic_x2apic_cluster or apic_x2apic_phys
but the basic element like cpumask isn't initialized.

Mask x2APIC feature in pvm to avoid overwrite of apic pointer,
update commit message per Konrad's suggestion.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Tested-by: Tamon Shiose <tamon.shiose@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-08 08:38:11 -04:00
Konrad Rzeszutek Wilk
cb91f8f44c xen/spinlock: Fix check from greater than to be also be greater or equal to.
During review of git commit cb9c6f15f318aa3aeb62fe525aa5c6dcf6eee159
("xen/spinlock:  Check against default value of -1 for IRQ line.")
Stefano pointed out a bug in the patch. Unfortunatly due to vacation
timing the fix was not applied and this patch fixes it up.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-08 08:38:09 -04:00
Konrad Rzeszutek Wilk
d5b17dbff8 xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info
As it will point to some data, but not event channel data (the
shared_info has an array limited to 32).

This means that for PVHVM guests with more than 32 VCPUs without
the usage of VCPUOP_register_info any interrupts to VCPUs
larger than 32 would have gone unnoticed during early bootup.

That is OK, as during early bootup, in smp_init we end up calling
the hotplug mechanism (xen_hvm_cpu_notify) which makes the
VCPUOP_register_vcpu_info call for all VCPUs and we can receive
interrupts on VCPUs 33 and further.

This is just a cleanup.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-08 08:38:08 -04:00
Marcelo Tosatti
42bdf991f4 KVM: x86: fix maintenance of guest/host xcr0 state
Emulation of xcr0 writes zero guest_xcr0_loaded variable so that
subsequent VM-entry reloads CPU's xcr0 with guests xcr0 value.

However, this is incorrect because guest_xcr0_loaded variable is
read to decide whether to reload hosts xcr0.

In case the vcpu thread is scheduled out after the guest_xcr0_loaded = 0
assignment, and scheduler decides to preload FPU:

switch_to
{
  __switch_to
    __math_state_restore
      restore_fpu_checking
        fpu_restore_checking
          if (use_xsave())
              fpu_xrstor_checking
		xrstor64 with CPU's xcr0 == guests xcr0

Fix by properly restoring hosts xcr0 during emulation of xcr0 writes.

Analyzed-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-08 12:47:43 +03:00
Linus Torvalds
c8de2fa4dc Merge branch 'rwsem-optimizations'
Merge rwsem optimizations from Michel Lespinasse:
 "These patches extend Alex Shi's work (which added write lock stealing
  on the rwsem slow path) in order to provide rwsem write lock stealing
  on the fast path (that is, without taking the rwsem's wait_lock).

  I have unfortunately been unable to push this through -next before due
  to Ingo Molnar / David Howells / Peter Zijlstra being busy with other
  things.  However, this has gotten some attention from Rik van Riel and
  Davidlohr Bueso who both commented that they felt this was ready for
  v3.10, and Ingo Molnar has said that he was OK with me pushing
  directly to you.  So, here goes :)

  Davidlohr got the following test results from pgbench running on a
  quad-core laptop:

    | db_size | clients  |  tps-vanilla   |   tps-rwsem  |
    +---------+----------+----------------+--------------+
    | 160 MB   |       1 |           5803 |         6906 | + 19.0%
    | 160 MB   |       2 |          13092 |        15931 |
    | 160 MB   |       4 |          29412 |        33021 |
    | 160 MB   |       8 |          32448 |        34626 |
    | 160 MB   |      16 |          32758 |        33098 |
    | 160 MB   |      20 |          26940 |        31343 | + 16.3%
    | 160 MB   |      30 |          25147 |        28961 |
    | 160 MB   |      40 |          25484 |        26902 |
    | 160 MB   |      50 |          24528 |        25760 |
    ------------------------------------------------------
    | 1.6 GB   |       1 |           5733 |         7729 | + 34.8%
    | 1.6 GB   |       2 |           9411 |        19009 | + 101.9%
    | 1.6 GB   |       4 |          31818 |        33185 |
    | 1.6 GB   |       8 |          33700 |        34550 |
    | 1.6 GB   |      16 |          32751 |        33079 |
    | 1.6 GB   |      20 |          30919 |        31494 |
    | 1.6 GB   |      30 |          28540 |        28535 |
    | 1.6 GB   |      40 |          26380 |        27054 |
    | 1.6 GB   |      50 |          25241 |        25591 |
    ------------------------------------------------------
    | 7.6 GB   |       1 |           5779 |         6224 |
    | 7.6 GB   |       2 |          10897 |        13611 | + 24.9%
    | 7.6 GB   |       4 |          32683 |        33108 |
    | 7.6 GB   |       8 |          33968 |        34712 |
    | 7.6 GB   |      16 |          32287 |        32895 |
    | 7.6 GB   |      20 |          27770 |        31689 | + 14.1%
    | 7.6 GB   |      30 |          26739 |        29003 |
    | 7.6 GB   |      40 |          24901 |        26683 |
    | 7.6 GB   |      50 |          17115 |        25925 | + 51.5%
    ------------------------------------------------------

