Commit Graph

11982 Commits

Author SHA1 Message Date
Masami Hiramatsu
cd7ebe2298 kprobes: Use text_poke_smp_batch for optimizing
Use text_poke_smp_batch() in optimization path for reducing
the number of stop_machine() issues. If the number of optimizing
probes is more than MAX_OPTIMIZE_PROBES(=256), kprobes optimizes
first MAX_OPTIMIZE_PROBES probes and kicks optimizer for
remaining probes.

Changes in v5:
- Use kick_kprobe_optimizer() instead of directly calling
  schedule_delayed_work().
- Rescheduling optimizer outside of kprobe mutex lock.

Changes in v2:
- Allocate code buffer and parameters in arch_init_kprobes()
  instead of using static arraies.
- Merge previous max optimization limit patch into this patch.
  So, this patch introduces upper limit of optimization at
  once.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20101203095428.2961.8994.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-06 17:59:31 +01:00
Masami Hiramatsu
7deb18dcf0 x86: Introduce text_poke_smp_batch() for batch-code modifying
Introduce text_poke_smp_batch(). This function modifies several
text areas with one stop_machine() on SMP. Because calling
stop_machine() is heavy task, it is better to aggregate
text_poke requests.

( Note: I've talked with Rusty about this interface, and
  he would not like to expand stop_machine() interface, since
  it is not for generic use. )

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
LKML-Reference: <20101203095422.2961.51217.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-06 17:59:31 +01:00
Masami Hiramatsu
6274de4984 kprobes: Support delayed unoptimizing
Unoptimization occurs when a probe is unregistered or disabled,
and is heavy because it recovers instructions by using
stop_machine(). This patch delays unoptimization operations and
unoptimize several probes at once by using
text_poke_smp_batch(). This can avoid unexpected system slowdown
coming from stop_machine().

Changes in v5:
- Split this patch into several cleanup patches and this patch.
- Fix some text_mutex lock miss.
- Use bool instead of int for behavior flags.
- Add additional comment for (un)optimizing path.

Changes in v2:
- Use dynamic allocated buffers and params.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
LKML-Reference: <20101203095409.2961.82733.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-06 17:59:30 +01:00
Cyrill Gorcunov
af86da5318 perf, x86: P4 PMU - describe config format
Add description of .config in a sake of RAW events.
At least this should bring some light to those who
will be reading this code.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Stephane Eranian <eranian@google.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:14:57 +01:00
Peter Zijlstra
004417a6d4 perf, arch: Cleanup perf-pmu init vs lockup-detector
The perf hardware pmu got initialized at various points in the boot,
some before early_initcall() some after (notably arch_initcall).

The problem is that the NMI lockup detector is ran from early_initcall()
and expects the hardware pmu to be present.

Sanitize this by moving all architecture hardware pmu implementations to
initialize at early_initcall() and move the lockup detector to an explicit
initcall right after that.

Cc: paulus <paulus@samba.org>
Cc: davem <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290707759.2145.119.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:14:56 +01:00
Andi Kleen
5ef428c4b5 x86: Set cpu masks before calling CPU_STARTING notifiers
When booting up a CPU set the various topology masks before
calling the CPU_STARTING notifier. This way the notifier
can actually use the masks.

This is needed for a perf change.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290077254-12165-2-git-send-email-andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:14:56 +01:00
Franck Bui-Huu
6c7e550f13 perf: Introduce is_sampling_event()
and use it when appropriate.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290525705-6265-1-git-send-email-fbuihuu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:14:54 +01:00
Ingo Molnar
6c869e772c Merge branch 'perf/urgent' into perf/core
Conflicts:
	arch/x86/kernel/apic/hw_nmi.c

Merge reason: Resolve conflict, queue up dependent patch.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:07:02 +01:00
Ingo Molnar
e4e91ac410 Merge commit 'v2.6.37-rc3' into perf/core
Merge reason: Pick up latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:04:47 +01:00
Peter Zijlstra
cc2067a514 perf, x86: Fixup Kconfig deps
This leads to a Kconfig dep inversion, x86 selects PERF_EVENT (due to
a hw_breakpoint dep) but doesn't unconditionally provide
HAVE_PERF_EVENT.

(This can cause build failures on M386/M486 kernel .config's.)

