Commit Graph

22740 Commits

Author SHA1 Message Date
Minfei Huang
96e70f8328 x86/mm: Avoid overlap the fixmap area on i386
It is a problem when configuring high memory off where the
vmalloc reserve area could end up overlapping the early_ioremap
fixmap area on i386.

The ordering of the VMALLOC_RESERVE space is:

 FIXADDR_TOP
                       fixed_addresses
 FIXADDR_START
                       early_ioremap fixed addresses
 FIXADDR_BOOT_START
                       Persistent kmap area
 PKMAP_BASE
 VMALLOC_END
                       Vmalloc area
 VMALLOC_START
 high_memory

The available address we can use is lower than
FIXADDR_BOOT_START. So we will set the kmap boundary below the
FIXADDR_BOOT_START, if we configure high memory.

If we configure high memory, the vmalloc reserve area should
end up to PKMAP_BASE, otherwise should end up to
FIXADDR_BOOT_START.

Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/6B680A9E-6CE9-4C96-934B-CB01DCB58278@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 12:21:48 +01:00
Maciej W. Rozycki
60e684f0d6 x86/irq: Fix XT-PIC-XT-PIC in /proc/interrupts
Fix duplicate XT-PIC seen in /proc/interrupts on x86 systems
that make  use of 8259A Programmable Interrupt Controllers.
Specifically convert  output like this:

           CPU0
  0:      76573    XT-PIC-XT-PIC    timer
  1:         11    XT-PIC-XT-PIC    i8042
  2:          0    XT-PIC-XT-PIC    cascade
  4:          8    XT-PIC-XT-PIC    serial
  6:          3    XT-PIC-XT-PIC    floppy
  7:          0    XT-PIC-XT-PIC    parport0
  8:          1    XT-PIC-XT-PIC    rtc0
 10:        448    XT-PIC-XT-PIC    fddi0
 12:         23    XT-PIC-XT-PIC    eth0
 14:       2464    XT-PIC-XT-PIC    ide0
NMI:          0   Non-maskable interrupts
ERR:          0

to one like this:

           CPU0
  0:     122033    XT-PIC  timer
  1:         11    XT-PIC  i8042
  2:          0    XT-PIC  cascade
  4:          8    XT-PIC  serial
  6:          3    XT-PIC  floppy
  7:          0    XT-PIC  parport0
  8:          1    XT-PIC  rtc0
 10:        145    XT-PIC  fddi0
 12:         31    XT-PIC  eth0
 14:       2245    XT-PIC  ide0
NMI:          0   Non-maskable interrupts
ERR:          0

that is one like we used to have from ~2.2 till it was changed
sometime.

The rationale is there is no value in this duplicate
information, it  merely clutters output and looks ugly.  We only
have one handler for  8259A interrupts so there is no need to
give it a name separate from the  name already given to
irq_chip.

We could define meaningful names for handlers based on bits in
the ELCR  register on systems that have it or the value of the
LTIM bit we use in  ICW1 otherwise (hardcoded to 0 though with
MCA support gone), to tell  edge-triggered and level-triggered
inputs apart.  While that information  does not affect 8259A
interrupt handlers it could help people determine  which lines
are shareable and which are not.  That is material for a
separate change though.

Any tools that parse /proc/interrupts are supposed not to be
affected  since it was many years we used the format this change
converts back to.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1410260147190.21390@eddie.linux-mips.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 12:01:08 +01:00
Nicholas Mc Guire
a1a5831d29 x86/asm: Fix typo in arch/x86/kernel/asm_offset_64.c
Drop double entry for pt_regs_bx.

This seems to be a typo - resulting in a double entry in the
generated include/generated/asm-offsets.h, which is not necessary.

Build-tested and booted on x86 64 box to make sure it was not
doing any strange magic.... after all it was in the kernel in
this form for almost 10 years.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141027172805.GA19760@opentech.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:24:17 +01:00
Andy Lutomirski
1c0c1b93df x86_64/vdso: Clean up vgetcpu init and merge the vdso initcalls
Now vdso/vma.c has a single initcall and no references to
"vsyscall".

