Commit Graph

14549 Commits

Author SHA1 Message Date
Benoit Cousson
1f52299ec0 Merge branch 'irqdomain/next' of git://git.secretlab.ca/git/linux-2.6 into for_3.4/dt_irq_domain2 2012-02-27 10:32:39 +01:00
Grant Likely
b4e518547d irq_domain/x86: Convert x86 (embedded) to use common irq_domain
This patch removes the x86-specific definition of irq_domain and replaces
it with the common implementation.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
2012-02-23 14:37:47 -07:00
Linus Torvalds
34ddc81a23 i387: re-introduce FPU state preloading at context switch time
After all the FPU state cleanups and finally finding the problem that
caused all our FPU save/restore problems, this re-introduces the
preloading of FPU state that was removed in commit b3b0870ef3 ("i387:
do not preload FPU state at task switch time").

However, instead of simply reverting the removal, this reimplements
preloading with several fixes, most notably

 - properly abstracted as a true FPU state switch, rather than as
   open-coded save and restore with various hacks.

   In particular, implementing it as a proper FPU state switch allows us
   to optimize the CR0.TS flag accesses: there is no reason to set the
   TS bit only to then almost immediately clear it again.  CR0 accesses
   are quite slow and expensive, don't flip the bit back and forth for
   no good reason.

 - Make sure that the same model works for both x86-32 and x86-64, so
   that there are no gratuitous differences between the two due to the
   way they save and restore segment state differently due to
   architectural differences that really don't matter to the FPU state.

 - Avoid exposing the "preload" state to the context switch routines,
   and in particular allow the concept of lazy state restore: if nothing
   else has used the FPU in the meantime, and the process is still on
   the same CPU, we can avoid restoring state from memory entirely, just
   re-expose the state that is still in the FPU unit.

   That optimized lazy restore isn't actually implemented here, but the
   infrastructure is set up for it.  Of course, older CPU's that use
   'fnsave' to save the state cannot take advantage of this, since the
   state saving also trashes the state.

In other words, there is now an actual _design_ to the FPU state saving,
rather than just random historical baggage.  Hopefully it's easier to
follow as a result.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-18 14:03:48 -08:00
Linus Torvalds
f94edacf99 i387: move TS_USEDFPU flag from thread_info to task_struct
This moves the bit that indicates whether a thread has ownership of the
FPU from the TS_USEDFPU bit in thread_info->status to a word of its own
(called 'has_fpu') in task_struct->thread.has_fpu.

This fixes two independent bugs at the same time:

 - changing 'thread_info->status' from the scheduler causes nasty
   problems for the other users of that variable, since it is defined to
   be thread-synchronous (that's what the "TS_" part of the naming was
   supposed to indicate).

   So perfectly valid code could (and did) do

	ti->status |= TS_RESTORE_SIGMASK;

   and the compiler was free to do that as separate load, or and store
   instructions.  Which can cause problems with preemption, since a task
   switch could happen in between, and change the TS_USEDFPU bit. The
   change to TS_USEDFPU would be overwritten by the final store.

   In practice, this seldom happened, though, because the 'status' field
   was seldom used more than once, so gcc would generally tend to
   generate code that used a read-modify-write instruction and thus
   happened to avoid this problem - RMW instructions are naturally low
   fat and preemption-safe.

 - On x86-32, the current_thread_info() pointer would, during interrupts
   and softirqs, point to a *copy* of the real thread_info, because
   x86-32 uses %esp to calculate the thread_info address, and thus the
   separate irq (and softirq) stacks would cause these kinds of odd
   thread_info copy aliases.

   This is normally not a problem, since interrupts aren't supposed to
   look at thread information anyway (what thread is running at
   interrupt time really isn't very well-defined), but it confused the
   heck out of irq_fpu_usable() and the code that tried to squirrel
   away the FPU state.

   (It also caused untold confusion for us poor kernel developers).

It also turns out that using 'task_struct' is actually much more natural
for most of the call sites that care about the FPU state, since they
tend to work with the task struct for other reasons anyway (ie
scheduling).  And the FPU data that we are going to save/restore is
found there too.

Thanks to Arjan Van De Ven <arjan@linux.intel.com> for pointing us to
the %esp issue.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Reported-and-tested-by: Raphael Prevost <raphael@buro.asia>
Acked-and-tested-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-18 10:19:41 -08:00
Linus Torvalds
4903062b54 i387: move AMD K7/K8 fpu fxsave/fxrstor workaround from save to restore
The AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is
pending.  In order to not leak FIP state from one process to another, we
need to do a floating point load after the fxsave of the old process,
and before the fxrstor of the new FPU state.  That resets the state to
the (uninteresting) kernel load, rather than some potentially sensitive
user information.

We used to do this directly after the FPU state save, but that is
actually very inconvenient, since it

 (a) corrupts what is potentially perfectly good FPU state that we might
     want to lazy avoid restoring later and

 (b) on x86-64 it resulted in a very annoying ordering constraint, where
     "__unlazy_fpu()" in the task switch needs to be delayed until after
     the DS segment has been reloaded just to get the new DS value.

Coupling it to the fxrstor instead of the fxsave automatically avoids
both of these issues, and also ensures that we only do it when actually
necessary (the FP state after a save may never actually get used).  It's
simply a much more natural place for the leaked state cleanup.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16 19:11:15 -08:00
Linus Torvalds
b3b0870ef3 i387: do not preload FPU state at task switch time
Yes, taking the trap to re-load the FPU/MMX state is expensive, but so
is spending several days looking for a bug in the state save/restore
code.  And the preload code has some rather subtle interactions with
both paravirtualization support and segment state restore, so it's not
nearly as simple as it should be.

