Commit Graph

426 Commits

Author SHA1 Message Date
Peter Zijlstra fb1dac909d lockdep: more hardirq annotations for notify_die()
On Sat, 2007-12-29 at 18:06 +0100, Marcin Slusarz wrote:
> Hi
> Today I've got this (while i was upgrading my gentoo box):
>
> WARNING: at kernel/lockdep.c:2658 check_flags()
> Pid: 21680, comm: conftest Not tainted 2.6.24-rc6 #63
>
> Call Trace:
>  [<ffffffff80253457>] check_flags+0x1c7/0x1d0
>  [<ffffffff80257217>] lock_acquire+0x57/0xc0
>  [<ffffffff8024d5c0>] __atomic_notifier_call_chain+0x60/0xd0
>  [<ffffffff8024d641>] atomic_notifier_call_chain+0x11/0x20
>  [<ffffffff8024d67e>] notify_die+0x2e/0x30
>  [<ffffffff8020da0a>] do_divide_error+0x5a/0xa0
>  [<ffffffff80522bdd>] trace_hardirqs_on_thunk+0x35/0x3a
>  [<ffffffff80255b89>] trace_hardirqs_on+0xd9/0x180
>  [<ffffffff80522bdd>] trace_hardirqs_on_thunk+0x35/0x3a
>  [<ffffffff80523c2d>] error_exit+0x0/0xa9
>
> possible reason: unannotated irqs-off.
> irq event stamp: 4693
> hardirqs last  enabled at (4693): [<ffffffff80522bdd>] trace_hardirqs_on_thunk+0x35/0x3a
> hardirqs last disabled at (4692): [<ffffffff80522c17>] trace_hardirqs_off_thunk+0x35/0x37
> softirqs last  enabled at (3546): [<ffffffff80238343>] __do_softirq+0xb3/0xd0
> softirqs last disabled at (3521): [<ffffffff8020c97c>] call_softirq+0x1c/0x30

more early fixups for notify_die()..

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-16 09:51:59 +01:00
Bernhard Walle 8ee291f87c x86: fix RTC_AIE with CONFIG_HPET_EMULATE_RTC
In the current code, RTC_AIE doesn't work if the RTC relies on
CONFIG_HPET_EMULATE_RTC because the code sets the RTC_AIE flag in
hpet_set_rtc_irq_bit().  The interrupt handles does accidentally check
for RTC_PIE and not RTC_AIE when comparing the time which was set in
hpet_set_alarm_time().

I now verified on a test system here that without the patch applied,
the attached test program fails on a system that has HPET with
2.6.24-rc7-default. That's not critical since I guess the problem has
been there for several kernel releases, but as the fix is quite
obvious.

Configuration is CONFIG_RTC=y and CONFIG_HPET_EMULATE_RTC=y.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-15 16:44:38 +01:00
Ingo Molnar 23be8c7ddf x86: fix boot crash on HIGHMEM4G && SPARSEMEM
Denys Fedoryshchenko reported a bootup crash when he upgraded
his system from 3GB to 4GB RAM:

   http://lkml.org/lkml/2008/1/7/9

the bug is due to HIGHMEM4G && SPARSEMEM kernels making pfn_to_page()
to return an invalid pointer when the pfn is in a memory hole. The
256 MB PCI aperture at the end of RAM was not mapped by sparsemem,
and hence the pfn was not valid. But set_highmem_pages_init() iterated
this range without checking the pfn's validity first.

this bug was probably present in the sparsemem code ever since sparsemem
has been introduced in v2.6.13. It was masked due to HIGHMEM64G using
larger memory regions in sparsemem_32.h:

 #ifdef CONFIG_X86_PAE
 #define SECTION_SIZE_BITS       30
 #define MAX_PHYSADDR_BITS       36
 #define MAX_PHYSMEM_BITS        36
 #else
 #define SECTION_SIZE_BITS       26
 #define MAX_PHYSADDR_BITS       32
 #define MAX_PHYSMEM_BITS        32
 #endif

which creates 1GB sparsemem regions instead of 64MB sparsemem regions.
So in practice we only ever created true sparsemem holes on x86 with
HIGHMEM4G - but that was rarely used by distros.

( btw., we could probably save 2MB of mem_map[]s on X86_PAE if we reduced
  the sparsemem region size to 256 MB. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-15 16:44:37 +01:00
Steven Rostedt 40d6a14662 Kick CPUS that might be sleeping in cpus_idle_wait
Sometimes cpu_idle_wait gets stuck because it might miss CPUS that are
already in idle, have no tasks waiting to run and have no interrupts going
to them.  This is common on bootup when switching cpu idle governors.

This patch gives those CPUS that don't check in an IPI kick.

 Background:
 -----------
I notice this while developing the mcount patches, that every once in a
while the system would hang. Looking deeper, the hang was always at boot
up when registering init_menu of the cpu_idle menu governor. Talking
with Thomas Gliexner, we discovered that one of the CPUS had no timer
events scheduled for it and it was in idle (running with NO_HZ). So the
CPU would not set the cpu_idle_state bit.

