linux/arch
Vegard Nossum 4461145ef1 x86, lockdep: fix "WARNING: at kernel/lockdep.c:2658 check_flags+0x4c/0x128()"
Alessandro Suardi reported:
> Recently upgraded my FC6 desktop to Fedora 9; with the
>  latest nautilus RPM updates my VNC session went nuts
>  with nautilus pegging the CPU for everything that breathed.
>
> I now reverted to an earlier nautilus package, but during
>  the peak CPU period my kernel spat this:
>
> [314185.623294] ------------[ cut here ]------------
> [314185.623414] WARNING: at kernel/lockdep.c:2658 check_flags+0x4c/0x128()
> [314185.623514] Modules linked in: iptable_filter ip_tables x_tables
> sunrpc ipv6 fuse snd_via82xx snd_ac97_codec ac97_bus snd_mpu401_uart
> snd_rawmidi via686a hwmon parport_pc sg parport uhci_hcd ehci_hcd
> [314185.623924] Pid: 12314, comm: nautilus Not tainted 2.6.26-rc5-git2 #4
> [314185.624021]  [<c0115b95>] warn_on_slowpath+0x41/0x7b
> [314185.624021]  [<c010de70>] ? do_page_fault+0x2c1/0x5fd
> [314185.624021]  [<c0128396>] ? up_read+0x16/0x28
> [314185.624021]  [<c010de70>] ? do_page_fault+0x2c1/0x5fd
> [314185.624021]  [<c012fa33>] ? __lock_acquire+0xbb4/0xbc3
> [314185.624021]  [<c012d0a0>] check_flags+0x4c/0x128
> [314185.624021]  [<c012fa73>] lock_acquire+0x31/0x7d
> [314185.624021]  [<c0128cf6>] __atomic_notifier_call_chain+0x30/0x80
> [314185.624021]  [<c0128cc6>] ? __atomic_notifier_call_chain+0x0/0x80
> [314185.624021]  [<c0128d52>] atomic_notifier_call_chain+0xc/0xe
> [314185.624021]  [<c0128d81>] notify_die+0x2d/0x2f
> [314185.624021]  [<c01043b0>] do_int3+0x1f/0x4d
> [314185.624021]  [<c02f2d3b>] int3+0x27/0x2c
> [314185.624021]  =======================
> [314185.624021] ---[ end trace 1923f65a2d7bb246 ]---
> [314185.624021] possible reason: unannotated irqs-off.
> [314185.624021] irq event stamp: 488879
> [314185.624021] hardirqs last  enabled at (488879): [<c0102d67>]
> restore_nocheck+0x12/0x15
> [314185.624021] hardirqs last disabled at (488878): [<c0102dca>]
> work_resched+0x19/0x30
> [314185.624021] softirqs last  enabled at (488876): [<c011a1ba>]
> __do_softirq+0xa6/0xac
> [314185.624021] softirqs last disabled at (488865): [<c010476e>]
> do_softirq+0x57/0xa6
>
> I didn't seem to find it with some googling, so here it is.
>
> I was incidentally ltracing that process to try and find out
>  what was gulping down that much CPU (sorry, no idea
>  whether ltrace and the WARNING happened at the same
>  time or which came first) and:

Yeah, this is extremely likely to be the source of the warning.

The warning should be harmless, however.

> Box is my trusty noname K7-800, 512MB RAM; if there's
>  anything else useful I might be able to provide, just ask.

It would be interesting to see where the int3 comes from.  Too bad,
lockdep doesn't provide the register dump. The stacktrace also doesn't
go further than the int3(), I wonder if this int3 came from userspace?
The ltrace readme says "software breakpoints, like gdb", so I guess
this is the case. Yep, seems like it.

This looks relevant:

| commit fb1dac909d
| Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
| Date:   Wed Jan 16 09:51:59 2008 +0100
|
|     lockdep: more hardirq annotations for notify_die()

I'm attaching a similarly-looking patch for this case (DO_VM86_ERROR),
though I suspect it might be missing for the other cases
(DO_ERROR/DO_ERROR_INFO) as well.

Reported-by: Alessandro Suardi <alessandro.suardi@gmail.com>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-12 21:27:19 +02:00
..
alpha [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
arm [ARM] pxa: fix tosa.c build error 2008-06-02 20:38:15 +01:00
avr32 avr32: Fix cpufreq oops when ondemand governor is default 2008-05-27 09:37:42 +02:00
blackfin Blackfin arch: protect only the SPI bus controller with CONFIG_SPI_BFIN 2008-06-07 15:03:01 +08:00
cris [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
frv Fix various old email addresses for dwmw2 2008-06-06 11:29:10 -07:00
h8300 [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
ia64 [IA64] Workaround for RSE issue 2008-05-27 13:24:39 -07:00
m32r [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
m68k m68k: enable CONFIG_COMPAT_BRK by default 2008-06-06 11:29:09 -07:00
m68knommu [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
mips Fix divide by zero error in build_clear_page() and build_copy_page() 2008-06-05 18:13:16 +01:00
mn10300 [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
parisc [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
powerpc [POWERPC] Make walk_memory_resource available with MEMORY_HOTPLUG=n 2008-06-09 11:32:41 +10:00
ppc [POWERPC] Export empty_zero_page and copy_page in arch/ppc 2008-05-31 17:08:28 +10:00
s390 [S390] Update default configuration. 2008-05-30 10:03:36 +02:00
sh sh: Add -mno-fdpic to default flags. 2008-06-09 16:49:43 +09:00
sparc sparc: switch /proc/led to seq_file 2008-06-03 15:21:21 -07:00
sparc64 sparc64: Prevent stack backtrace false positives on trap frames. 2008-05-21 21:50:01 -07:00
um uml: PATH_MAX needs limits.h 2008-06-06 11:29:10 -07:00
v850 [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
x86 x86, lockdep: fix "WARNING: at kernel/lockdep.c:2658 check_flags+0x4c/0x128()" 2008-06-12 21:27:19 +02:00
xtensa [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
.gitignore
Kconfig dma: add dma_*map*_attrs() interfaces 2008-04-29 08:06:11 -07:00