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/945c463e2804fedd8b08d63a040cbe85d55195aa.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:14 +01:00
Andy Lutomirski
61a492fb17 x86_64/vdso: Remove jiffies from the vvar page
I think that the jiffies vvar was once used for the vgetcpu
cache. That code is long gone, so let's just make jiffies be a
normal variable.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/fcfee6f8749af14d96373a9e2656354ad0b95499.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:13 +01:00
Andy Lutomirski
287e013108 x86/vdso: Make the PER_CPU segment 32 bits
IMO users ought not to be able to use 16-bit segments without
using modify_ldt.  Fortunately, it's impossible to break
espfix64 by loading the PER_CPU segment into SS because it's
PER_CPU is marked read-only and SS cannot contain an RO segment,
but marking PER_CPU as 32-bit is less fragile.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/179f490d659307873eefd09206bebd417e2ab5ad.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:12 +01:00
Andy Lutomirski
9c0080ef93 x86/vdso: Make the PER_CPU segment start out accessed
The first userspace attempt to read or write the PER_CPU segment
will write the accessed bit to the GDT.  This is visible to
userspace using the LAR instruction, and it also pointlessly
dirties a cache line.

Set the segment's accessed bit at boot to prevent userspace
access to segments from having side effects.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/ac63814ca4c637a08ec2fd0360d67ca67560a9ee.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:11 +01:00
Andy Lutomirski
258801563b x86/vdso: Change the PER_CPU segment to use struct desc_struct
This makes it easier to see what's going on.  It produces
exactly the same segment descriptor as the old code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/d492f7b55136cbc60f016adae79160707b2e03b7.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:10 +01:00
Andy Lutomirski
d4f829dd90 x86_64/vdso: Move getcpu code from vsyscall_64.c to vdso/vma.c
This is pure cut-and-paste.  At this point, vsyscall_64.c
contains only code needed for vsyscall emulation, but some of
the comments and function names are still confused.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/a244daf7d3cbe71afc08ad09fdfe1866ca1f1978.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:09 +01:00
Andy Lutomirski
b93590901a x86_64/vsyscall: Move all of the gate_area code to vsyscall_64.c
This code exists for the sole purpose of making the vsyscall
page look sort of like real userspace memory.  Move it so that
it lives with the rest of the vsyscall code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/a7ee266773671a05f00b7175ca65a0dd812d2e4b.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:08 +01:00
Andy Lutomirski
c4a7bba29b sched/x86: Add a comment clarifying LDT context switching
The code is correct, but only for a rather subtle reason.  This
confused me for quite a while when I read switch_mm, so clarify
the code to avoid confusing other people, too.

TBH, I wouldn't be surprised if this code was only correct by
accident.

[ I wouldn't normally send a comment-only patch, but it took me a long
  time to first figure out wtf was going on here, and then to figure
  out why this wasn't exploitable by malicious code, and then to
  figure out why this oddity had no user-visible effect at all.  Let's
  spare future readers the same confusion. ]

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/36275c99801a87d8dcf0502a41cf4e2ad81aae46.1412623954.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:11:57 +01:00
Andy Lutomirski
2c7577a758 sched/x86_64: Don't save flags on context switch
Now that the kernel always runs with clean flags (in particular,
NT is clear), there is no need to save and restore flags on
every context switch.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Sebastian Lackner <sebastian@fds-team.de>
Cc: Anish Bhatt <anish@chelsio.com>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/bf6fb790787eb95b922157838f52712c25dda157.1412187233.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:11:30 +01:00
Peter Zijlstra
7fb0f1de49 perf/x86: Fix compile warnings for intel_uncore
The uncore drivers require PCI and generate compile time warnings when
!CONFIG_PCI.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:03 +01:00
Peter Zijlstra (Intel)
65d71fe137 perf: Fix bogus kernel printk
Andy spotted the fail in what was intended as a conditional printk level.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Fixes: cc6cd47e73 ("perf/x86: Tone down kernel messages when the PMU check fails in a virtual environment")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141007124757.GH19379@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:01 +01:00
Oleg Nesterov
e2336f6e51 sched: Kill task_preempt_count()
task_preempt_count() is pointless if preemption counter is per-cpu,
currently this is x86 only. It is only valid if the task is not
running, and even in this case the only info it can provide is the
state of PREEMPT_ACTIVE bit.