Hitting sysrq-t a few times would eventually route the interrupt to the
stuck CPU and the system would continue.

Note, I would have used the PDA isidle but that is set after the
cpu_idle_state bit is cleared, and would leave a window open where we
may miss being kicked.

hmm, looking closer at this, we still have a small race window between
clearing the cpu_idle_state and disabling interrupts (hence the RFC).

    CPU0:                          CPU 1:
  ---------                       ---------
 cpu_idle_wait():                 cpu_idle():
      |                           __cpu_cpu_var(is_idle) = 1;
      |                           if (__get_cpu_var(cpu_idle_state)) /* == 0 */
 per_cpu(cpu_idle_state, 1) = 1;         |
 if (per_cpu(is_idle, 1)) /* == 1 */     |
 smp_call_function(1)                    |
      |                             receives ipi and runs do_nothing.
 wait on map == empty               idle();
   /* waits forever */

So really we need interrupts off for most of this then. One might think
that we could simply clear the cpu_idle_state from do_nothing, but I'm
assuming that cpu_idle governors can be removed, and this might cause a
race that a governor might be used after the module was removed.

Venki said:

  I think your RFC patch is the right solution here.  As I see it, there is
  no race with your RFC patch.  As long as you call a dummy smp_call_function
  on all CPUs, we should be OK.  We can get rid of cpu_idle_state and the
  current wait forever logic altogether with dummy smp_call_function.  And so
  there wont be any wait forever scenario.

  The whole point of cpu_idle_wait() is to make all CPUs come out of idle
  loop atleast once.  The caller will use cpu_idle_wait something like this.

  // Want to change idle handler

  - Switch global idle handler to always present default_idle

  - call cpu_idle_wait so that all cpus come out of idle for an instant
    and stop using old idle pointer and start using default idle

  - Change the idle handler to a new handler

  - optional cpu_idle_wait if you want all cpus to start using the new
    handler immediately.

Maybe the below 1s patch is safe bet for .24.  But for .25, I would say we
just replace all complicated logic by simple dummy smp_call_function and
remove cpu_idle_state altogether.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-14 08:52:22 -08:00
Len Brown 02d5bccf8e Pull bugzilla-9194 into release branch 2008-01-11 12:27:13 -05:00
Len Brown 9f9adecd2d PM: ACPI and APM must not be enabled at the same time
ACPI and APM used "pm_active" to guarantee that
they would not be simultaneously active.

But pm_active was recently moved under CONFIG_PM_LEGACY,
so that without CONFIG_PM_LEGACY, pm_active became a NOP --
allowing ACPI and APM to both be simultaneously enabled.
This caused unpredictable results, including boot hangs.

Further, the code under CONFIG_PM_LEGACY is scheduled
for removal.

So replace pm_active with pm_flags.
pm_flags depends only on CONFIG_PM,
which is present for both CONFIG_APM and CONFIG_ACPI.

http://bugzilla.kernel.org/show_bug.cgi?id=9194

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2008-01-11 12:26:47 -05:00
Thomas Gleixner a2b484a29c x86: fix do_fork_idle section mismatch
With CPU_HOTPLUG=n:

WARNING: vmlinux.o(.text+0x104f8): Section mismatch: reference to .init.text:fork_idle (between
'do_fork_idle' and 'lapic_timer_broadcast')

do_fork_idle() needs to be __cpuinit. It can be static as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-08 16:10:35 -08:00
Rusty Russell 476c6c11a9 fix lguest rmmod "bad pgd"
After 17d57a9206 ("x86: fix x86-32 early
fixmap initialization.") removing lg.ko caused a printk from vunmap:

	mm/memory.c:115: bad pgd 004b3027.

On the second use after module load, the kernel crashes.

This fixes the immediate problem (accessed and dirty bits not set as
expected in pmd_none_or_clear_bad).  I can't see why this would cause
a crash, but I haven't been able to reproduce it once this is applied.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-01 11:30:35 -08:00
Linus Torvalds 0068441870 Revert "x86: fix show cpuinfo cpu number always zero"
This reverts commit fbdcf18df7.

As pointed out by Yanmin Zhang, the problem was already fixed
differently (and correctly), and rather than fix anything, it actually
causes us to create a sub-optimal sched-domains hierarchy (not setting
up the domain belonging to the core) when CONFIG_X86_HT=y.

Requested-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-25 20:16:16 -08:00
Jason Gaston 04fa11ea17 x86: intel_cacheinfo.c: cpu cache info entry for Intel Tolapai
This patch adds a cpu cache info entry for the Intel Tolapai cpu.

