On Fri, 8 Jun 2007 22:43:25 +0200 Ingo Molnar (IM) wrote:

IM> 
IM> * Bj?rn Steinbrink <B.Steinbrink@gmx.de> wrote:
IM> 
IM> > Anyway, both are bugs and should be fixed. Maybe we're even lucky and 
IM> > it fixes your hang. *fingers crossed*
IM> 
IM> just to make it clear: the NMI watchdog was working perfectly fine on 
IM> that box (in v2.6.21 and in dozens of kernel releases before that, for 
IM> multiple years) before Andi's cleanup patch. So lets find that bug first 
IM> or revert the cleanups.
IM> 
IM> 	Ingo

None of the patches posted by Björn fix the kernel BUG at
arch/i386/kernel/cpu/perfctr-watchdog.c:126! that occurs when doing
echo 0 > /proc/sys/kernel/nmi_watchdog

Call Trace:
 [<c010c429>] single_msr_unreserve+0xd/0x1a
 [<c010c668>] disable_lapic_nmi_watchdog+0x27/0x35
 [<c0110ac6>] proc_nmi_enabled+0xa0/0xbd
 [<c018550c>] proc_sys_write+0x6f/0x8c
 [<c018549d>] proc_sys_write+0x0/0x8c
 [<c0156e5b>] vfs_write+0x8a/0x10c
 [<c0157317>] sys_write+0x41/0x67
 [<c0103c30>] syscall_call+0x7/0xb

Andi, did you have a patch for that?

Cheers,

	- Udo