Also, now that we no longer necessarily depend on a single bit (ie
TS_USEDFPU) for keeping track of the state of the FPU, we migth be able
to do better.  If we are really switching between two processes that
keep touching the FP state, save/restore is inevitable, but in the case
of having one process that does most of the FPU usage, we may actually
be able to do much better than the preloading.

In particular, we may be able to keep track of which CPU the process ran
on last, and also per CPU keep track of which process' FP state that CPU
has.  For modern CPU's that don't destroy the FPU contents on save time,
that would allow us to do a lazy restore by just re-enabling the
existing FPU state - with no restore cost at all!

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16 15:45:23 -08:00
Linus Torvalds
6d59d7a9f5 i387: don't ever touch TS_USEDFPU directly, use helper functions
This creates three helper functions that do the TS_USEDFPU accesses, and
makes everybody that used to do it by hand use those helpers instead.

In addition, there's a couple of helper functions for the "change both
CR0.TS and TS_USEDFPU at the same time" case, and the places that do
that together have been changed to use those.  That means that we have
fewer random places that open-code this situation.

The intent is partly to clarify the code without actually changing any
semantics yet (since we clearly still have some hard to reproduce bug in
this area), but also to make it much easier to use another approach
entirely to caching the CR0.TS bit for software accesses.

Right now we use a bit in the thread-info 'status' variable (this patch
does not change that), but we might want to make it a full field of its
own or even make it a per-cpu variable.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16 13:33:12 -08:00
Linus Torvalds
b6c66418dc i387: move TS_USEDFPU clearing out of __save_init_fpu and into callers
Touching TS_USEDFPU without touching CR0.TS is confusing, so don't do
it.  By moving it into the callers, we always do the TS_USEDFPU next to
the CR0.TS accesses in the source code, and it's much easier to see how
the two go hand in hand.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16 12:22:48 -08:00
Linus Torvalds
15d8791cae i387: fix x86-64 preemption-unsafe user stack save/restore
Commit 5b1cbac377 ("i387: make irq_fpu_usable() tests more robust")
added a sanity check to the #NM handler to verify that we never cause
the "Device Not Available" exception in kernel mode.

However, that check actually pinpointed a (fundamental) race where we do
cause that exception as part of the signal stack FPU state save/restore
code.

Because we use the floating point instructions themselves to save and
restore state directly from user mode, we cannot do that atomically with
testing the TS_USEDFPU bit: the user mode access itself may cause a page
fault, which causes a task switch, which saves and restores the FP/MMX
state from the kernel buffers.

This kind of "recursive" FP state save is fine per se, but it means that
when the signal stack save/restore gets restarted, it will now take the
'#NM' exception we originally tried to avoid.  With preemption this can
happen even without the page fault - but because of the user access, we
cannot just disable preemption around the save/restore instruction.

There are various ways to solve this, including using the
"enable/disable_page_fault()" helpers to not allow page faults at all
during the sequence, and fall back to copying things by hand without the
use of the native FP state save/restore instructions.

However, the simplest thing to do is to just allow the #NM from kernel
space, but fix the race in setting and clearing CR0.TS that this all
exposed: the TS bit changes and the TS_USEDFPU bit absolutely have to be
atomic wrt scheduling, so while the actual state save/restore can be
interrupted and restarted, the act of actually clearing/setting CR0.TS
and the TS_USEDFPU bit together must not.

Instead of just adding random "preempt_disable/enable()" calls to what
is already excessively ugly code, this introduces some helper functions
that mostly mirror the "kernel_fpu_begin/end()" functionality, just for
the user state instead.

Those helper functions should probably eventually replace the other
ad-hoc CR0.TS and TS_USEDFPU tests too, but I'll need to think about it
some more: the task switching functionality in particular needs to
expose the difference between the 'prev' and 'next' threads, while the
new helper functions intentionally were written to only work with
'current'.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16 09:15:04 -08:00
Linus Torvalds
c38e234562 i387: fix sense of sanity check
The check for save_init_fpu() (introduced in commit 5b1cbac377: "i387:
make irq_fpu_usable() tests more robust") was the wrong way around, but
I hadn't noticed, because my "tests" were bogus: the FPU exceptions are
disabled by default, so even doing a divide by zero never actually
triggers this code at all unless you do extra work to enable them.

So if anybody did enable them, they'd get one spurious warning.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-15 08:05:18 -08:00
Linus Torvalds
694ce18ec3 Two fixes for VCPU offlining; One to fix the string format exposed
by the xen-pci[front|back] to conform to the one used in majority of
 PCI drivers; Two fixes to make the code more resilient to invalid
 configurations.
 
 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Merge tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Two fixes for VCPU offlining; One to fix the string format exposed
by the xen-pci[front|back] to conform to the one used in majority of
PCI drivers; Two fixes to make the code more resilient to invalid
configurations.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

* tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xenbus_dev: add missing error check to watch handling
  xen/pci[front|back]: Use %d instead of %1x for displaying PCI devfn.
  xen pvhvm: do not remap pirqs onto evtchns if !xen_have_vector_callback
  xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic.
  xen/bootup: During bootup suppress XENBUS: Unable to read cpu state
2012-02-14 15:20:11 -08:00
Linus Torvalds
5b1cbac377 i387: make irq_fpu_usable() tests more robust
Some code - especially the crypto layer - wants to use the x86
FP/MMX/AVX register set in what may be interrupt (typically softirq)
context.

