Re: 2.6.14-rc4-rt7

From: William Weston
Date: Wed Oct 26 2005 - 19:03:03 EST


On Wed, 26 Oct 2005, john stultz wrote:

> On Wed, 2005-10-26 at 15:07 -0700, William Weston wrote:
> > On Wed, 26 Oct 2005, Rui Nuno Capela wrote:
> >
> > > Just noticed a couple or more of this on dmesg. Maybe its old news and
> > > being discussed already. Otherwise my P4@xxxxxxx/UP laptop boots and
> > > runs without hicups on 2.6.14-rc5-rt7 (config.gz attached).
> > >
> > > ... time warped from 13551912584 to 13551905960.
> > > ... system time: 13488892865 .. 13488892865.
> > > udevstart/1579[CPU#0]: BUG in get_monotonic_clock_ts at
> > > kernel/time/timeofday.c:
> > > 262
> > > [<c0116fcb>] __WARN_ON+0x4f/0x6c (8)
> > > [<c012f8b0>] get_monotonic_clock_ts+0x27a/0x2f0 (40)
> > > [<c0141c9d>] kmem_cache_alloc+0x51/0xac (76)
> > > [<c0114826>] copy_process+0x2ff/0xeed (44)
> > > [<c0139444>] unlock_page+0x17/0x4a (12)
> > > [<c0147a8a>] do_wp_page+0x245/0x372 (20)
> > > [<c01154f5>] do_fork+0x69/0x1b5 (56)
> > > [<c02c120b>] do_page_fault+0x432/0x543 (32)
> > > [<c01017aa>] sys_clone+0x32/0x36 (72)
> > > [<c0102a9b>] sysenter_past_esp+0x54/0x75 (16)
> >
> > I'm getting these with two different machines running 2.6.14-rc5-rt7 with
> > Steven's ktimer_interrupt() patch from yesterday. Did not see these with
> > previous -rt kernels. Shutting down NTP makes no difference.
> >
> > This is from the athlon-xp/via-kt400 box (xeon smt box looks similar):
>
> I'm grabbing rt7 to try to reproduce this. Not yet sure what the cause
> could be. From Rui's dmesg the tsc clocksource was being used, I assume
> this is the case with you as well, William?

Yes, tsc is used:

Time: tsc clocksource has been installed.
Ktimers: Switched to high resolution mode CPU 0

Full dmesg and config is attached to my previous email. I just built a
debug -rt7 so I can grab some latency traces if need be. Should I try
disabling high res timers?


Cheers,
--ww
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/