Commit Graph

20 Commits

Author SHA1 Message Date
Aristeu Rozanski
b3e15bdef6 x86, NMI watchdog: setup before enabling NMI watchdog
There's a small window when NMI watchdog is being set up that if any NMIs
are triggered, the NMI code will make make use of not initalized wd_ops
elements:
	void setup_apic_nmi_watchdog(void *unused)
	{
		if (__get_cpu_var(wd_enabled))
			return;

		/* cheap hack to support suspend/resume */
		/* if cpu0 is not active neither should the other cpus */
		if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0)
			return;

		switch (nmi_watchdog) {
		case NMI_LOCAL_APIC:
			/* enable it before to avoid race with handler */
-->			__get_cpu_var(wd_enabled) = 1;
-->			if (lapic_watchdog_init(nmi_hz) < 0) {
(...)
	asmlinkage notrace __kprobes void default_do_nmi(struct pt_regs *regs)
	{
	(...)
			if (nmi_watchdog_tick(regs, reason))
				return;
(...)
	notrace __kprobes int
	nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
	{
	(...)
		if (!__get_cpu_var(wd_enabled))
			return rc;
		switch (nmi_watchdog) {
		case NMI_LOCAL_APIC:
			rc |= lapic_wd_event(nmi_hz);
(...)
int lapic_wd_event(unsigned nmi_hz)
{
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
	u64 ctr;

-->	rdmsrl(wd->perfctr_msr, ctr);

and wd->*_msr will be initialized on each processor type specific setup, after
enabling NMIs for PMIs. Since the counter was just set, the chances of an
performance counter generated NMI is minimal, but any other unknown NMI would
trigger the problem. This patch fixes the problem by setting everything up
before enabling performance counter generated NMIs and will set wd_enabled
using a callback function.

Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-22 19:48:19 +02:00
Ingo Molnar
8bb851900f x86, nmi: clean UP NMI watchdog failure message
clean up the failure message - and redirect people to bugzilla
instead of lkml.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 15:35:31 +02:00
Aristeu Rozanski
1563666844 x86, NMI: fix watchdog failure message
> it just won't work at boot time - the second logic unit will be stuck:
>
> Booting processor 1/2 APIC 0x1
> Initializing CPU#1
> Calibrating delay using timer specific routine.. 5586.12 BogoMIPS (lpj=2793063)
> CPU: Trace cache: 12K uops, L1 D cache: 16K
> CPU: L2 cache: 1024K
> CPU: Physical Processor ID: 0
> CPU: Processor Core ID: 1
> CPU1: Thermal monitoring enabled (TM1)
>               Intel(R) Pentium(R) D CPU 2.80GHz stepping 04
> Brought up 2 CPUs
> testing NMI watchdog ... <4>WARNING: CPU#1: NMI appears to be stuck (0->0)!

while at it... - fix that newline

Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Cc: jvillalo@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 15:34:59 +02:00
Ingo Molnar
acee709cab Merge branches 'x86/urgent', 'x86/amd-iommu', 'x86/apic', 'x86/cleanups', 'x86/core', 'x86/cpu', 'x86/fixmap', 'x86/gart', 'x86/kprobes', 'x86/memtest', 'x86/modules', 'x86/nmi', 'x86/pat', 'x86/reboot', 'x86/setup', 'x86/step', 'x86/unify-pci', 'x86/uv', 'x86/xen' and 'xen-64bit' into x86/for-linus 2008-07-21 16:37:17 +02:00
Simon Arlott
e3a61b0a8c x86: add unknown_nmi_panic kernel parameter
It's not possible to enable the unknown_nmi_panic sysctl option
until init is run. It's useful to be able to panic the kernel
during boot too, this adds a parameter to enable this option.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 10:10:31 +02:00
Maciej W. Rozycki
593f4a788e x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time.  Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum.  Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends.  The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.

I had the feeling no one else was brave enough to do it, so I went ahead
and here it is.  Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.

I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out.  The option will get removed from them at
the next run.

Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 12:51:21 +02:00
Ingo Molnar
1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Maciej W. Rozycki
5b4d2386c2 x86: Recover timer_ack lost in the merge of the NMI watchdog
In the course of the recent unification of the NMI watchdog an assignment
to timer_ack to switch off unnecesary POLL commands to the 8259A in the
case of a watchdog failure has been accidentally removed.  The statement
used to be limited to the 32-bit variation as since the rewrite of the
timer code it has been relevant for the 82489DX only.  This change brings
it back.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 20:54:03 +02:00
Cyrill Gorcunov
4de0043617 x86: nmi_watchdog - introduce nmi_watchdog_active() helper
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 12:51:42 +02:00
Cyrill Gorcunov
c376d45432 x86: nmi_watchdog - use NMI_NONE by default
There is no need to keep NMI_DISABLED definition and use it
for nmi_watchdog by default. Here is the point why:

- IO-APIC and APIC chips are programmed for nmi_watchdog support at very
  early stage of kernel booting and not having nmi_watchdog specified as
  boot option lead only to nmi_watchdog becomes to NMI_NONE anyway
- enable nmi_watchdog thru /proc/sys/kernel/nmi if it was not specified at
  boot is not possible too (even having this sysfs entry)

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 12:51:41 +02:00
Cyrill Gorcunov
2b6addad2d x86: nmi_watchdog - remove useless check
Since nmi_watchdog is unsigned variable we may
safely remove the check for negative value.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 12:51:40 +02:00
Ingo Molnar
4b62ac9a2b Merge branch 'x86/nmi' into x86/devel
Conflicts:

	arch/x86/kernel/nmi.c
	arch/x86/kernel/nmi_32.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 12:17:08 +02:00
Glauber Costa
b8e0418b2a x86: fix typo CONFIX -> CONFIG
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 11:59:11 +02:00
Cyrill Gorcunov
f781b03c4b x86: touch_nmi_watchdog(): reset alert counters for supported nmi_watchdog modes only
The checking 'if nmi_watchdog > 0' (ie NMI_NONE) is quite fast but it
has a side effect - it's taken even if nmi_watchdog = NMI_DISABLED.

Nowadays nmi_watchdog is set up to NMI_NONE by default so this condition
is properly taken most the time but we better show this explicitly.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-12 15:14:54 +02:00
mingo@elte.hu
75b9f5d2a0 x86, nmi: fix build
fix:

arch/x86/kernel/built-in.o: In function `proc_nmi_enabled':
: undefined reference to `nmi_watchdog_default'
arch/x86/kernel/built-in.o: In function `native_smp_prepare_cpus':
: undefined reference to `nmi_watchdog_default'

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-05 15:15:10 +02:00
Cyrill Gorcunov
3ed3f06295 x86: nmi - consolidate nmi_watchdog_default for 32bit mode
64bit mode bootstrap code does set nmi_watchdog to NMI_NONE
by default and doing the same on 32bit mode is safe too.
Such an action saves us from several #ifdef.

Btw, my previous commit

commit 19ec673ced
Author: Cyrill Gorcunov <gorcunov@gmail.com>
Date:   Wed May 28 23:00:47 2008 +0400

    x86: nmi - fix incorrect NMI watchdog used by default

did not fix the problem completely, moreover it
introduced additional bug - nmi_watchdog would be
set to either NMI_LOCAL_APIC or NMI_IO_APIC
_regardless_ to boot option if being enabled thru
/proc/sys/kernel/nmi_watchdog. Sorry for that.
Fix it too.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: macro@linux-mips.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-06-05 15:13:59 +02:00
Ingo Molnar
3d1ba1da2b x86: fix nmi.c build bug
apic.h needs to be included for the apic_write_around() definition.
2008-06-02 13:57:12 +02:00
Hiroshi Shimamoto
88ff0a474e x86: coding style fixes for nmi.c
before
	total: 1 errors, 6 warnings, 534 lines checked
after
	total: 0 errors, 1 warnings, 532 lines checked

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 12:53:54 +02:00
Cyrill Gorcunov
19ec673ced x86: nmi - fix incorrect NMI watchdog used by default
The commit

	commit 4b82b27770
	Author: Cyrill Gorcunov <gorcunov@gmail.com>
	Date:   Sat May 24 19:36:35 2008 +0400

set nmi_watchdog to NMI_IO_APIC as by default. This causes hangs on some
machines with buggy watchdogs. Fix it - i.e. restore old behaviour.

Thanks to Sitsofe Wheeler and Adrian Bunk for catching the problem
and Maciej W. Rozycki for explanation what is going on there.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
CC: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-28 21:04:53 +02:00
Cyrill Gorcunov
1798bc22b2 x86: nmi_32/64.c - merge down nmi_32.c and nmi_64.c to nmi.c
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: hpa@zytor.com
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 22:32:51 +02:00