Change its single caller to check p->on_rq instead, this should be
the same if p->state != TASK_RUNNING, and kill this helper.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/20141008183348.GC17495@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:56 +01:00
Oleg Nesterov
009f60e276 sched: stop the unbound recursion in preempt_schedule_context()
preempt_schedule_context() does preempt_enable_notrace() at the end
and this can call the same function again; exception_exit() is heavy
and it is quite possible that need-resched is true again.

1. Change this code to dec preempt_count() and check need_resched()
   by hand.

2. As Linus suggested, we can use the PREEMPT_ACTIVE bit and avoid
   the enable/disable dance around __schedule(). But in this case
   we need to move into sched/core.c.

3. Cosmetic, but x86 forgets to declare this function. This doesn't
   really matter because it is only called by asm helpers, still it
   make sense to add the declaration into asm/preempt.h to match
   preempt_schedule().

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20141005202322.GB27962@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:46:05 +01:00
Weijie Yang
3c325f8233 x86, cma: Reserve DMA contiguous area after initmem_init()
Fengguang Wu reported a boot crash on the x86 platform
via the 0-day Linux Kernel Performance Test:

  cma: dma_contiguous_reserve: reserving 31 MiB for global area
  BUG: Int 6: CR2   (null)
  [<41850786>] dump_stack+0x16/0x18
  [<41d2b1db>] early_idt_handler+0x6b/0x6b
  [<41072227>] ? __phys_addr+0x2e/0xca
  [<41d4ee4d>] cma_declare_contiguous+0x3c/0x2d7
  [<41d6d359>] dma_contiguous_reserve_area+0x27/0x47
  [<41d6d4d1>] dma_contiguous_reserve+0x158/0x163
  [<41d33e0f>] setup_arch+0x79b/0xc68
  [<41d2b7cf>] start_kernel+0x9c/0x456
  [<41d2b2ca>] i386_start_kernel+0x79/0x7d

(See details at: https://lkml.org/lkml/2014/10/8/708)

It is because dma_contiguous_reserve() is called before
initmem_init() in x86, the variable high_memory is not
initialized but accessed by __pa(high_memory) in
dma_contiguous_reserve().

This patch moves dma_contiguous_reserve() after initmem_init()
so that high_memory is initialized before accessed.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: iamjoonsoo.kim@lge.com
Cc: 'Linux-MM' <linux-mm@kvack.org>
Cc: 'Weijie Yang' <weijie.yang.kh@gmail.com>
Link: http://lkml.kernel.org/r/000101cfef69%2431e528a0%2495af79e0%24%25yang@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 07:36:50 +01:00
Dave Airlie
bbf0ef0334 Merge tag 'drm-intel-next-2014-10-03-no-ppgtt' of git://anongit.freedesktop.org/drm-intel into drm-next
Ok, new attempt, this time around with full ppgtt disabled again.

drm-intel-next-2014-10-03:
- first batch of skl stage 1 enabling
- fixes from Rodrigo to the PSR, fbc and sink crc code
- kerneldoc for the frontbuffer tracking code, runtime pm code and the basic
  interrupt enable/disable functions
- smaller stuff all over
drm-intel-next-2014-09-19:
- bunch more i830M fixes from Ville
- full ppgtt now again enabled by default
- more ppgtt fixes from Michel Thierry and Chris Wilson
- plane config work from Gustavo Padovan
- spinlock clarifications
- piles of smaller improvements all over, as usual