  (Davidlohr also has one additional patch which further improves
  throughput, though I will ask him to send it directly to you as I have
  suggested some minor changes)."

* emailed patches from Michel Lespinasse <walken@google.com>:
  rwsem: no need for explicit signed longs
  x86 rwsem: avoid taking slow path when stealing write lock
  rwsem: do not block readers at head of queue if other readers are active
  rwsem: implement support for write lock stealing on the fastpath
  rwsem: simplify __rwsem_do_wake
  rwsem: skip initial trylock in rwsem_down_write_failed
  rwsem: avoid taking wait_lock in rwsem_down_write_failed
  rwsem: use cmpxchg for trying to steal write lock
  rwsem: more agressive lock stealing in rwsem_down_write_failed
  rwsem: simplify rwsem_down_write_failed
  rwsem: simplify rwsem_down_read_failed
  rwsem: move rwsem_down_failed_common code into rwsem_down_{read,write}_failed
  rwsem: shorter spinlocked section in rwsem_down_failed_common()
  rwsem: make the waiter type an enumeration rather than a bitmask
2013-05-07 09:22:03 -07:00
Thomas Gleixner
97a5b81fa4 x86: Fix idle consolidation fallout
The core code expects the arch idle code to return with interrupts
enabled. The conversion missed two x86 cases which fail to do that.

Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305021557030.3972@ionos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-07 16:24:03 +02:00
Michel Lespinasse
a31a369b07 x86 rwsem: avoid taking slow path when stealing write lock
modify __down_write[_nested] and __down_write_trylock to grab the write
lock whenever the active count is 0, even if there are queued waiters
(they must be writers pending wakeup, since the active count is 0).

Note that this is an optimization only; architectures without this
optimization will still work fine:

- __down_write() would take the slow path which would take the wait_lock
  and then try stealing the lock (as in the spinlocked rwsem implementation)

- __down_write_trylock() would fail, but callers must be ready to deal
  with that - since there are some writers pending wakeup, they could
  have raced with us and obtained the lock before we steal it.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:17 -07:00
Konrad Rzeszutek Wilk
a520996ae2 xen/vcpu: Document the xen_vcpu_info and xen_vcpu
They are important structures and it is not clear at first
look what they are for.

The xen_vcpu is a pointer. By default it points to the shared_info
structure (at the CPU offset location). However if the
VCPUOP_register_vcpu_info hypercall is implemented we can make the
xen_vcpu pointer point to a per-CPU location.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v1: Added comments from Ian Campbell]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-07 10:05:34 -04:00
Linus Torvalds
99737982ca IOMMU Updates for Linux v3.10
The updates are mostly about the x86 IOMMUs this time. Exceptions are
 the groundwork for the PAMU IOMMU from Freescale (for a PPC platform)
 and an extension to the IOMMU group interface. On the x86 side this
 includes a workaround for VT-d to disable interrupt remapping on broken
 chipsets. On the AMD-Vi side the most important new feature is a kernel
 command-line interface to override broken information in IVRS ACPI
 tables and get interrupt remapping working this way. Besides that there
 are small fixes all over the place.
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Merge tag 'iommu-updates-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:
 "The updates are mostly about the x86 IOMMUs this time.

  Exceptions are the groundwork for the PAMU IOMMU from Freescale (for a
  PPC platform) and an extension to the IOMMU group interface.

  On the x86 side this includes a workaround for VT-d to disable
  interrupt remapping on broken chipsets.  On the AMD-Vi side the most
  important new feature is a kernel command-line interface to override
  broken information in IVRS ACPI tables and get interrupt remapping
  working this way.

  Besides that there are small fixes all over the place."