That *can* be ok, but the tests for when it was ok were somewhat
suspect.  We cannot touch the thread-specific status bits either, so
we'd better check that we're not going to try to save FP state or
anything like that.

Now, it may be that the TS bit is always cleared *before* we set the
USEDFPU bit (and only set when we had already cleared the USEDFP
before), so the TS bit test may actually have been sufficient, but it
certainly was not obviously so.

So this explicitly verifies that we will not touch the TS_USEDFPU bit,
and adds a few related sanity-checks.  Because it seems that somehow
AES-NI is corrupting user FP state.  The cause is not clear, and this
patch doesn't fix it, but while debugging it I really wanted the code to
be more obviously correct and robust.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-13 13:56:14 -08:00
Linus Torvalds
be98c2cdb1 i387: math_state_restore() isn't called from asm
It was marked asmlinkage for some really old and stale legacy reasons.
Fix that and the equally stale comment.

Noticed when debugging the irq_fpu_usable() bugs.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-13 13:47:25 -08:00
Linus Torvalds
ce2814f227 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix double start/stop in x86_pmu_start()
  perf evsel: Fix an issue where perf report fails to show the proper percentage
  perf tools: Fix prefix matching for kernel maps
  perf tools: Fix perf stack to non executable on x86_64
  perf: Remove deprecated WARN_ON_ONCE()
2012-02-10 09:05:07 -08:00
Stephane Eranian
f39d47ff81 perf: Fix double start/stop in x86_pmu_start()
The following patch fixes a bug introduced by the following
commit:

        e050e3f0a7 ("perf: Fix broken interrupt rate throttling")

The patch caused the following warning to pop up depending on
the sampling frequency adjustments:

  ------------[ cut here ]------------
  WARNING: at arch/x86/kernel/cpu/perf_event.c:995 x86_pmu_start+0x79/0xd4()

It was caused by the following call sequence:

perf_adjust_freq_unthr_context.part() {
     stop()
     if (delta > 0) {
          perf_adjust_period() {
              if (period > 8*...) {
                  stop()
                  ...
                  start()
              }
          }
      }
      start()
}

Which caused a double start and a double stop, thus triggering
the assert in x86_pmu_start().

The patch fixes the problem by avoiding the double calls. We
pass a new argument to perf_adjust_period() to indicate whether
or not the event is already stopped. We can't just remove the
start/stop from that function because it's called from
__perf_event_overflow where the event needs to be reloaded via a
stop/start back-toback call.

The patch reintroduces the assertion in x86_pmu_start() which
was removed by commit:

	84f2b9b ("perf: Remove deprecated WARN_ON_ONCE()")

In this second version, we've added calls to disable/enable PMU
during unthrottling or frequency adjustment based on bug report
of spurious NMI interrupts from Eric Dumazet.

Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: markus@trippelsdorf.de
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/20120207133956.GA4932@quad
[ Minor edits to the changelog and to the code ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-07 16:58:56 +01:00
Linus Torvalds
14fdbf7eb4 Merge branch 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Fixing a regression with the PMU MSRs when PMU virtualization is
disabled, a guest-internal DoS with the SYSCALL instruction, and a dirty
memory logging race that may cause live migration to fail.

* 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: do not #GP on perf MSR writes when vPMU is disabled
  KVM: x86: fix missing checks in syscall emulation
  KVM: x86: extend "struct x86_emulate_ops" with "get_cpuid"
  KVM: Fix __set_bit() race in mark_page_dirty() during dirty logging
2012-02-06 16:26:58 -08:00
Stefano Stabellini
207d543f47 xen pvhvm: do not remap pirqs onto evtchns if !xen_have_vector_callback
CC: stable@kernel.org #2.6.37 and onwards
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-03 16:06:27 -05:00
Konrad Rzeszutek Wilk
41bd956de3 xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic.
When a user offlines a VCPU and then onlines it, we get:

NMI watchdog disabled (cpu2): hardware events not enabled
BUG: scheduling while atomic: swapper/2/0/0x00000002
Modules linked in: dm_multipath dm_mod xen_evtchn iscsi_boot_sysfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi scsi_mod libcrc32c crc32c radeon fbco
 ttm bitblit softcursor drm_kms_helper xen_blkfront xen_netfront xen_fbfront fb_sys_fops sysimgblt sysfillrect syscopyarea xen_kbdfront xenfs [last unloaded:

Pid: 0, comm: swapper/2 Tainted: G           O 3.2.0phase15.1-00003-gd6f7f5b-dirty #4
Call Trace:
 [<ffffffff81070571>] __schedule_bug+0x61/0x70
 [<ffffffff8158eb78>] __schedule+0x798/0x850
 [<ffffffff8158ed6a>] schedule+0x3a/0x50
 [<ffffffff810349be>] cpu_idle+0xbe/0xe0
 [<ffffffff81583599>] cpu_bringup_and_idle+0xe/0x10

The reason for this should be obvious from this call-chain:
cpu_bringup_and_idle:
 \- cpu_bringup
  |   \-[preempt_disable]
  |
  |- cpu_idle
       \- play_dead [assuming the user offlined the VCPU]
       |     \
       |     +- (xen_play_dead)
       |          \- HYPERVISOR_VCPU_off [so VCPU is dead, once user
       |          |                       onlines it starts from here]
       |          \- cpu_bringup [preempt_disable]
       |
       +- preempt_enable_no_reschedule()
       +- schedule()
       \- preempt_enable()

So we have two preempt_disble() and one preempt_enable(). Calling
preempt_enable() after the cpu_bringup() in the xen_play_dead
fixes the imbalance.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-03 16:05:42 -05:00
Stephane Eranian
84f2b9b2ed perf: Remove deprecated WARN_ON_ONCE()
With the new throttling/unthrottling code introduced with
commit:

  e050e3f0a7 ("perf: Fix broken interrupt rate throttling")

we occasionally hit two WARN_ON_ONCE() checks in:

  - intel_pmu_pebs_enable()
  - intel_pmu_lbr_enable()
  - x86_pmu_start()

The assertions are no longer problematic. There is a valid
path where they can trigger but it is harmless.

