Re: KVM induced panic on 2.6.38[2367] & 2.6.39

From: Brad Campbell
Date: Tue May 31 2011 - 10:24:54 EST


On 31/05/11 18:38, Borislav Petkov wrote:
On Tue, May 31, 2011 at 05:26:10PM +0800, Brad Campbell wrote:
On 31/05/11 13:47, Borislav Petkov wrote:
Looks like a KSM issue. Disabling CONFIG_KSM should at least stop your
machine from oopsing.

Adding linux-mm.


I initially thought that, so the second panic was produced with KSM
disabled from boot.

echo 0> /sys/kernel/mm/ksm/run

If you still think that compiling ksm out of the kernel will prevent
it then I'm willing to give it a go.

Ok, from looking at the code, when KSM inits, it starts the ksm kernel
thread and it looks like your oops comes from the function that is run
in the kernel thread - ksm_scan_thread.

So even if you disable it from sysfs, it runs at least once.


Just to confirm, I recompiled 2.6.38.7 without KSM enabled and I've been unable to reproduce the bug, so it looks like you were on the money.

I've moved back to 2.6.38.7 as 2.6.39 has a painful SCSI bug that panics about 75% of boots, and the reboot cycle required to get luck my way into a working kernel is just too much hassle.

It would appear that XP zero's its memory space on bootup, so there would be lots of pages to merge with a couple of relatively freshly booted XP machines running.

Regards,
Brad.
--
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/