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101117222055.982965150@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:00:58 +01:00
Don Zickus
33c6d6a7ad x86, perf, nmi: Disable perf if counters are not accessible
In a kvm virt guests, the perf counters are not emulated.  Instead they
return zero on a rdmsrl. The perf nmi handler uses the fact that crossing
a zero means the counter overflowed (for those counters that do not have
specific interrupt bits). Therefore on kvm guests, perf will swallow all
NMIs thinking the counters overflowed.

This causes problems for subsystems like kgdb which needs NMIs to do its
magic. This problem was discovered by running kgdb tests.

The solution is to write garbage into a perf counter during the
initialization and hopefully reading back the same number.  On kvm
guests, the value will be read back as zero and we disable perf as
a result.

Reported-by: Jason Wessel <jason.wessel@windriver.com>
Patch-inspired-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <1290462923-30734-1-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:00:57 +01:00
Ingo Molnar
ae51ce9061 Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/core 2010-11-18 20:07:12 +01:00
Linus Torvalds
fb3ff69d13 Merge branch 'kvm-updates/2.6.37' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.37' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: Fix host userspace gsbase corruption
  KVM: Correct ordering of ldt reload wrt fs/gs reload
2010-11-18 09:45:47 -08:00
Linus Torvalds
2d42dc3feb Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  kgdb,ppc: Fix regression in evr register handling
  kgdb,x86: fix regression in detach handling
  kdb: fix crash when KDB_BASE_CMD_MAX is exceeded
  kdb: fix memory leak in kdb_main.c
2010-11-18 08:24:58 -08:00
Soeren Sandmann Pedersen
9c0729dc80 x86: Eliminate bp argument from the stack tracing routines
The various stack tracing routines take a 'bp' argument in which the
caller is supposed to provide the base pointer to use, or 0 if doesn't
have one. Since bp is garbage whenever CONFIG_FRAME_POINTER is not
defined, this means all callers in principle should either always pass
0, or be conditional on CONFIG_FRAME_POINTER.

However, there are only really three use cases for stack tracing:

(a) Trace the current task, including IRQ stack if any
(b) Trace the current task, but skip IRQ stack
(c) Trace some other task

In all cases, if CONFIG_FRAME_POINTER is not defined, bp should just
be 0.  If it _is_ defined, then

- in case (a) bp should be gotten directly from the CPU's register, so
  the caller should pass NULL for regs,

- in case (b) the caller should should pass the IRQ registers to
  dump_trace(),

- in case (c) bp should be gotten from the top of the task's stack, so
  the caller should pass NULL for regs.

Hence, the bp argument is not necessary because the combination of
task and regs is sufficient to determine an appropriate value for bp.

This patch introduces a new inline function stack_frame(task, regs)
that computes the desired bp. This function is then called from the
two versions of dump_stack().

Signed-off-by: Soren Sandmann <ssp@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@infradead.org>,
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>,
LKML-Reference: <m3oc9rop28.fsf@dhcp-100-3-82.bos.redhat.com>>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-11-18 14:37:34 +01:00
Masami Hiramatsu
de31ec8a31 x86/kprobes: Prevent kprobes to probe on save_args()
Prevent kprobes to probe on save_args() since this function
will be called from breakpoint exception handler. That will
cause infinit loop on breakpoint handling.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20101118101655.2779.2816.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18 13:40:19 +01:00
Ingo Molnar
fcf48a725a Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2010-11-18 10:37:51 +01:00
Rakib Mullick
0e2af2a9ab x86, hw_nmi: Move backtrace_mask declaration under ARCH_HAS_NMI_WATCHDOG
backtrace_mask has been used under the code context of
ARCH_HAS_NMI_WATCHDOG. So put it into that context.
We were warned by the following warning:

  arch/x86/kernel/apic/hw_nmi.c:21: warning: ‘backtrace_mask’ defined but not used

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
LKML-Reference: <1289573455-3410-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18 09:15:12 +01:00
Don Zickus
072b198a4a x86, nmi_watchdog: Remove all stub function calls from old nmi_watchdog
Now that the bulk of the old nmi_watchdog is gone, remove all
the stub variables and hooks associated with it.

This touches lots of files mainly because of how the io_apic
nmi_watchdog was implemented.  Now that the io_apic nmi_watchdog
is forever gone, remove all its fingers.

Most of this code was not being exercised by virtue of
nmi_watchdog != NMI_IO_APIC, so there shouldn't be anything to
risky here.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-3-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18 09:08:23 +01:00
Don Zickus
5f2b0ba4d9 x86, nmi_watchdog: Remove the old nmi_watchdog
Now that we have a new nmi_watchdog that is more generic and
sits on top of the perf subsystem, we really do not need the old
nmi_watchdog any more.