The assertion can be triggered with:

  $ perf record -e instructions:pp ....

Leading to paths:

  intel_pmu_pebs_enable
  intel_pmu_enable_event
  x86_perf_event_set_period
  x86_pmu_start
  perf_adjust_freq_unthr_context
  perf_event_task_tick
  scheduler_tick

And:

  intel_pmu_lbr_enable
  intel_pmu_enable_event
  x86_perf_event_set_period
  x86_pmu_start
  perf_adjust_freq_unthr_context.
  perf_event_task_tick
  scheduler_tick

cpuc->enabled is always on because when we get to
perf_adjust_freq_unthr_context() the PMU is not totally
disabled. Furthermore when we need to adjust a period,
we only stop the event we need to change and not the
entire PMU. Thus, when we re-enable, cpuc->enabled is
already set. Note that when we stop the event, both
pebs and lbr are stopped if necessary (and possible).

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/20120202110401.GA30911@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-03 08:24:40 +01:00
Linus Torvalds
2f2fde9272 Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', 'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bugs, x86: Fix printk levels for panic, softlockups and stack dumps

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf top: Fix number of samples displayed
  perf tools: Fix strlen() bug in perf_event__synthesize_event_type()
  perf tools: Fix broken build by defining _GNU_SOURCE in Makefile
  x86/dumpstack: Remove unneeded check in dump_trace()
  perf: Fix broken interrupt rate throttling

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW
  sched: Fix ancient race in do_exit()
  sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug
  sched/s390: Fix compile error in sched/core.c
  sched: Fix rq->nr_uninterruptible update race

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/reboot: Remove VersaLogic Menlow reboot quirk
  x86/reboot: Skip DMI checks if reboot set by user
  x86: Properly parenthesize cmpxchg() macro arguments
2012-02-02 11:11:13 -08:00
Gleb Natapov
5753785fa9 KVM: do not #GP on perf MSR writes when vPMU is disabled
Return to behaviour perf MSR had before introducing vPMU in case vPMU
is disabled. Some guests access those registers unconditionally and do
not expect it to fail.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-02-01 11:44:46 +02:00
Stephan Bärwolf
c2226fc9e8 KVM: x86: fix missing checks in syscall emulation
On hosts without this patch, 32bit guests will crash (and 64bit guests
may behave in a wrong way) for example by simply executing following
nasm-demo-application:

    [bits 32]
    global _start
    SECTION .text
    _start: syscall

(I tested it with winxp and linux - both always crashed)

    Disassembly of section .text:

    00000000 <_start>:
       0:   0f 05                   syscall

The reason seems a missing "invalid opcode"-trap (int6) for the
syscall opcode "0f05", which is not available on Intel CPUs
within non-longmodes, as also on some AMD CPUs within legacy-mode.
(depending on CPU vendor, MSR_EFER and cpuid)

Because previous mentioned OSs may not engage corresponding
syscall target-registers (STAR, LSTAR, CSTAR), they remain
NULL and (non trapping) syscalls are leading to multiple
faults and finally crashs.

Depending on the architecture (AMD or Intel) pretended by
guests, various checks according to vendor's documentation
are implemented to overcome the current issue and behave
like the CPUs physical counterparts.

[mtosatti: cleanup/beautify code]

Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-02-01 11:43:40 +02:00
Stephan Bärwolf
bdb42f5afe KVM: x86: extend "struct x86_emulate_ops" with "get_cpuid"
In order to be able to proceed checks on CPU-specific properties
within the emulator, function "get_cpuid" is introduced.
With "get_cpuid" it is possible to virtually call the guests
"cpuid"-opcode without changing the VM's context.

[mtosatti: cleanup/beautify code]

Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-02-01 11:43:33 +02:00
Michael D Labriola
e6d36a653b x86/reboot: Remove VersaLogic Menlow reboot quirk
This commit removes the reboot quirk originally added by commit
e19e074 ("x86: Fix reboot problem on VersaLogic Menlow boards").

Testing with a VersaLogic Ocelot (VL-EPMs-21a rev 1.00 w/ BIOS
6.5.102) revealed the following regarding the reboot hang
problem:

- v2.6.37 reboot=bios was needed.

- v2.6.38-rc1: behavior changed, reboot=acpi is needed,
  reboot=kbd and reboot=bios results in system hang.

- v2.6.38: VersaLogic patch (e19e074 "x86: Fix reboot problem on
  VersaLogic Menlow boards") was applied prior to v2.6.38-rc7.  This
  patch sets a quirk for VersaLogic Menlow boards that forces the use
  of reboot=bios, which doesn't work anymore.

- v3.2: It seems that commit 660e34c ("x86: Reorder reboot method
  preferences") changed the default reboot method to acpi prior to
  v3.0-rc1, which means the default behavior is appropriate for the
  Ocelot.  No VersaLogic quirk is required.