Signed-off-by: Jason Gaston <jason.d.gaston@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-21 01:27:19 +01:00
Ingo Molnar c0a698b744 x86: fix die() to not be preemptible
Andrew "Eagle Eye" Morton noticed that we use raw_local_save_flags()
instead of raw_local_irq_save(flags) in die(). This allows the
preemption of oopsing contexts - which is highly undesirable. It also
causes CONFIG_DEBUG_PREEMPT to complain, as reported by Miles Lane.

this bug was introduced via:

  commit 39743c9ef7
  Author: Andi Kleen <ak@suse.de>
  Date:   Fri Oct 19 20:35:03 2007 +0200

      x86: use raw locks during oopses

-               spin_lock_irqsave(&die.lock, flags);
+               __raw_spin_lock(&die.lock);
+               raw_local_save_flags(flags);

that is not a correct open-coding of spin_lock_irqsave(): both the
ordering is wrong (irqs should be disabled _first_), and the wrong
flags-saving API was used.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-12-21 01:27:19 +01:00
Mike Travis fbdcf18df7 x86: fix show cpuinfo cpu number always zero
when called by setup_arch) after smp_store_cpu_info() had set it to the
correct value.

The error shows up in 'cat /proc/cpuinfo' will all cpus = 0.

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Suresh B Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-19 23:20:19 +01:00
Adrian Bunk 3d054f0fad x86_32: disable_pse must be __cpuinitdata
CONFIG_HOTPLUG_CPU=y:

WARNING: vmlinux.o(.text+0xfa52): Section mismatch: reference to .init.data:disable_pse (between 'identify_cpu' and 'identify_secondary_cpu')

[ akpm@linux-foundation.org: initializer fix. ]

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-19 23:20:19 +01:00
Adrian Bunk 3446fa057c x86_32: select_idle_routine() must be __cpuinit
CONFIG_HOTPLUG_CPU=y:

WARNING: vmlinux.o(.text+0x1199a): Section mismatch: reference to .init.text.5:select_idle_routine (between 'init_intel' and 'init_nexgen')

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-19 23:20:18 +01:00
Adrian Bunk f2206ec92c x86 smpboot_32.c section fixes
CONFIG_HOTPLUG_CPU=y:

WARNING: vmlinux.o(.text+0x22c60): Section mismatch: reference to .init.data:cpu_idle_tasks (between 'do_boot_cpu' and 'do_warm_boot_cpu')
WARNING: vmlinux.o(.text+0x22c99): Section mismatch: reference to .init.data:cpu_idle_tasks (between 'do_boot_cpu' and 'do_warm_boot_cpu')
WARNING: vmlinux.o(.text+0x2359b): Section mismatch: reference to .init.data:smp_b_stepping (between 'smp_store_cpu_info' and 'cpu_exit_clear')
WARNING: vmlinux.o(.text+0x235a0): Section mismatch: reference to .init.data:smp_b_stepping (between 'smp_store_cpu_info' and 'cpu_exit_clear')

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-19 23:20:18 +01:00
Adrian Bunk d533798326 x86 apic_32.c section fix
CONFIG_HOTPLUG_CPU=y:

WARNING: vmlinux.o(.text+0x2390d): Section mismatch: reference to .init.text.5:setup_local_APIC (between 'start_secondary' and 'check_tsc_warp')

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-19 23:20:18 +01:00
Ingo Molnar 4aae070252 x86: fix "Kernel panic - not syncing: IO-APIC + timer doesn't work!"
this is the tale of a full day spent debugging an ancient but elusive bug.

after booting up thousands of random .config kernels, i finally happened
to generate a .config that produced the following rare bootup failure
on 32-bit x86:

| ..TIMER: vector=0x31 apic1=0 pin1=2 apic2=-1 pin2=-1
| ..MP-BIOS bug: 8254 timer not connected to IO-APIC
| ...trying to set up timer (IRQ0) through the 8259A ...  failed.
| ...trying to set up timer as Virtual Wire IRQ... failed.
| ...trying to set up timer as ExtINT IRQ... failed :(.
| Kernel panic - not syncing: IO-APIC + timer doesn't work!  Boot with apic=debug
| and send a report.  Then try booting with the 'noapic' option

this bug has been reported many times during the years, but it was never
reproduced nor fixed.

the bug that i hit was extremely sensitive to .config details.

First i did a .config-bisection - suspecting some .config detail.
That led to CONFIG_X86_MCE: enabling X86_MCE magically made the bug disappear
and the system would boot up just fine.

Debugging my way through the MCE code ended up identifying two unlikely
candidates: the thing that made a real difference to the hang was that
X86_MCE did two printks:

 Intel machine check architecture supported.
 Intel machine check reporting enabled on CPU#1.

Adding the same printks to a !CONFIG_X86_MCE kernel made the bug go away!

this left timing as the main suspect: i experimented with adding various
udelay()s to the arch/x86/kernel/io_apic_32.c:check_timer() function, and
the race window turned out to be narrower than 30 microseconds (!).

That made debugging especially funny, debugging without having printk
ability before the bug hits is ... interesting ;-)

eventually i started suspecting IRQ activities - those are pretty much the
only thing that happen this early during bootup and have the timescale of
a few dozen microseconds. Also, check_timer() changes the IRQ hardware
in various creative ways, so the main candidate became IRQ0 interaction.

i've added a counter to track timer irqs (on which core they arrived, at
what exact time, etc.) and found that no timer IRQ would arrive after the
bug condition hits - even if we re-enable IRQ0 and re-initialize the i8259A,
but that we'd get a small number of timer irqs right around the time when we
call the check_timer() function.