* tag 'drm-intel-next-2014-10-03-no-ppgtt' of git://anongit.freedesktop.org/drm-intel: (114 commits)
  Revert "drm/i915: Enable full PPGTT on gen7"
  drm/i915: Update DRIVER_DATE to 20141003
  drm/i915: Remove the duplicated logic between the two shrink phases
  drm/i915: kerneldoc for interrupt enable/disable functions
  drm/i915: Use dev_priv instead of dev in irq setup functions
  drm/i915: s/pm._irqs_disabled/pm.irqs_enabled/
  drm/i915: Clear TX FIFO reset master override bits on chv
  drm/i915: Make sure hardware uses the correct swing margin/deemph bits on chv
  drm/i915: make sink_crc return -EIO on aux read/write failure
  drm/i915: Constify send buffer for intel_dp_aux_ch
  drm/i915: De-magic the PSR AUX message
  drm/i915: Reinstate error level message for non-simulated gpu hangs
  drm/i915: Kerneldoc for intel_runtime_pm.c
  drm/i915: Call runtime_pm_disable directly
  drm/i915: Move intel_display_set_init_power to intel_runtime_pm.c
  drm/i915: Bikeshed rpm functions name a bit.
  drm/i915: Extract intel_runtime_pm.c
  drm/i915: Remove intel_modeset_suspend_hw
  drm/i915: spelling fixes for frontbuffer tracking kerneldoc
  drm/i915: Tighting frontbuffer tracking around flips
  ...
2014-10-28 12:37:58 +10:00
Subhransu S. Prusty
9a80e8f597 ASoC: Intel: mrfld: Define sst_res_info for acpi
To query resources in ACPI systems we need to define a data structure. This
would be set as platform_info for the devices.

Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-27 18:02:38 +00:00
Subhransu S. Prusty
43c5e23197 ASoC: Intel: mrfld - Define ipc_info structure
This will be used to abstract the differances in ipc offsets for different
chips.

Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-27 18:02:38 +00:00
Eric Paris
26c2d2b391 i386/audit: stop scribbling on the stack frame
git commit b4f0d3755c was very very dumb.
It was writing over %esp/pt_regs semi-randomly on i686  with the expected
"system can't boot" results.  As noted in:

https://bugs.freedesktop.org/show_bug.cgi?id=85277

This patch stops fscking with pt_regs.  Instead it sets up the registers
for the call to __audit_syscall_entry in the most obvious conceivable
way.  It then does just a tiny tiny touch of magic.  We need to get what
started in PT_EDX into 0(%esp) and PT_ESI into 4(%esp).  This is as easy
as a pair of pushes.

After the call to __audit_syscall_entry all we need to do is get that
now useless junk off the stack (pair of pops) and reload %eax with the
original syscall so other stuff can keep going about it's business.

Reported-by: Paulo Zanoni <przanoni@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Link: http://lkml.kernel.org/r/1414037043-30647-1-git-send-email-eparis@redhat.com
Cc: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-10-24 13:27:56 -07:00
H. Peter Anvin
db65bcfd95 Merge tag 'v3.18-rc1' into x86/urgent
Reason:
Need to apply audit patch on top of v3.18-rc1.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-10-24 13:26:37 -07:00
Linus Torvalds
96971e9aa9 Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
 "This is a pretty large update.  I think it is roughly as big as what I
  usually had for the _whole_ rc period.

  There are a few bad bugs where the guest can OOPS or crash the host.
  We have also started looking at attack models for nested
  virtualization; bugs that usually result in the guest ring 0 crashing
  itself become more worrisome if you have nested virtualization,
  because the nested guest might bring down the non-nested guest as
  well.  For current uses of nested virtualization these do not really
  have a security impact, but you never know and bugs are bugs
  nevertheless.

  A lot of these bugs are in 3.17 too, resulting in a large number of
  stable@ Ccs.  I checked that all the patches apply there with no
  conflicts"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: vfio: fix unregister kvm_device_ops of vfio
  KVM: x86: Wrong assertion on paging_tmpl.h
  kvm: fix excessive pages un-pinning in kvm_iommu_map error path.
  KVM: x86: PREFETCH and HINT_NOP should have SrcMem flag
  KVM: x86: Emulator does not decode clflush well
  KVM: emulate: avoid accessing NULL ctxt->memopp
  KVM: x86: Decoding guest instructions which cross page boundary may fail
  kvm: x86: don't kill guest on unknown exit reason
  kvm: vmx: handle invvpid vm exit gracefully
  KVM: x86: Handle errors when RIP is set during far jumps
  KVM: x86: Emulator fixes for eip canonical checks on near branches
  KVM: x86: Fix wrong masking on relative jump/call
  KVM: x86: Improve thread safety in pit
  KVM: x86: Prevent host from panicking on shared MSR writes.
  KVM: x86: Check non-canonical addresses upon WRMSR
2014-10-24 12:42:55 -07:00
Linus Torvalds
20ca57cde5 Merge tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen bug fixes from David Vrabel:

 - Fix regression in xen_clocksource_read() which caused all Xen guests
   to crash early in boot.
 - Several fixes for super rare race conditions in the p2m.
 - Assorted other minor fixes.

* tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/pci: Allocate memory for physdev_pci_device_add's optarr
  x86/xen: panic on bad Xen-provided memory map
  x86/xen: Fix incorrect per_cpu accessor in xen_clocksource_read()
  x86/xen: avoid race in p2m handling
  x86/xen: delay construction of mfn_list_list
  x86/xen: avoid writing to freed memory after race in p2m handling
  xen/balloon: Don't continue ballooning when BP_ECANCELED is encountered
2014-10-24 12:41:50 -07:00
Nadav Amit
1715d0dcb0 KVM: x86: Wrong assertion on paging_tmpl.h
Even after the recent fix, the assertion on paging_tmpl.h is triggered.
Apparently, the assertion wants to check that the PAE is always set on
long-mode, but does it in incorrect way.  Note that the assertion is not
enabled unless the code is debugged by defining MMU_DEBUG.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:30:37 +02:00
Nadav Amit
3f6f1480d8 KVM: x86: PREFETCH and HINT_NOP should have SrcMem flag
The decode phase of the x86 emulator assumes that every instruction with the
ModRM flag, and which can be used with RIP-relative addressing, has either
SrcMem or DstMem.  This is not the case for several instructions - prefetch,
hint-nop and clflush.

Adding SrcMem|NoAccess for prefetch and hint-nop and SrcMem for clflush.

This fixes CVE-2014-8480.

Fixes: 41061cdb98
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:30:36 +02:00
Nadav Amit
13e457e0ee KVM: x86: Emulator does not decode clflush well
Currently, all group15 instructions are decoded as clflush (e.g., mfence,
xsave).  In addition, the clflush instruction requires no prefix (66/f2/f3)
would exist. If prefix exists it may encode a different instruction (e.g.,
clflushopt).

Creating a group for clflush, and different group for each prefix.

This has been the case forever, but the next patch needs the cflush group
in order to fix a bug introduced in 3.17.

Fixes: 41061cdb98
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:30:36 +02:00
Paolo Bonzini
a430c91663 KVM: emulate: avoid accessing NULL ctxt->memopp
A failure to decode the instruction can cause a NULL pointer access.
This is fixed simply by moving the "done" label as close as possible
to the return.

This fixes CVE-2014-8481.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Cc: stable@vger.kernel.org
Fixes: 41061cdb98
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:30:35 +02:00
Nadav Amit
08da44aedb KVM: x86: Decoding guest instructions which cross page boundary may fail
Once an instruction crosses a page boundary, the size read from the second page
disregards the common case that part of the operand resides on the first page.
As a result, fetch of long insturctions may fail, and thereby cause the
decoding to fail as well.

Cc: stable@vger.kernel.org
Fixes: 5cfc7e0f5e
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:18 +02:00
Michael S. Tsirkin
2bc19dc375 kvm: x86: don't kill guest on unknown exit reason
KVM_EXIT_UNKNOWN is a kvm bug, we don't really know whether it was
triggered by a priveledged application.  Let's not kill the guest: WARN
and inject #UD instead.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:17 +02:00
Petr Matousek
a642fc3050 kvm: vmx: handle invvpid vm exit gracefully
On systems with invvpid instruction support (corresponding bit in
IA32_VMX_EPT_VPID_CAP MSR is set) guest invocation of invvpid
causes vm exit, which is currently not handled and results in
propagation of unknown exit to userspace.

Fix this by installing an invvpid vm exit handler.

This is CVE-2014-3646.