The Ocelot board used for testing can successfully reboot w/out
having to pass any reboot= arguments for all 3 current versions
of the BIOS.

Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Michael D Labriola <mlabriol@gdeb.com>
Cc: Kushal Koolwal <kushalkoolwal@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/87vcnub9hu.fsf@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-30 10:52:33 +01:00
Michael D Labriola
5955633e91 x86/reboot: Skip DMI checks if reboot set by user
Skip DMI checks for vendor specific reboot quirks if the user
passed in a reboot= arg on the command line - we should never
override user choices.

Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Michael D Labriola <mlabriol@gdeb.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/87wr8ab9od.fsf@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-30 10:52:32 +01:00
Linus Torvalds
6c334f4f6a Merge branch 'stable/for-linus-fixes-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/for-linus-fixes-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/granttable: Disable grant v2 for HVM domains.
  x86: xen: size struct xen_spinlock to always fit in arch_spinlock_t
2012-01-28 18:15:33 -08:00
Dan Carpenter
d0caf29250 x86/dumpstack: Remove unneeded check in dump_trace()
Smatch complains that we have some inconsistent NULL checking.

If "task" were NULL then it would lead to a NULL dereference
later. We can remove this test because earlier on in the
function we have:

 if (!task)
	task = current;

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Clemens Ladisch <clemens@ladisch.de>
Link: http://lkml.kernel.org/r/20120128105246.GA25092@elgon.mountain
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-28 13:09:06 +01:00
Konrad Rzeszutek Wilk
6c02b7b161 Merge commit 'v3.3-rc1' into stable/for-linus-fixes-3.3
* commit 'v3.3-rc1': (9775 commits)
  Linux 3.3-rc1
  x86, syscall: Need __ARCH_WANT_SYS_IPC for 32 bits
  qnx4: don't leak ->BitMap on late failure exits
  qnx4: reduce the insane nesting in qnx4_checkroot()
  qnx4: di_fname is an array, for crying out loud...
  KEYS: Permit key_serial() to be called with a const key pointer
  keys: fix user_defined key sparse messages
  ima: fix cred sparse warning
  uml: fix compile for x86-64
  MPILIB: Add a missing ENOMEM check
  tpm: fix (ACPI S3) suspend regression
  nvme: fix merge error due to change of 'make_request_fn' fn type
  xen: using EXPORT_SYMBOL requires including export.h
  gpio: tps65910: Use correct offset for gpio initialization
  acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec
  intel_idle: Split up and provide per CPU initialization func
  ACPI processor: Remove unneeded variable passed by acpi_processor_hotadd_init V2
  tg3: Fix single-vector MSI-X code
  openvswitch: Fix multipart datapath dumps.
  ipv6: fix per device IP snmp counters
  ...
2012-01-27 11:14:02 -05:00
Prarit Bhargava
b0f4c4b32c bugs, x86: Fix printk levels for panic, softlockups and stack dumps
rsyslog will display KERN_EMERG messages on a connected
terminal.  However, these messages are useless/undecipherable
for a general user.

For example, after a softlockup we get:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Stack:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Call Trace:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89
 d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89

This happens because the printk levels for these messages are
incorrect. Only an informational message should be displayed on
a terminal.

I modified the printk levels for various messages in the kernel
and tested the output by using the drivers/misc/lkdtm.c kernel
modules (ie, softlockups, panics, hard lockups, etc.) and
confirmed that the console output was still the same and that
the output to the terminals was correct.

For example, in the case of a softlockup we now see the much
more informative:

 Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ...
 BUG: soft lockup - CPU4 stuck for 60s!

instead of the above confusing messages.

AFAICT, the messages no longer have to be KERN_EMERG.  In the
most important case of a panic we set console_verbose().  As for
the other less severe cases the correct data is output to the
console and /var/log/messages.

Successfully tested by me using the drivers/misc/lkdtm.c module.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: dzickus@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 21:28:45 +01:00
Jan Beulich
fc395b9291 x86: Properly parenthesize cmpxchg() macro arguments
Quite oddly, all of the arguments passed through from the top
level macros to the second level which didn't need parentheses
had them, while the only expression (involving a parameter)
needing them didn't.

Very recently I got bitten by the lack thereof when using
something like "array + index" for the first operand, with
"array" being an array more narrow than int.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/4F2183A9020000780006F3E6@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 21:18:29 +01:00
Andreas Herrmann
5b68edc91c x86/microcode_amd: Add support for CPU family specific container files
We've decided to provide CPU family specific container files
(starting with CPU family 15h). E.g. for family 15h we have to
load microcode_amd_fam15h.bin instead of microcode_amd.bin

Rationale is that starting with family 15h patch size is larger
than 2KB which was hard coded as maximum patch size in various
microcode loaders (not just Linux).

Container files which include patches larger than 2KB cause
different kinds of trouble with such old patch loaders. Thus we
have to ensure that the default container file provides only
patches with size less than 2KB.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/20120120164412.GD24508@alberich.amd.com
[ documented the naming convention and tidied the code a bit. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 12:06:39 +01:00
Andreas Herrmann
652847aa44 x86/amd: Add missing feature flag for fam15h models 10h-1fh processors
That is the last one missing for those CPUs.