In addition, the old nmi_watchdog doesn't really work if you are
using the default clocksource, hpet.  The old nmi_watchdog code
relied on local apic interrupts to determine if the cpu is still
alive.  With hpet as the clocksource, these interrupts don't
increment any more and the old nmi_watchdog triggers false
postives.

This piece removes the old nmi_watchdog code and stubs out any
variables and functions calls.  The stubs are the same ones used
by the new nmi_watchdog code, so it should be well tested.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18 09:08:23 +01:00
Ingo Molnar
a89d4bd055 Merge branch 'tip/perf/urgent-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/urgent 2010-11-18 08:07:36 +01:00
Avi Kivity
c8770e7ba6 KVM: VMX: Fix host userspace gsbase corruption
We now use load_gs_index() to load gs safely; unfortunately this also
changes MSR_KERNEL_GS_BASE, which we managed separately.  This resulted
in confusion and breakage running 32-bit host userspace on a 64-bit kernel.

Fix by
- saving guest MSR_KERNEL_GS_BASE before we we reload the host's gs
- doing the host save/load unconditionally, instead of only when in guest
  long mode

Things can be cleaned up further, but this is the minmal fix for now.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-11-17 19:48:05 -02:00
Avi Kivity
0a77fe4c18 KVM: Correct ordering of ldt reload wrt fs/gs reload
If fs or gs refer to the ldt, they must be reloaded after the ldt.  Reorder
the code to that effect.

Userspace code that uses the ldt with kvm is nonexistent, so this doesn't fix
a user-visible bug.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-11-17 19:47:59 -02:00
Jason Wessel
10a6e67648 kgdb,x86: fix regression in detach handling
The fix from ba773f7c51
(x86,kgdb: Fix hw breakpoint regression) was not entirely complete.

The kgdb_remove_all_hw_break() function also needs to call the
hw_break_release_slot() or else a breakpoint can get activated again
after the debugger has detached.

The kgdb test suite exposes the behavior in the form of either a hang
or repetitive failure.  The kernel config that exposes the problem
contains all of the following:

CONFIG_DEBUG_RODATA=y
CONFIG_KGDB_TESTS=y
CONFIG_KGDB_TESTS_ON_BOOT=y
CONFIG_KGDB_TESTS_BOOT_STRING="V1F100"

Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Tested-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-11-17 13:54:57 -06:00
Arnd Bergmann
451a3c24b0 BKL: remove extraneous #include <smp_lock.h>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-17 08:59:32 -08:00
Linus Torvalds
e5c13537b0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: sysfs: fix printk warnings
  PCI: fix pci_bus_alloc_resource() hang, prefer positive decode
  PCI: read current power state at enable time
  PCI: fix size checks for mmap() on /proc/bus/pci files
  x86/PCI: coalesce overlapping host bridge windows
  PCI hotplug: ibmphp: Add check to prevent reading beyond mapped area
2010-11-15 14:01:33 -08:00
Linus Torvalds
891cbd30ef Merge branch 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen: do not release any memory under 1M in domain 0
  xen: events: do not unmask event channels on resume
  xen: correct size of level2_kernel_pgt
2010-11-12 16:01:55 -08:00
Linus Torvalds
b5c5510436 Merge branch 'stable/xen-pcifront-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/xen-pcifront-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  MAINTAINERS: Mark XEN lists as moderated
  xen-pcifront: fix PCI reference leak
  xen-pcifront: Remove duplicate inclusion of headers.
  xen: fix memory leak in Xen PCI MSI/MSI-X allocator.
  MAINTAINERS: Update mailing list name for Xen pieces.
2010-11-12 15:54:39 -08:00
Linus Torvalds
25a34554d6 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, pvclock: Remove leftover scale_delta() function
  x86, apic: Remove double #include
  x86: Adjust section annotations in AMD Fam10 MMCONF enabling code
  x86, UV: Update node controller MMRs
  x86: Remove unnecessary casts of void ptr returning alloc function return values
  x86: Address gcc4.6 "set but not used" warnings in apic.h
  x86, mm: Fix section mismatch in tlb.c
2010-11-12 08:40:23 -08:00
Frederic Weisbecker
6c0aca288e x86: Ignore trap bits on single step exceptions
When a single step exception fires, the trap bits, used to
signal hardware breakpoints, are in a random state.