* tag 'iommu-updates-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (24 commits)
  iommu/tegra: Fix printk formats for dma_addr_t
  iommu: Add a function to find an iommu group by id
  iommu/vt-d: Remove warning for HPET scope type
  iommu: Move swap_pci_ref function to drivers/iommu/pci.h.
  iommu/vt-d: Disable translation if already enabled
  iommu/amd: fix error return code in early_amd_iommu_init()
  iommu/AMD: Per-thread IOMMU Interrupt Handling
  iommu: Include linux/err.h
  iommu/amd: Workaround for ERBT1312
  iommu/amd: Document ivrs_ioapic and ivrs_hpet parameters
  iommu/amd: Don't report firmware bugs with cmd-line ivrs overrides
  iommu/amd: Add ioapic and hpet ivrs override
  iommu/amd: Add early maps for ioapic and hpet
  iommu/amd: Extend IVRS special device data structure
  iommu/amd: Move add_special_device() to __init
  iommu: Fix compile warnings with forward declarations
  iommu/amd: Properly initialize irq-table lock
  iommu/amd: Use AMD specific data structure for irq remapping
  iommu/amd: Remove map_sg_no_iommu()
  iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets
  ...
2013-05-06 14:59:13 -07:00
Konrad Rzeszutek Wilk
7f1fc268c4 xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
If a user did:

	echo 0 > /sys/devices/system/cpu/cpu1/online
	echo 1 > /sys/devices/system/cpu/cpu1/online

we would (this a build with DEBUG enabled) get to:
smpboot: ++++++++++++++++++++=_---CPU UP  1
.. snip..
smpboot: Stack at about ffff880074c0ff44
smpboot: CPU1: has booted.

and hang. The RCU mechanism would kick in an try to IPI the CPU1
but the IPIs (and all other interrupts) would never arrive at the
CPU1. At first glance at least. A bit digging in the hypervisor
trace shows that (using xenanalyze):

[vla] d4v1 vec 243 injecting
   0.043163027 --|x d4v1 intr_window vec 243 src 5(vector) intr f3
]  0.043163639 --|x d4v1 vmentry cycles 1468
]  0.043164913 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254
   0.043164913 --|x d4v1 inj_virq vec 243  real
  [vla] d4v1 vec 243 injecting
   0.043164913 --|x d4v1 intr_window vec 243 src 5(vector) intr f3
]  0.043165526 --|x d4v1 vmentry cycles 1472
]  0.043166800 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254
   0.043166800 --|x d4v1 inj_virq vec 243  real
  [vla] d4v1 vec 243 injecting

there is a pending event (subsequent debugging shows it is the IPI
from the VCPU0 when smpboot.c on VCPU1 has done
"set_cpu_online(smp_processor_id(), true)") and the guest VCPU1 is
interrupted with the callback IPI (0xf3 aka 243) which ends up calling
__xen_evtchn_do_upcall.

The __xen_evtchn_do_upcall seems to do *something* but not acknowledge
the pending events. And the moment the guest does a 'cli' (that is the
ffffffff81673254 in the log above) the hypervisor is invoked again to
inject the IPI (0xf3) to tell the guest it has pending interrupts.
This repeats itself forever.

The culprit was the per_cpu(xen_vcpu, cpu) pointer. At the bootup
we set each per_cpu(xen_vcpu, cpu) to point to the
shared_info->vcpu_info[vcpu] but later on use the VCPUOP_register_vcpu_info
to register per-CPU  structures (xen_vcpu_setup).
This is used to allow events for more than 32 VCPUs and for performance
optimizations reasons.

When the user performs the VCPU hotplug we end up calling the
the xen_vcpu_setup once more. We make the hypercall which returns
-EINVAL as it does not allow multiple registration calls (and
already has re-assigned where the events are being set). We pick
the fallback case and set per_cpu(xen_vcpu, cpu) to point to the
shared_info->vcpu_info[vcpu] (which is a good fallback during bootup).
However the hypervisor is still setting events in the register
per-cpu structure (per_cpu(xen_vcpu_info, cpu)).

As such when the events are set by the hypervisor (such as timer one),
and when we iterate in __xen_evtchn_do_upcall we end up reading stale
events from the shared_info->vcpu_info[vcpu] instead of the
per_cpu(xen_vcpu_info, cpu) structures. Hence we never acknowledge the
events that the hypervisor has set and the hypervisor keeps on reminding
us to ack the events which we never do.

The fix is simple. Don't on the second time when xen_vcpu_setup is
called over-write the per_cpu(xen_vcpu, cpu) if it points to
per_cpu(xen_vcpu_info).

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: stable@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-06 11:29:17 -04:00