Others were recently added with commits

 fb215366b3
 (KVM: expose latest Intel cpu new features (BMI1/BMI2/FMA/AVX2) to guest)

and

 commit 969df4b829
 (x86: Report cpb and eff_freq_ro flags correctly)

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/20120120163823.GC24508@alberich.amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 12:06:38 +01:00
Jesper Juhl
5067cf53ca x86/boot-image: Don't leak phdrs in arch/x86/boot/compressed/misc.c::Parse_elf()
We allocate memory with malloc(), but neglect to free it before
the variable 'phdrs' goes out of scope --> leak.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1201232332590.8772@swampdragon.chaosbits.net
[ Mostly harmless. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 11:30:29 +01:00
Daniel J Blueman
3fe54564a6 x86/numachip: Drop unnecessary conflict with EDAC
EDAC detection no longer crashes multi-node systems, so don't
conflict on it with NumaChip.

Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Steffen Persvold <sp@numascale.com>
Link: http://lkml.kernel.org/r/1327473349-28395-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 11:03:03 +01:00
Cliff Wickman
d2ebc71d47 x86/uv: Fix uninitialized spinlocks
Initialize two spinlocks in tlb_uv.c and also properly define/initialize
the uv_irq_lock.

The lack of explicit initialization seems to be functionally
harmless, but it is diagnosed when these are turned on:

        CONFIG_DEBUG_SPINLOCK=y
        CONFIG_DEBUG_MUTEXES=y
        CONFIG_DEBUG_LOCK_ALLOC=y
        CONFIG_LOCKDEP=y

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/E1RnXd1-0003wU-PM@eag09.americas.sgi.com
[ Added the uv_irq_lock initialization fix by Dimitri Sivanich ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 10:58:34 +01:00
Russ Anderson
5a51467b14 x86/uv: Fix uv_gpa_to_soc_phys_ram() shift
uv_gpa_to_soc_phys_ram() was inadvertently ignoring the
shift values.  This fix takes the shift into account.

Signed-off-by: Russ Anderson <rja@sgi.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/20120119020753.GA7228@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 10:58:27 +01:00
Linus Torvalds
701b259f44 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Davem says:

1) Fix JIT code generation on x86-64 for divide by zero, from Eric Dumazet.

2) tg3 header length computation correction from Eric Dumazet.

3) More build and reference counting fixes for socket memory cgroup
   code from Glauber Costa.

4) module.h snuck back into a core header after all the hard work we
   did to remove that, from Paul Gortmaker and Jesper Dangaard Brouer.

5) Fix PHY naming regression and add some new PCI IDs in stmmac, from
   Alessandro Rubini.

6) Netlink message generation fix in new team driver, should only advertise
   the entries that changed during events, from Jiri Pirko.

7) SRIOV VF registration and unregistration fixes, and also add a
   missing PCI ID, from Roopa Prabhu.

8) Fix infinite loop in tx queue flush code of brcmsmac, from Stanislaw Gruszka.

9) ftgmac100/ftmac100 build fix, missing interrupt.h include.

10) Memory leak fix in net/hyperv do_set_mutlicast() handling, from Wei Yongjun.

11) Off by one fix in netem packet scheduler, from Vijay Subramanian.

12) TCP loss detection fix from Yuchung Cheng.

13) TCP reset packet MD5 calculation uses wrong address, fix from Shawn Lu.

14) skge carrier assertion and DMA mapping fixes from Stephen Hemminger.

15) Congestion recovery undo performed at the wrong spot in BIC and CUBIC
    congestion control modules, fix from Neal Cardwell.

16) Ethtool ETHTOOL_GSSET_INFO is unnecessarily restrictive, from Michał Mirosław.

17) Fix triggerable race in ipv6 sysctl handling, from Francesco Ruggeri.

18) Statistics bug fixes in mlx4 from Eugenia Emantayev.

19) rds locking bug fix during info dumps, from your's truly.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (67 commits)
  rds: Make rds_sock_lock BH rather than IRQ safe.
  netprio_cgroup.h: dont include module.h from other includes
  net: flow_dissector.c missing include linux/export.h
  team: send only changed options/ports via netlink
  net/hyperv: fix possible memory leak in do_set_multicast()
  drivers/net: dsa/mv88e6xxx.c files need linux/module.h
  stmmac: added PCI identifiers
  llc: Fix race condition in llc_ui_recvmsg
  stmmac: fix phy naming inconsistency
  dsa: Add reporting of silicon revision for Marvell 88E6123/88E6161/88E6165 switches.
  tg3: fix ipv6 header length computation
  skge: add byte queue limit support
  mv643xx_eth: Add Rx Discard and Rx Overrun statistics
  bnx2x: fix compilation error with SOE in fw_dump
  bnx2x: handle CHIP_REVISION during init_one
  bnx2x: allow user to change ring size in ISCSI SD mode
  bnx2x: fix Big-Endianess in ethtool -t
  bnx2x: fixed ethtool statistics for MF modes
  bnx2x: credit-leakage fixup on vlan_mac_del_all
  macvlan: fix a possible use after free
  ...
2012-01-24 15:51:40 -08:00
David Vrabel
7a7546b377 x86: xen: size struct xen_spinlock to always fit in arch_spinlock_t
If NR_CPUS < 256 then arch_spinlock_t is only 16 bits wide but struct
xen_spinlock is 32 bits.  When a spin lock is contended and
xl->spinners is modified the two bytes immediately after the spin lock
would be corrupted.

This is a regression caused by 84eb950db1
(x86, ticketlock: Clean up types and accessors) which reduced the size
of arch_spinlock_t.

Fix this by making xl->spinners a u8 if NR_CPUS < 256.  A
BUILD_BUG_ON() is also added to check the sizes of the two structures
are compatible.