Cc: stable@vger.kernel.org
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:17 +02:00
Nadav Amit
d1442d85cc KVM: x86: Handle errors when RIP is set during far jumps
Far jmp/call/ret may fault while loading a new RIP.  Currently KVM does not
handle this case, and may result in failed vm-entry once the assignment is
done.  The tricky part of doing so is that loading the new CS affects the
VMCS/VMCB state, so if we fail during loading the new RIP, we are left in
unconsistent state.  Therefore, this patch saves on 64-bit the old CS
descriptor and restores it if loading RIP failed.

This fixes CVE-2014-3647.

Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:16 +02:00
Nadav Amit
234f3ce485 KVM: x86: Emulator fixes for eip canonical checks on near branches
Before changing rip (during jmp, call, ret, etc.) the target should be asserted
to be canonical one, as real CPUs do.  During sysret, both target rsp and rip
should be canonical. If any of these values is noncanonical, a #GP exception
should occur.  The exception to this rule are syscall and sysenter instructions
in which the assigned rip is checked during the assignment to the relevant
MSRs.

This patch fixes the emulator to behave as real CPUs do for near branches.
Far branches are handled by the next patch.

This fixes CVE-2014-3647.

Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:16 +02:00
Nadav Amit
05c83ec9b7 KVM: x86: Fix wrong masking on relative jump/call
Relative jumps and calls do the masking according to the operand size, and not
according to the address size as the KVM emulator does today.

This patch fixes KVM behavior.

Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:15 +02:00
Andy Honig
2febc83913 KVM: x86: Improve thread safety in pit
There's a race condition in the PIT emulation code in KVM.  In
__kvm_migrate_pit_timer the pit_timer object is accessed without
synchronization.  If the race condition occurs at the wrong time this
can crash the host kernel.

This fixes CVE-2014-3611.

Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:14 +02:00
Andy Honig
8b3c3104c3 KVM: x86: Prevent host from panicking on shared MSR writes.
The previous patch blocked invalid writes directly when the MSR
is written.  As a precaution, prevent future similar mistakes by
gracefulling handle GPs caused by writes to shared MSRs.

Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
[Remove parts obsoleted by Nadav's patch. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:08 +02:00
Nadav Amit
854e8bb1aa KVM: x86: Check non-canonical addresses upon WRMSR
Upon WRMSR, the CPU should inject #GP if a non-canonical value (address) is
written to certain MSRs. The behavior is "almost" identical for AMD and Intel
(ignoring MSRs that are not implemented in either architecture since they would
anyhow #GP). However, IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if
non-canonical address is written on Intel but not on AMD (which ignores the top
32-bits).

Accordingly, this patch injects a #GP on the MSRs which behave identically on
Intel and AMD.  To eliminate the differences between the architecutres, the
value which is written to IA32_SYSENTER_ESP and IA32_SYSENTER_EIP is turned to
canonical value before writing instead of injecting a #GP.

Some references from Intel and AMD manuals:

According to Intel SDM description of WRMSR instruction #GP is expected on
WRMSR "If the source register contains a non-canonical address and ECX
specifies one of the following MSRs: IA32_DS_AREA, IA32_FS_BASE, IA32_GS_BASE,
IA32_KERNEL_GS_BASE, IA32_LSTAR, IA32_SYSENTER_EIP, IA32_SYSENTER_ESP."

According to AMD manual instruction manual:
LSTAR/CSTAR (SYSCALL): "The WRMSR instruction loads the target RIP into the
LSTAR and CSTAR registers.  If an RIP written by WRMSR is not in canonical
form, a general-protection exception (#GP) occurs."
IA32_GS_BASE and IA32_FS_BASE (WRFSBASE/WRGSBASE): "The address written to the
base field must be in canonical form or a #GP fault will occur."
IA32_KERNEL_GS_BASE (SWAPGS): "The address stored in the KernelGSbase MSR must
be in canonical form."

This patch fixes CVE-2014-3610.

Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:21:08 +02:00
Linus Torvalds
816fb4175c Merge tag 'remove-weak-declarations' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull weak function declaration removal from Bjorn Helgaas:
 "The "weak" attribute is commonly used for the default version of a
  function, where an architecture can override it by providing a strong
  version.