These trap bits might be set if another exception will follow,
like a breakpoint in the next instruction, or a watchpoint in the
previous one. Or there can be any junk there.

So if we handle these trap bits during the single step exception,
we are going to handle an exception twice, or we are going to
handle junk.

Just ignore them in this case.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=21332

Reported-by: Michael Stefaniuc <mstefani@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>
Cc: Alexandre Julliard <julliard@winehq.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: All since 2.6.33.x <stable@kernel.org>
2010-11-12 14:51:01 +01:00
Bjorn Helgaas
4723d0f2f9 x86/PCI: coalesce overlapping host bridge windows
Some BIOSes provide PCI host bridge windows that overlap, e.g.,

    pci_root PNP0A03:00: host bridge window [mem 0xb0000000-0xffffffff]
    pci_root PNP0A03:00: host bridge window [mem 0xafffffff-0xdfffffff]
    pci_root PNP0A03:00: host bridge window [mem 0xf0000000-0xffffffff]

If we simply insert these as children of iomem_resource, the second window
fails because it conflicts with the first, and the third is inserted as a
child of the first, i.e.,

    b0000000-ffffffff PCI Bus 0000:00
      f0000000-ffffffff PCI Bus 0000:00

When we claim PCI device resources, this can cause collisions like this
if we put them in the first window:

    pci 0000:00:01.0: address space collision: [mem 0xff300000-0xff4fffff] conflicts with PCI Bus 0000:00 [mem 0xf0000000-0xffffffff]

Host bridge windows are top-level resources by definition, so it doesn't
make sense to make the third window a child of the first.  This patch
coalesces any host bridge windows that overlap.  For the example above,
the result is this single window:

    pci_root PNP0A03:00: host bridge window [mem 0xafffffff-0xffffffff]

This fixes a 2.6.34 regression.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=17011
Reported-and-tested-by: Anisse Astier <anisse@astier.eu>
Reported-and-tested-by: Pramod Dematagoda <pmd.lotr.gandalf@gmail.com>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-11-11 09:34:31 -08:00
Steven Rostedt
b590854853 tracing: Force arch_local_irq_* notrace for paravirt
When running ktest.pl randconfig tests, I would sometimes trigger
a lockdep annotation bug (possible reason: unannotated irqs-on).

This triggering happened right after function tracer self test was
executed. After doing a config bisect I found that this was caused with
having function tracer, paravirt guest, prove locking, and rcu torture
all enabled.

The rcu torture just enhanced the likelyhood of triggering the bug.
Prove locking was needed, since it was the thing that was bugging.
Function tracer would trace and disable interrupts in all sorts
of funny places.
paravirt guest would turn arch_local_irq_* into functions that would
be traced.

Besides the fact that tracing arch_local_irq_* is just a bad idea,
this is what is happening.

The bug happened simply in the local_irq_restore() code:

		if (raw_irqs_disabled_flags(flags)) {	\
			raw_local_irq_restore(flags);	\
			trace_hardirqs_off();		\
		} else {				\
			trace_hardirqs_on();		\
			raw_local_irq_restore(flags);	\
		}					\

The raw_local_irq_restore() was defined as arch_local_irq_restore().

Now imagine, we are about to enable interrupts. We go into the else
case and call trace_hardirqs_on() which tells lockdep that we are enabling
interrupts, so it sets the current->hardirqs_enabled = 1.

Then we call raw_local_irq_restore() which calls arch_local_irq_restore()
which gets traced!

Now in the function tracer we disable interrupts with local_irq_save().
This is fine, but flags is stored that we have interrupts disabled.

When the function tracer calls local_irq_restore() it does it, but this
time with flags set as disabled, so we go into the if () path.
This keeps interrupts disabled and calls trace_hardirqs_off() which
sets current->hardirqs_enabled = 0.

When the tracer is finished and proceeds with the original code,
we enable interrupts but leave current->hardirqs_enabled as 0. Which
now breaks lockdeps internal processing.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-11-10 22:29:49 -05:00
Ian Campbell
9ec23a7f6d xen: do not release any memory under 1M in domain 0
We already deliberately setup a 1-1 P2M for the region up to 1M in
order to allow code which assumes this region is already mapped to
work without having to convert everything to ioremap.