Eventually i got the following backtrace triggered from debug code in the
timer interrupt:

...trying to set up timer as Virtual Wire IRQ... failed.
...trying to set up timer as ExtINT IRQ...
Pid: 1, comm: swapper Not tainted (2.6.24-rc5 #57)
EIP: 0060:[<c044d57e>] EFLAGS: 00000246 CPU: 0
EIP is at _spin_unlock_irqrestore+0x5/0x1c
EAX: c0634178 EBX: 00000000 ECX: c4947d63 EDX: 00000246
ESI: 00000002 EDI: 00010031 EBP: c04e0f2e ESP: f7c41df4
 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
 CR0: 8005003b CR2: ffe04000 CR3: 00630000 CR4: 000006d0
 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
 DR6: ffff0ff0 DR7: 00000400
  [<c05f5784>] setup_IO_APIC+0x9c3/0xc5c

the spin_unlock() was called from init_8259A(). Wait ... we have an IRQ0
entry while we are in the middle of setting up the local APIC, the i8259A
and the PIT??

That is certainly not how it's supposed to work! check_timer() was supposed
to be called with irqs turned off - but this eroded away sometime in the
past. This code would still work most of the time because this code runs
very quickly, but just the right timing conditions are present and IRQ0
hits in this small, ~30 usecs window, timer irqs stop and the system does
not boot up. Also, given how early this is during bootup, the hang is
very deterministic - but it would only occur on certain machines (and
certain configs).

The fix was quite simple: disable/restore interrupts properly in this
function. With that in place the test-system now boots up just fine.

(64-bit x86 io_apic_64.c had the same bug.)

Phew! One down, only 1500 other kernel bugs are left ;-)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-18 18:05:58 +01:00
Masami Hiramatsu 0b0122faf4 x86: kprobes bugfix
Kprobes for x86-64 may cause a kernel crash if it inserted on "iret"
instruction. "call absolute" is invalid on x86-64, so we don't need
treat it.

 - Change the processing order as same as x86-32.
 - Add "iret"(0xcf) case.
 - Remove next_rip local variable.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-18 18:05:58 +01:00
Masami Hiramatsu 29b6cd794e x86: jprobe bugfix
jprobe for x86-64 may cause kernel page fault when the jprobe_return()
is called from incorrect function.

- Use jprobe_saved_regs instead getting it from stack.
  (Especially on x86-64, it may get incorrect data, because
   pt_regs can not be get by using container_of(rsp))
- Change the type of stack pointer to unsigned long *.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-18 18:05:58 +01:00
Barry Kasindorf bd87f1f028 oprofile: op_model_athlon.c support for AMD family 10h barcelona performance counters
This patch is for controlling the upper 32bits of the event ctrl msrs.
This includes the upper 4 bits of the event select and the Guest Only and
Host Only bits

This patch is necessary to make Event Based Profiling work reliably on a
Family 10h processor

[akpm@linux-foundation.org: checkpatch.pl fixes]

Signed-off-by: Barry Kasindorf <barry.kasindorf@amd.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-18 18:05:58 +01:00
Andrew Morton 5867a78f41 revert "Hibernation: Use temporary page tables for kernel text mapping on x86_64"
Revert commit efa4d2fb04 ("Hibernation:
Use temporary page tables for kernel text mapping on x86_64") because it
causes my t61p to reboot right at the end of resume-from-disk.  For
reasons unknown at this time.

Cc: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17 19:28:15 -08:00
Jeremy Fitzhardinge 7999f4b4e5 xen: relax signature check
Some versions of Xen 3.x set their magic number to "xen-3.[12]", so
relax the test to match them.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-10 19:46:58 -08:00
Len Brown f7a5274d7d Pull suspend-2.6.24 into release branch 2007-12-06 16:26:52 -05:00
Pavel Machek 74d0f3338f ACPI: suspend: old debugging hacks sneaked back
Old debugging hack sneaked back during x86 merge, this removes it.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2007-12-06 16:03:06 -05:00
Linus Torvalds 3743d33edf Tiny clean-up of OPROFILE/KPROBES configuration
Make the Kconfig.instrumentation file a bit easier on the eyes, and use
the new ARCH_SUPPORTS_OPROFILE for x86[-64].

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-06 09:41:12 -08:00
Andrew Morton da54becc71 x86: arch_register_cpu() section fix
fix this on i386 allnoconfig:

 WARNING: vmlinux.o(.text+0x6f2e): Section mismatch: reference to .init.text:register_cpu (between 'arch_register_cpu' and 'text_poke')

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-04 17:19:07 +01:00
Adrian Bunk f22d9bc1e8 x86: free_cache_attributes() section fix
free_cache_attributes() must be __cpuinit since it calls the
__cpuinit cache_remove_shared_cpu_map().