  Some header file declarations included the "weak" attribute.  That's
  error-prone because it causes every implementation to be weak, with no
  strong version at all, and the linker chooses one based on link order.

  What we want is the "weak" attribute only on the *definition* of the
  default implementation.  These changes remove "weak" from the
  declarations, leaving it on the default definitions"

* tag 'remove-weak-declarations' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  uprobes: Remove "weak" from function declarations
  memory-hotplug: Remove "weak" from memory_block_size_bytes() declaration
  kgdb: Remove "weak" from kgdb_arch_pc() declaration
  ARC: kgdb: generic kgdb_arch_pc() suffices
  vmcore: Remove "weak" from function declarations
  clocksource: Remove "weak" from clocksource_default_clock() declaration
  x86, intel-mid: Remove "weak" from function declarations
  audit: Remove "weak" from audit_classify_compat_syscall() declaration
2014-10-23 15:04:27 -07:00
Linus Torvalds
8c81f48e16 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI updates from Peter Anvin:
 "This patchset falls under the "maintainers that grovel" clause in the
  v3.18-rc1 announcement.  We had intended to push it late in the merge
  window since we got it into the -tip tree relatively late.

  Many of these are relatively simple things, but there are a couple of
  key bits, especially Ard's and Matt's patches"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  rtc: Disable EFI rtc for x86
  efi: rtc-efi: Export platform:rtc-efi as module alias
  efi: Delete the in_nmi() conditional runtime locking
  efi: Provide a non-blocking SetVariable() operation
  x86/efi: Adding efi_printks on memory allocationa and pci.reads
  x86/efi: Mark initialization code as such
  x86/efi: Update comment regarding required phys mapped EFI services
  x86/efi: Unexport add_efi_memmap variable
  x86/efi: Remove unused efi_call* macros
  efi: Resolve some shadow warnings
  arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
  ia64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
  x86: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
  efi: Introduce efi_md_typeattr_format()
  efi: Add macro for EFI_MEMORY_UCE memory attribute
  x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode
  arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi
  arm64/efi: uefi_init error handling fix
  efi: Add kernel param efi=noruntime
  lib: Add a generic cmdline parse function parse_option_str
  ...
2014-10-23 14:45:09 -07:00
Martin Kelly
1ea644c8f9 x86/xen: panic on bad Xen-provided memory map
Panic if Xen provides a memory map with 0 entries. Although this is
unlikely, it is better to catch the error at the point of seeing the map
than later on as a symptom of some other crash.

Signed-off-by: Martin Kelly <martkell@amazon.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-23 16:24:02 +01:00
Boris Ostrovsky
3251f20b89 x86/xen: Fix incorrect per_cpu accessor in xen_clocksource_read()
Commit 89cbc76768 ("x86: Replace __get_cpu_var uses") replaced
__get_cpu_var() with this_cpu_ptr() in xen_clocksource_read() in such a
way that instead of accessing a structure pointed to by a per-cpu pointer
we are trying to get to a per-cpu structure.

__this_cpu_read() of the pointer is the more appropriate accessor.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-23 16:24:02 +01:00
Juergen Gross
3a0e94f8ea x86/xen: avoid race in p2m handling
When a new p2m leaf is allocated this leaf is linked into the p2m tree
via cmpxchg. Unfortunately the compare value for checking the success
of the update is read after checking for the need of a new leaf. It is
possible that a new leaf has been linked into the tree concurrently
in between. This could lead to a leaked memory page and to the loss of
some p2m entries.

Avoid the race by using the read compare value for checking the need
of a new p2m leaf and use ACCESS_ONCE() to get it.

There are other places which seem to need ACCESS_ONCE() to ensure
proper operation. Change them accordingly.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-23 16:24:02 +01:00
Juergen Gross
2c185687ab x86/xen: delay construction of mfn_list_list
The 3 level p2m tree for the Xen tools is constructed very early at
boot by calling xen_build_mfn_list_list(). Memory needed for this tree
is allocated via extend_brk().

As this tree (other than the kernel internal p2m tree) is only needed
for domain save/restore, live migration and crash dump analysis it
doesn't matter whether it is constructed very early or just some
milliseconds later when memory allocation is possible by other means.