In many cases this was not noticable as there would often be padding
bytes after the lock (e.g., if any of CONFIG_GENERIC_LOCKBREAK,
CONFIG_DEBUG_SPINLOCK, or CONFIG_DEBUG_LOCK_ALLOC were enabled).

The bnx2 driver is affected. In struct bnx2, phy_lock and
indirect_lock may have no padding after them.  Contention on phy_lock
would corrupt indirect_lock making it appear locked and the driver
would deadlock.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
CC: stable@kernel.org #only 3.2
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-24 12:10:19 -05:00
Linus Torvalds
567e47935a Merge branches 'sched-urgent-for-linus', 'perf-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/accounting, proc: Fix /proc/stat interrupts sum

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tracepoints/module: Fix disabling tracepoints with taint CRAP or OOT
  x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore
  x86/kprobes: Fix typo transferred from Intel manual

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, syscall: Need __ARCH_WANT_SYS_IPC for 32 bits
  x86, tsc: Fix SMI induced variation in quick_pit_calibrate()
  x86, opcode: ANDN and Group 17 in x86-opcode-map.txt
  x86/kconfig: Move the ZONE_DMA entry under a menu
  x86/UV2: Add accounting for BAU strong nacks
  x86/UV2: Ack BAU interrupt earlier
  x86/UV2: Remove stale no-resources test for UV2 BAU
  x86/UV2: Work around BAU bug
  x86/UV2: Fix BAU destination timeout initialization
  x86/UV2: Fix new UV2 hardware by using native UV2 broadcast mode
  x86: Get rid of dubious one-bit signed bitfield
2012-01-19 14:53:06 -08:00
H. Peter Anvin
4f2f81a562 x86, syscall: Need __ARCH_WANT_SYS_IPC for 32 bits
In checkin

  303395ac3b x86: Generate system call tables and unistd_*.h from tables

the feature macros in <asm/unistd.h> were unified between 32 and 64
bits.  Unfortunately 32 bits requires __ARCH_WANT_SYS_IPC and this was
inadvertently dropped.

Reported-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/CALLzPKbeXN5gdngo8uYYU8mAow=XhrwBFBhKfG811f37BubQOg@mail.gmail.com
2012-01-19 12:57:09 -08:00
H. Peter Anvin
282f445a77 Merge remote-tracking branch 'linus/master' into x86/urgent 2012-01-19 12:56:50 -08:00
Linus Torvalds
90a4c0f51e uml: fix compile for x86-64
Randy Dunlap reports that we get

  arch/x86/um/shared/sysdep/ptrace.h:7:20: error: redefinition of 'regs_return_value'
  arch/x86/um/shared/sysdep/ptrace.h:7:20: note: previous definition of 'regs_return_value' was here

when compiling UML for x86-64.

Stephen Rothwell root-caused it and says:

 "Caused by commit d7e7528bcd ("Audit: push audit success and retcode
  into arch ptrace.h") (another patch that was never in linux-next :-().

  This file now needs protection against double inclusion."

so let's do as the man says.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Analyzed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-18 19:26:11 -08:00
Linus Torvalds
507a03c1cb Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
This includes initial support for the recently published ACPI 5.0 spec.
In particular, support for the "hardware-reduced" bit that eliminates
the dependency on legacy hardware.

APEI has patches resulting from testing on real hardware.

Plus other random fixes.

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (52 commits)
  acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec
  intel_idle: Split up and provide per CPU initialization func
  ACPI processor: Remove unneeded variable passed by acpi_processor_hotadd_init V2
  ACPI processor: Remove unneeded cpuidle_unregister_driver call
  intel idle: Make idle driver more robust
  intel_idle: Fix a cast to pointer from integer of different size warning in intel_idle
  ACPI: kernel-parameters.txt : Add intel_idle.max_cstate
  intel_idle: remove redundant local_irq_disable() call
  ACPI processor: Fix error path, also remove sysdev link
  ACPI: processor: fix acpi_get_cpuid for UP processor
  intel_idle: fix API misuse
  ACPI APEI: Convert atomicio routines
  ACPI: Export interfaces for ioremapping/iounmapping ACPI registers
  ACPI: Fix possible alignment issues with GAS 'address' references
  ACPI, ia64: Use SRAT table rev to use 8bit or 16/32bit PXM fields (ia64)
  ACPI, x86: Use SRAT table rev to use 8bit or 32bit PXM fields (x86/x86-64)
  ACPI: Store SRAT table revision
  ACPI, APEI, Resolve false conflict between ACPI NVS and APEI
  ACPI, Record ACPI NVS regions
  ACPI, APEI, EINJ, Refine the fix of resource conflict
  ...
2012-01-18 15:51:48 -08:00
Eric Dumazet
d00a9dd21b net: bpf_jit: fix divide by 0 generation
Several problems fixed in this patch :

1) Target of the conditional jump in case a divide by 0 is performed
   by a bpf is wrong.

2) Must 'generate' the full function prologue/epilogue at pass=0,
   or else we can stop too early in pass=1 if the proglen doesnt change.
   (if the increase of prologue/epilogue equals decrease of all
    instructions length because some jumps are converted to near jumps)

3) Change the wrong length detection at the end of code generation to
   issue a more explicit message, no need for a full stack trace.