This patch fixes the following section mismatch reported by
Chris Clayton:

 ...
 WARNING: vmlinux.o(.text+0x90b6): Section mismatch: reference to .init.text:cache_remove_shared_cpu_map (between 'free_cache_attributes' and 'show_level')
 ...

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-04 17:19:07 +01:00
Don Zickus 75bc122c2d x86: add the word 'WARNING' in check_nmi_watchdog() output
Our automated test suite looks for keywords like error, fail, warning in
the boot log.  In the case when the nmi watchdog is determined to be
stuck in check_nmi_watchdog(), none of those keywords are displayed.

This patch adds a keyword, "WARNING:", so it makes it easier to notice
when the nmi watchdog isn't working correctly. Also add a proper
KERN_WARNING mark to this printout.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-04 17:19:07 +01:00
Adrian Bunk ee0011a798 x86: revert CONFIG_X86_HT semantics change
The recent Kconfig changes in x86 resulted in CONFIG_X86_HT no longer
being set if (X86_32 && MK8).

After grep'ing through the tree I think the problem is that different
places have different assumptions about the semantics of CONFIG_X86_HT,
either:

- hyperthreading or
- multicore

This should be sorted out properly, but until then we should keep the
2.6.23 status quo.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-04 17:19:07 +01:00
Eric W. Biederman 17d57a9206 x86: fix x86-32 early fixmap initialization.
pageexec@freemail.hu writes:

> i've just noticed that the chunk in i386/kernel/head.S ended up in a
> weird place, namely, it's not going to be executed as it's just after
> a 'jmp 3f' and before startup_32_smp, probably not what you intended.
> on a sidenote, the whole thing can be done in a single insn, like:
>
> movl $(swapper_pg_pmd - __PAGE_OFFSET + 0x067), (swapper_pg_dir -
> __PAGE_OFFSET+ 4092)

Thanks for the reminder I thought we had fixed this problem a while ago.

Needed to get fixed virtual address for USB debug and earlycon with mmio.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-12-03 17:17:10 +01:00
OGAWA Hirofumi 0c1b272406 x86: disable hpet legacy replacement for kdump
we should also add hpet_disable() for kdump.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-03 17:17:10 +01:00
OGAWA Hirofumi c86c7fbc82 x86: disable hpet on shutdown
If HPET was enabled by pci quirks, we use i8253 as initial clockevent
because pci quirks doesn't run until pci is initialized.

The above means the kernel (or something) is assuming HPET legacy
replacement is disabled and can use i8253 at boot.

If we used kexec, it isn't true. So, this patch disables HPET legacy
replacement for kexec in machine_shutdown().

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-03 17:17:10 +01:00
Linus Torvalds e1cca7e8d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup:
  x86 setup: don't recalculate ss:esp unless really necessary
2007-11-29 16:25:29 -08:00
Jeremy Fitzhardinge f97b895495 x86/paravirt: revert exports to restore old behaviour
Subdividing the paravirt_ops structure caused a regression in certain
non-GPL modules which try to use mmu_ops and cpu_ops.  This restores the
old behaviour, and makes it consistent with the non-CONFIG_PARAVIRT case.

Takashi Iwai <tiwai@suse.de> adds:
> I took at this problem (as I have an nvidia card on one of my
> workstations), and found out that the following suffer from
> EXPORT_SYMBOL_GPL changes:
>
> * local_disable_irq(), local_irq_save*(), etc.
> * MSR-related macros like rdmsr(), wrmsr(), read_cr0(), etc.
>   wbinvd(), too.
> * pmd_val(), pgd_val(), etc are all involved with pv_mm_ops.
>   pmd_large() and pmd_bad() is also indirectly involved.
>   __flush_tlb() and friends suffer, too.

Christoph Hellwig objects to this patch on the grounds that modules
shouldn't be using these operations anyway.  I don't think this is a
particularly good reason to reject the patch, for several reasons:

1. These operations are still available to modules when not using
   CONFIG_PARAVIRT, since they are implicitly exported as inline
   functions via the kernel headers.  Exporting the same functionality as
   GPL-only symbols just adds a gratuitious difference between
   CONFIG_PARAVIRT and non-CONFIG_PARAVIRT configurations.  If we really
   think these operations are not for module use (or non-GPL module use),
   then we should solve the problem in a general way.

2. It's a regression from previous kernels, which would work these
   modules even with CONFIG_PARAVIRT enabled.

3. The operations in question seem pretty reasonable for modules to
   use.  The control registers/MSRs can be accessed directly anyway, so there's
   no benefit in preventing modules from using standard interfaces.  And it seems
   reasonable to allow a graphics driver to create its own mappings if it wants.

Therefore, I think this patch should go in for 2.6.24.  If people
really think that these operations should not be available to modules,
then we can address that separately.