This patch moves the call of xen_build_mfn_list_list() just after
calling xen_pagetable_p2m_copy() simplifying this function, too, as it
doesn't have to bother with two parallel trees now. The same applies
for some other internal functions.

While simplifying code, make early_can_reuse_p2m_middle() static and
drop the unused second parameter. p2m_mid_identity_mfn can be removed
as well, it isn't used either.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-23 16:24:02 +01:00
Juergen Gross
239af7c713 x86/xen: avoid writing to freed memory after race in p2m handling
In case a race was detected during allocation of a new p2m tree
element in alloc_p2m() the new allocated mid_mfn page is freed without
updating the pointer to the found value in the tree. This will result
in overwriting the just freed page with the mfn of the p2m leaf.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-23 16:24:01 +01:00
Bjorn Helgaas
754f0da0dc x86, intel-mid: Remove "weak" from function declarations
For the following interfaces:

  get_penwell_ops()
  get_cloverview_ops()
  get_tangier_ops()

there is only one implementation, so they do not need to be marked "weak".

Remove the "weak" attribute from their declarations.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
CC: David Cohen <david.a.cohen@linux.intel.com>
CC: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
CC: x86@kernel.org
2014-10-22 16:14:03 -06:00
Andy Lutomirski
b47dcbdc51 x86, apic: Handle a bad TSC more gracefully
If the TSC is unusable or disabled, then this patch fixes:

 - Confusion while trying to clear old APIC interrupts.
 - Division by zero and incorrect programming of the TSC deadline
   timer.

This fixes boot if the CPU has a TSC deadline timer but a missing or
broken TSC.  The failure to boot can be observed with qemu using
-cpu qemu64,-tsc,+tsc-deadline

This also happens to me in nested KVM for unknown reasons.
With this patch, I can boot cleanly (although without a TSC).

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Bandan Das <bsd@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/e2fa274e498c33988efac0ba8b7e3120f7f92d78.1413393027.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-10-22 21:31:46 +02:00
Borislav Petkov
a3a529d104 x86, MCE, AMD: Drop software-defined bank in error thresholding
Aravind had the good question about why we're assigning a
software-defined bank when reporting error thresholding errors instead
of simply using the bank which reports the last error causing the
overflow.

Digging through git history, it pointed to

9526866439 ("[PATCH] x86_64: mce_amd support for family 0x10 processors")

which added that functionality. The problem with this, however, is that
tools don't know about software-defined banks and get puzzled. So drop
that K8_MCE_THRESHOLD_BASE and simply use the hw bank reporting the
thresholding interrupt.

Save us a couple of MSR reads while at it.

Reported-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>
Link: https://lkml.kernel.org/r/5435B206.60402@amd.com
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-10-21 22:28:48 +02:00
Chen Yucong
69b9575835 x86, MCE, AMD: Move invariant code out from loop body
Assigning to mce_threshold_vector is loop-invariant code in
mce_amd_feature_init(). So do it only once, out of loop body.

Signed-off-by: Chen Yucong <slaoub@gmail.com>
Link: http://lkml.kernel.org/r/1412263212.8085.6.camel@debian
[ Boris: commit message corrections. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-10-21 22:12:56 +02:00
Chen Yucong
44612a3ac6 x86, MCE, AMD: Correct thresholding error logging
mce_setup() does not gather the content of IA32_MCG_STATUS, so it
should be read explicitly. Moreover, we need to clear IA32_MCx_STATUS
to avoid that mce_log() logs the processed threshold event again
at next time.

But we do the logging ourselves and machine_check_poll() is completely
useless there. So kill it.

Signed-off-by: Chen Yucong <slaoub@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-10-21 22:12:22 +02:00
Chen Yucong
4b737d78a8 x86, MCE, AMD: Use macros to compute bank MSRs
Avoid open coded calculations for bank MSRs by hiding the index
of higher bank MSRs in well-defined macros.

No semantic changes.

Signed-off-by: Chen Yucong <slaoub@gmail.com>
Link: http://lkml.kernel.org/r/1411438561-24319-1-git-send-email-slaoub@gmail.com
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-10-21 22:07:24 +02:00