Reported-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-18 16:04:26 -05:00
Len Brown
79ba0db69c Merge branches 'einj', 'intel_idle', 'misc', 'srat' and 'turbostat-ivb' into release 2012-01-18 01:15:54 -05:00
Al Viro
6015ff1031 x86-32: Fix build failure with AUDIT=y, AUDITSYSCALL=n
JONGMAN HEO reports:

  With current linus git (commit a25a2b84), I got following build error,

  arch/x86/kernel/vm86_32.c: In function 'do_sys_vm86':
  arch/x86/kernel/vm86_32.c:340: error: implicit declaration of function '__audit_syscall_exit'
  make[3]: *** [arch/x86/kernel/vm86_32.o] Error 1

OK, I can reproduce it (32bit allmodconfig with AUDIT=y, AUDITSYSCALL=n)

It's due to commit d7e7528bcd: "Audit: push audit success and retcode
into arch ptrace.h".

Reported-by: JONGMAN HEO <jongman.heo@samsung.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-17 18:10:11 -08:00
Linus Torvalds
f429ee3b80 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits)
  audit: no leading space in audit_log_d_path prefix
  audit: treat s_id as an untrusted string
  audit: fix signedness bug in audit_log_execve_info()
  audit: comparison on interprocess fields
  audit: implement all object interfield comparisons
  audit: allow interfield comparison between gid and ogid
  audit: complex interfield comparison helper
  audit: allow interfield comparison in audit rules
  Kernel: Audit Support For The ARM Platform
  audit: do not call audit_getname on error
  audit: only allow tasks to set their loginuid if it is -1
  audit: remove task argument to audit_set_loginuid
  audit: allow audit matching on inode gid
  audit: allow matching on obj_uid
  audit: remove audit_finish_fork as it can't be called
  audit: reject entry,always rules
  audit: inline audit_free to simplify the look of generic code
  audit: drop audit_set_macxattr as it doesn't do anything
  audit: inline checks for not needing to collect aux records
  audit: drop some potentially inadvisable likely notations
  ...

Use evil merge to fix up grammar mistakes in Kconfig file.

Bad speling and horrible grammar (and copious swearing) is to be
expected, but let's keep it to commit messages and comments, rather than
expose it to users in config help texts or printouts.
2012-01-17 16:41:31 -08:00
Linus Torvalds
68f30fbee1 x86, tsc: Fix SMI induced variation in quick_pit_calibrate()
pit_expect_msb() returns success wrongly in the below SMI scenario:

a. pit_verify_msb() has not yet seen the MSB transition.

b. we are close to the MSB transition though and got a SMI immediately after
   returning from pit_verify_msb() which didn't see the MSB transition. PIT MSB
   transition has happened somewhere during SMI execution.

c. returned from SMI and we noted down the 'tsc', saw the pit MSB change now and
   exited the loop to calculate 'deltatsc'. Instead of noting the TSC at the MSB
   transition, we are way off because of the SMI.  And as the SMI happened
   between the pit_verify_msb() and before the 'tsc' is recorded in the
   for loop, 'delattsc' (d1/d2 in quick_pit_calibrate()) will be small and
   quick_pit_calibrate() will not notice this error.

Depending on whether SMI disturbance happens while computing d1 or d2, we will
see the TSC calibrated value smaller or bigger than the expected value. As a
result, in a cluster we were seeing a variation of approximately +/- 20MHz in
the calibrated values, resulting in NTP failures.

  [ As far as the SMI source is concerned, this is a periodic SMI that gets
    disabled after ACPI is enabled by the OS. But the TSC calibration happens
    before the ACPI is enabled. ]

To address this, change pit_expect_msb() so that

 - the 'tsc' is the TSC in between the two reads that read the MSB
change from the PIT (same as before)

 - the 'delta' is the difference in TSC from *before* the MSB changed
to *after* the MSB changed.

Now the delta is twice as big as before (it covers four PIT accesses,
roughly 4us) and quick_pit_calibrate() will loop a bit longer to get
the calibrated value with in the 500ppm precision. As the delta (d1/d2)
covers four PIT accesses, actual calibrated result might be closer to
250ppm precision.

As the loop now takes longer to stabilize, double MAX_QUICK_PIT_MS to 50.

SMI disturbance will showup as much larger delta's and the loop will take
longer than usual for the result to be with in the accepted precision. Or will
fallback to slow PIT calibration if it takes more than 50msec.

Also while we are at this, remove the calibration correction that aims to
get the result to the middle of the error bars. We really don't know which
direction to correct into, so remove it.

Reported-and-tested-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1326843337.5291.4.camel@sbsiddha-mobl2
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-01-17 15:46:51 -08:00
Eric Paris
b05d8447e7 audit: inline audit_syscall_entry to reduce burden on archs
Every arch calls:

if (unlikely(current->audit_context))
	audit_syscall_entry()

which requires knowledge about audit (the existance of audit_context) in
the arch code.  Just do it all in static inline in audit.h so that arch's
can remain blissfully ignorant.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:56 -05:00
Eric Paris
f031cd2556 audit: ia32entry.S sign extend error codes when calling 64 bit code
In the ia32entry syscall exit audit fastpath we have assembly code which calls
__audit_syscall_exit directly.  This code was, however, zeroes the upper 32
bits of the return code.  It then proceeded to call code which expects longs
to be 64bits long.  In order to handle code which expects longs to be 64bit we
sign extend the return code if that code is an error.  Thus the
__audit_syscall_exit function can correctly handle using the values in
snprintf("%ld").  This fixes the regression introduced in 5cbf1565f2.

Old record:
type=SYSCALL msg=audit(1306197182.256:281): arch=40000003 syscall=192 success=no exit=4294967283
New record:
type=SYSCALL msg=audit(1306197182.256:281): arch=40000003 syscall=192 success=no exit=-13

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
2012-01-17 16:16:56 -05:00