Signed-off-by: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Cc: Tobias Powalowski <t.powa@gmx.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:55 -08:00
Randy Dunlap b8415ec34f lguest: prevent VISWS or VOYAGER randconfigs
Keep lguest from being enabled on VISWS or VOYAGER configs, just as is
already done for VMI and XEN.  Otherwise randconfigs with VISWS and LGUEST
have this problem:

In file included from arch/x86/kernel/setup_32.c:61:
include/asm-x86/mach-visws/setup_arch.h:8:1: warning: "ARCH_SETUP" redefined
In file included from include/asm/msr.h:80,
                 from include/asm/processor_32.h:17,
                 from include/asm/processor.h:2,
                 from include/asm/thread_info_32.h:16,
                 from include/asm/thread_info.h:2,
                 from include/linux/thread_info.h:21,
                 from include/linux/preempt.h:9,
                 from include/linux/spinlock.h:49,
                 from include/linux/seqlock.h:29,
                 from include/linux/time.h:8,
                 from include/linux/timex.h:57,
                 from include/linux/sched.h:53,
                 from arch/x86/kernel/setup_32.c:24:
include/asm/paravirt.h:458:1: warning: this is the location of the previous definition

(and of course, this happens because kconfig does not follow dependencies
when [evil] select is used...)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:55 -08:00
KAMEZAWA Hiroyuki b6fd6ecb83 memory hotplug x86_64: fix section mismatch in init_memory_mapping()
Changes __meminit to __init_refok.

WARNING: vmlinux.o(.text+0x1d07c): Section mismatch: reference to
.init.text:find_e820_area (between 'init_memory_mapping' and 'arch_add_memory')

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:54 -08:00
Jeremy Fitzhardinge 2c80b01bea xen: mask _PAGE_PCD from ptes
_PAGE_PCD maps a page with caching disabled, which is typically used for
mapping harware registers.  Xen never allows it to be set on a mapping, and
unprivileged guests never need it since they can't see the real underlying
hardware.  However, some uncached mappings are made early when probing the
(non-existent) APIC, and its OK to mask off the PCD flag in these cases.

This became necessary because Xen started checking for this bit, rather
than silently masking it off.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:52 -08:00
Jens Rottmann 16252da654 x86 setup: don't recalculate ss:esp unless really necessary
In order to work around old LILO versions providing an invalid ss
register, the current setup code always sets up a new stack,
immediately following .bss and the heap. But this breaks LOADLIN.

This rewrite of the workaround checks for an invalid stack (ss!=ds)
first, and leaves ss:sp alone otherwise (apart from aligning esp).

[hpa note: LOADLIN has a number of arbitrary hard-coded limits that
are being pushed up against.  Without some major revision of LOADLIN
itself it will not be sustainable keeping it alive.  This gives it
another brief lease on life, however.  This patch also helps the
cmdline truncation problem with old versions of SYSLINUX.]

Signed-off-by: Jens Rottmann <JRottmann at LiPPERT-AT. de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2007-11-28 18:17:17 -08:00
Linus Torvalds ff1ea52fa3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
* git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86:
  x86: fix APIC related bootup crash on Athlon XP CPUs
  time: add ADJ_OFFSET_SS_READ
  x86: export the symbol empty_zero_page on the 32-bit x86 architecture
  x86: fix kprobes_64.c inlining borkage
  pci: use pci=bfsort for HP DL385 G2, DL585 G2
  x86: correctly set UTS_MACHINE for "make ARCH=x86"
  lockdep: annotate do_debug() trap handler
  x86: turn off iommu merge by default
  x86: fix ACPI compile for LOCAL_APIC=n
  x86: printk kernel version in WARN_ON and other dump_stack users
  ACPI: Set max_cstate to 1 for early Opterons.
  x86: fix NMI watchdog & 'stopped time' problem
2007-11-26 19:41:28 -08:00
Linus Torvalds 6b41016032 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (39 commits)
  ACPI: EC: Workaround for optimized controllers (version 3)
  ACPI: EC: use printk_ratelimit(), add some DEBUG mode messages
  Revert "ACPI: EC: Workaround for optimized controllers"
  ACPI: fix two IRQ8 issues in IOAPIC mode
  ACPI: Add missing spaces to printk format
  cpuidle: fix HP nx6125 regression
  cpuidle: add sched_clock_idle_[sleep|wakeup]_event() hooks
  cpuidle: fix C3 for no bus-master control case
  ACPI: thinkpad-acpi: fix oops when a module parameter has no value
  Revert "Fix very high interrupt rate for IRQ8 (rtc) unless pnpacpi=off"
  ACPI: EC: Don't init EC early if it has no _INI
  Revert "acpi: make ACPI_PROCFS default to y"
  Revert "ACPI: add documentation for deprecated /proc/acpi/battery in ACPI_PROCFS"
  ACPI: Split out control for /proc/acpi entries from battery, ac, and sbs.
  ACPI: Video: Increase buffer size for writes to brightness proc file.
  ACPI: EC: Workaround for optimized controllers
  ACPI: SBS: Fix retval warning
  ACPI: Enable MSR (FixedHW) support for T-States
  ACPI: Get throttling info from BIOS only after evaluating _PDC
  ACPI: Use _TSS for throttling control, when present. Add error checks.
  ...
2007-11-26 19:09:58 -08:00
Andreas Herrmann 8c6531f7a9 x86: correctly set UTS_MACHINE for "make ARCH=x86"
For a kernel built with "make ARCH=x86" the following system
information is displayed when running the new kernel

    $ uname -m
    x86

On some i386 systems (e.g. K7) we even have the following information

    $ uname -m
    x66

This is weird. The usual information for "uname -m" should be "x86_64"
on 64-bit and "i386" or "i686" on 32-bit.