Domain 0 should not return any apparently unused memory regions
(reserved or otherwise) in this region to Xen since the e820 may not
accurately reflect what the BIOS has stashed in this region.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-11-10 17:19:25 -08:00
Peter Zijlstra
034c6efa46 perf, amd: Use kmalloc_node(,__GFP_ZERO) for northbridge structure allocation
Jasper suggested we use the zeroing capability of the allocators
instead of calling memset ourselves. Add node affinity while we're at
it.

Reported-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-10 22:58:40 +01:00
Kusanagi Kouichi
1f523bf367 x86, pvclock: Remove leftover scale_delta() function
Commit 92580d64e16402762e2acc3022f065397c780425
("x86: pvclock: Move scale_delta into common header")
forgot to remove scale_delta.

Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Cc: Zachary Amsden <zamsden@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Glauber Costa <glommer@redhat.com>
LKML-Reference: <20101105110444.BAF6D6FC03B@msa105.auone-net.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-10 10:32:15 +01:00
Jesper Juhl
2a8dcbd6cd x86, apic: Remove double #include
Remove the second <asm/atomic.h> inclusion.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
LKML-Reference: <alpine.LNX.2.00.1011072253360.26247@swampdragon.chaosbits.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-10 10:21:16 +01:00
Jan Beulich
2f62bf7d23 x86: Adjust section annotations in AMD Fam10 MMCONF enabling code
check_enable_amd_mmconf_dmi() gets called only for the BSP,
hence everything hanging off of it can be __init*.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4CD2DE1E0200007800020990@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-10 10:08:26 +01:00
Jack Steiner
62b0cfc240 x86, UV: Update node controller MMRs
A new version of the SGI UV hub node controller is being
developed. A few of the MMRs (control registers) that exist on
the current hub no longer exist on the new hub. Fortunately,
there are alternate MMRs that are are functionally equivalent
and that exist on both hubs.

This patch changes the UV code to use MMRs that exist in BOTH
versions of the hub node controller.

Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20101106204056.GA27584@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-10 10:06:38 +01:00
Jesper Juhl
8e5e9521c1 x86: Remove unnecessary casts of void ptr returning alloc function return values
The [vk][cmz]alloc(_node) family of functions return void
pointers which it's completely unnecessary/pointless to cast to
other pointer types since that happens implicitly.

This patch removes such casts from arch/x86.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: trivial@kernel.org
Cc: amd64-microcode@amd64.org
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <alpine.LNX.2.00.1011082310220.23697@swampdragon.chaosbits.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-10 09:13:00 +01:00
Andi Kleen
0059b2436a x86: Address gcc4.6 "set but not used" warnings in apic.h
native_apic_msr_read() and x2apic_enabled() use rdmsr(msr, low, high),
but only use the low part.

gcc4.6 complains about this:
.../apic.h:144:11: warning: variable 'high' set but not used [-Wunused-but-set-variable]

rdmsr() is just a wrapper around rdmsrl() which splits the 64bit value
into low and high, so using rdmsrl() directly solves this.

[tglx: Changed the variables to u64 as suggested by Cyrill. It's less
       confusing and has no code impact as this is 64bit only anyway.
       Massaged changelog as well. ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: x86@kernel.org
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <1289251229-19589-1-git-send-email-andi@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-11-09 18:40:30 +01:00
Jiri Slaby
07cf2a64c2 xen: fix memory leak in Xen PCI MSI/MSI-X allocator.
Stanse found that xen_setup_msi_irqs leaks memory when
xen_allocate_pirq fails. Free the memory in that fail path.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: xen-devel@lists.xensource.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
2010-11-08 11:30:00 -05:00
Jan Kiszka
453d9c57e2 KVM: x86: Issue smp_call_function_many with preemption disabled
smp_call_function_many is specified to be called only with preemption
disabled. Fulfill this requirement.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-11-05 14:42:27 -02:00
Vasiliy Kulikov
97e69aa62f KVM: x86: fix information leak to userland
Structures kvm_vcpu_events, kvm_debugregs, kvm_pit_state2 and
kvm_clock_data are copied to userland with some padding and reserved
fields unitialized.  It leads to leaking of contents of kernel stack
memory.  We have to initialize them to zero.

In patch v1 Jan Kiszka suggested to fill reserved fields with zeros
instead of memset'ting the whole struct.  It makes sense as these
fields are explicitly marked as padding.  No more fields need zeroing.

KVM-Stable-Tag.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-11-05 14:42:27 -02:00
Marcelo Tosatti
eb45fda45f KVM: MMU: fix rmap_remove on non present sptes
drop_spte should not attempt to rmap_remove a non present shadow pte.

This fixes a BUG_ON seen on kvm-autotest.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reported-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-11-05 14:42:26 -02:00
Michael S. Tsirkin
edde99ce05 KVM: Write protect memory after slot swap
I have observed the following bug trigger:

1. userspace calls GET_DIRTY_LOG
2. kvm_mmu_slot_remove_write_access is called and makes a page ro
3. page fault happens and makes the page writeable
   fault is logged in the bitmap appropriately
4. kvm_vm_ioctl_get_dirty_log swaps slot pointers

a lot of time passes

5. guest writes into the page
6. userspace calls GET_DIRTY_LOG

At point (5), bitmap is clean and page is writeable,
thus, guest modification of memory is not logged
and GET_DIRTY_LOG returns an empty bitmap.

The rule is that all pages are either dirty in the current bitmap,
or write-protected, which is violated here.

It seems that just moving kvm_mmu_slot_remove_write_access down
to after the slot pointer swap should fix this bug.

KVM-Stable-Tag.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-11-05 14:42:25 -02:00
Rakib Mullick
cf38d0ba7e x86, mm: Fix section mismatch in tlb.c
Mark tlb_cpuhp_notify as __cpuinit. It's basically a callback
function, which is called from __cpuinit init_smp_flash(). So -
it's safe.

We were warned by the following warning:

 WARNING: arch/x86/mm/built-in.o(.text+0x356d): Section mismatch
 in reference from the function tlb_cpuhp_notify() to the
 function .cpuinit.text:calculate_tlb_offset()
 The function tlb_cpuhp_notify() references
 the function __cpuinit calculate_tlb_offset().
 This is often because tlb_cpuhp_notify lacks a __cpuinit
 annotation or the annotation of calculate_tlb_offset is wrong.

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Shaohua Li <shaohua.li@intel.com>
LKML-Reference: <AANLkTinWQRG=HA9uB3ad0KAqRRTinL6L_4iKgF84coph@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-01 10:09:07 +01:00
Linus Torvalds
f02a38d86a Merge branches 'perf-fixes-for-linus' and 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  jump label: Add work around to i386 gcc asm goto bug
  x86, ftrace: Use safe noops, drop trap test
  jump_label: Fix unaligned traps on sparc.
  jump label: Make arch_jump_label_text_poke_early() optional
  jump label: Fix error with preempt disable holding mutex
  oprofile: Remove deprecated use of flush_scheduled_work()
  oprofile: Fix the hang while taking the cpu offline
  jump label: Fix deadlock b/w jump_label_mutex vs. text_mutex
  jump label: Fix module __init section race

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Check irq_remapped instead of remapping_enabled in destroy_irq()
2010-10-30 11:43:26 -07:00
Yinghai Lu
7b79462a20 x86: Check irq_remapped instead of remapping_enabled in destroy_irq()
Russ Anderson reported:
| There is a regression that is causing a NULL pointer dereference
| in free_irte when shutting down xpc. git bisect narrowed it down
| to git commit d585d06(intr_remap: Simplify the code further), which
| changed free_irte(). Reverse applying the patch fixes the problem.

We need to use irq_remapped() for each irq instead of checking only
intr_remapping_enabled as there might be non remapped irqs even when
remapping is enabled.

[ tglx: use cfg instead of retrieving it again. Massaged changelog ]

Reported-bisected-and-tested-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4CCBD511.40607@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-10-30 10:28:31 +02:00
Linus Torvalds
2d10d8737c Merge branches 'x86-fixes-for-linus' and 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, alternative: Call stop_machine_text_poke() on all cpus
  x86-32: Restore irq stacks NUMA-aware allocations
  x86, memblock: Fix early_node_mem with big reserved region.

* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, uv: More Westmere support on SGI UV
  x86, uv: Enable Westmere support on SGI UV
2010-10-29 18:58:00 -07:00
Jason Baron
404ba5d7bb x86, alternative: Call stop_machine_text_poke() on all cpus
Currently, text_poke_smp() passes a NULL as the third argument to
__stop_machine(), which will only run stop_machine_text_poke()
on 1 cpu. Change NULL -> cpu_online_mask, as stop_machine_text_poke()
is intended to be run on all cpus.

I actually didn't notice any problems with stop_machine_text_poke()
only being called on 1 cpu, but found this via code inspection.

Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <20101028152026.GB2875@redhat.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-10-29 16:42:58 -07:00