This patch fixes the issue by setting UTS_MACHINE to "i386" for 32-bit
kernel builds and to "x86_64" for 64-bit kernel builds. I.e., "x86"
won't be used for UTS_MACHINE anymore.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andreas Herrmann <aherrman@arcor.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-26 17:38:53 -08:00
Ingo Molnar f44d9efd35 x86: fix APIC related bootup crash on Athlon XP CPUs
warmbloodedcreature@gmail.com reported that an APIC-enabled
Asus a7v8x-x with an Athlon XP reboots early in the bootup:

   http://bugzilla.kernel.org/show_bug.cgi?id=8723

after a long marathon of spontaneous-reboot debugging, it turns
out to be caused by sync_Arb_ids(). AMD CPUs never really needed
this sequence anyway, so just return early if we meet an AMD CPU.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-26 20:42:20 +01:00
Theodore Ts'o 8232fd6252 x86: export the symbol empty_zero_page on the 32-bit x86 architecture
The latest KVM driver wants to use the empty_zero_page symbol, and it's
not exported in 32-bit x86 (although it is exported by x86_64, s390, and
uml architectures).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: tglx@linutronix.de
Cc: linux-kernel@vger.kernel.com
Cc: kvm-devel@lists.sourceforge.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-26 20:42:19 +01:00
Andrew Morton 8645419cdb x86: fix kprobes_64.c inlining borkage
fix:

arch/x86/kernel/kprobes_64.c: In function 'set_current_kprobe':
arch/x86/kernel/kprobes_64.c:152: sorry, unimplemented: inlining failed in call to 'is_IF_modifier': recursive inlining
arch/x86/kernel/kprobes_64.c:166: sorry, unimplemented: called from here

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: mingo@elte.hu
Cc: akpm@linux-foundation.org
Cc: tglx@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-26 20:42:19 +01:00
Michal Schmidt c82bc5ad54 pci: use pci=bfsort for HP DL385 G2, DL585 G2
HP ProLiant systems DL385 G2 and DL585 G2 need pci=bfsort to enumerate PCI
devices in the expected order.

Matt sayeth:

  biosdevname is a userspace app I wrote to help solve this so we don't need
  to patch the kernel for future systems.  It's not integrated into any
  distributions properly yet, but is included in openSUSE 10.3 and Fedora 8
  for people who want to download and install it there.  It acts as a udev
  helper.

  For the time being, patching the kernel is necessary.  I really hope
  biosdevname eliminates that need in future distributions.

  http://linux.dell.com/biosdevname/

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Acked-by: Andy Gospodarek <andy@greyhouse.net>
Cc: mingo@elte.hu
Cc: andy@greyhouse.net
Cc: john.cagle@hp.com
Cc: Matt Domsch <Matt_Domsch@dell.com>
Cc: Greg KH <greg@kroah.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-26 20:42:19 +01:00
Andreas Herrmann 43517854da x86: correctly set UTS_MACHINE for "make ARCH=x86"
x86: correctly set UTS_MACHINE for "make ARCH=x86"

For a kernel built with "make ARCH=x86" the following system
information is displayed when running the new kernel

    $ uname -m
    x86

On some i386 systems (e.g. K7) we even have the following information

    $ uname -m
    x66

This is weird. The usual information for "uname -m" should be "x86_64"
on 64-bit and "i386" or "i686" on 32-bit.

This patch fixes the issue by setting UTS_MACHINE to "i386" for 32-bit
kernel builds and to "x86_64" for 64-bit kernel builds. I.e., "x86"
won't be used for UTS_MACHINE anymore.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andreas Herrmann <aherrman@arcor.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@redhat.com>
2007-11-26 20:42:19 +01:00
Peter Zijlstra 000f4a9e71 lockdep: annotate do_debug() trap handler
Ensure the hardirq state is consistent before using locks. Use the rare
trace_hardirqs_fixup() because the trap can happen in any context.

resolves this rare lockdep warning:

WARNING: at kernel/lockdep.c:2658 check_flags()
 [<c013571e>] check_flags+0x90/0x140
 [<c0138a69>] lock_release+0x4b/0x1d0
 [<c0507fea>] notifier_call_chain+0x2a/0x47
 [<c050806b>] __atomic_notifier_call_chain+0x64/0x6d
 [<c0508007>] __atomic_notifier_call_chain+0x0/0x6d
 [<c050808b>] atomic_notifier_call_chain+0x17/0x1a
 [<c0131802>] notify_die+0x30/0x34
 [<c0506b09>] do_debug+0x3e/0xd4
 [<c050658f>] debug_stack_correct+0x27/0x2c
 [<c04be389>] tcp_rcv_established+0x1/0x620
 [<c04c38c2>] tcp_v4_do_rcv+0x2b/0x313
 [<c04c56b6>] tcp_v4_rcv+0x467/0x85d
 [<c0505ff2>] _spin_lock_nested+0x27/0x32
 [<c04c5a4d>] tcp_v4_rcv+0x7fe/0x85d
 [<c04c560e>] tcp_v4_rcv+0x3bf/0x85d
 [<c04adbb5>] ip_local_deliver_finish+0x11b/0x1b0
 [<c04adac8>] ip_local_deliver_finish+0x2e/0x1b0
 [<c04ada7b>] ip_rcv_finish+0x27b/0x29a
 [<c04961e5>] netif_receive_skb+0xfb/0x2a6
 [<c04add0f>] ip_rcv+0x0/0x1fb
 [<c0496354>] netif_receive_skb+0x26a/0x2a6
 [<c04961e5>] netif_receive_skb+0xfb/0x2a6
 [<c049872e>] process_backlog+0x7f/0xc6
 [<c04983ba>] net_rx_action+0xb9/0x1ac
 [<c0498348>] net_rx_action+0x47/0x1ac
 [<c01376cb>] trace_hardirqs_on+0x118/0x16b
 [<c01225e2>] __do_softirq+0x49/0xa2
 [<c010595f>] do_softirq+0x60/0xdd
 [<c0506300>] _spin_unlock_irq+0x20/0x2c
 [<c0103e4f>] restore_nocheck+0x12/0x15
 [<c01440e1>] handle_fasteoi_irq+0x0/0x9b
 [<c0105a70>] do_IRQ+0x94/0xaa
 [<c0506300>] _spin_unlock_irq+0x20/0x2c
 [<c0104832>] common_interrupt+0x2e/0x34
 [<c0114703>] native_safe_halt+0x2/0x3
 [<c0102c01>] default_idle+0x44/0x65
 [<c010257f>] cpu_idle+0x42/0x50
 [<c076ea09>] start_kernel+0x26b/0x270
 [<c076e317>] unknown_bootoption+0x0/0x196
 =======================
irq event stamp: 559190
hardirqs last  enabled at (559190): [<c0507316>] kprobe_exceptions_notify+0x299/0x305
hardirqs last disabled at (559189): [<c05067bf>] do_int3+0x1d/0x95
softirqs last  enabled at (559172): [<c010595f>] do_softirq+0x60/0xdd
softirqs last disabled at (559181): [<c010595f>] do_softirq+0x60/0xdd

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-26 20:42:19 +01:00
Ingo Molnar bc84cf17b5 x86: turn off iommu merge by default
revert this commit for now:

    commit 9480626830
    Author: Andi Kleen <ak@suse.de>
    Date:   Fri Oct 19 20:35:03 2007 +0200

        x86: enable iommu_merge by default

it's causing regressions:

    http://bugzilla.kernel.org/show_bug.cgi?id=9412

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-26 20:42:19 +01:00
Arjan van de Ven 57c351de71 x86: printk kernel version in WARN_ON and other dump_stack users
today, all oopses contain a version number of the kernel, which is nice
because the people who actually do bother to read the oops get this
vital bit of information always without having to ask the reporter in
another round trip.

However, WARN_ON() and many other dump_stack() users right now lack this
information; the patch below adds this. This information is essential
for getting people to use their time effectively when looking at these
things; in addition, it's essential for tools that try to collect
statistics about defects.

Please consider, since its so simple and important for long term kernel
quality processes.

The code is identical between 32/64 bit; a lot of this code should be
unified over time, the patch keeps the identical-ness intact.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-26 20:42:19 +01:00
Maciej W. Rozycki d4d25deca4 x86: fix NMI watchdog & 'stopped time' problem
More than 3 years ago Niclas Gustafsson reported a 'stopped time'
problem:

> Watching the /proc/interrupts with 10s apart after the "stop".
>
> [root@s151 root]# more /proc/interrupts
>            CPU0
>   0:   66413955  local-APIC-edge  timer
[...]
> LOC:   67355837
> ERR:          0
> MIS:          0
> [root@s151 root]# more /proc/interrupts
>            CPU0
>   0:   66413955  local-APIC-edge  timer
[...]
> LOC:   67379568
> ERR:          0
> MIS:          0

This may be because buggy SMM firmware messes with the 8259A (configured
for a transparent mode -- yes that rare "local-APIC-edge" mode is tricky
;-) ) insanely.

this should resolve:

  http://bugzilla.kernel.org/show_bug.cgi?id=2544
  http://bugzilla.kernel.org/show_bug.cgi?id=6296

Patch-dusted-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-26 20:42:19 +01:00