2005-11-10 14:35:31

by Lee

[permalink] [raw]
Subject: 4k stack overflow and stack traces

Hello,

When I am running with 4k stacks enabled, my kernel completely locks up when I get a high load.

When I am running with 4k stacks disabled, my kernel runs stabely.

From the few kernel output I can get on the serial port, I see some type of recursive kernel fault.

Is there a way to get a stacktrace in this case so we can identify which execution path is causing this stack overflos ?

Attached is the output form the serial port which shows some type of recursive kernel fault.

Thanks,
Lee



--
Lee
[email protected]

08:31:20 up 3 days, 13:41, 0 users, load average: 0.47, 0.34, 0.19


Attachments:
(No filename) (607.00 B)
kernel-2.6.13-gentoo-r3-crash.txt (5.27 kB)
Download all attachments

2005-11-15 20:31:03

by Benjamin LaHaise

[permalink] [raw]
Subject: Re: 4k stack overflow and stack traces

On Thu, Nov 10, 2005 at 08:35:25AM -0600, Lee wrote:
> Is there a way to get a stacktrace in this case so we can identify which
> execution path is causing this stack overflos ?

It could be done... Before coming up with a patch for that, what sort of
setup are you running -- filesystem, raid array, drivers, etc? Combined
with the results of a 'make checkstack' that's usually enough to get an
idea where the problem is. Thanks,

-ben

2005-11-15 22:40:13

by Lee

[permalink] [raw]
Subject: Re: 4k stack overflow and stack traces

> It could be done... Before coming up with a patch for that, what sort of
> setup are you running -- filesystem, raid array, drivers, etc? Combined
> with the results of a 'make checkstack' that's usually enough to get an
> idea where the problem is. Thanks,

see attached for filesystems, devices, current kernel build config

do you advise doing a make checkstack before or after the patch that you speak of making?

I also have iptables configured with nat for local connections enabled

i am also using ethernet bridge (intended for apps like pearpc and qemu, which i use very infrequently).



--
Lee
[email protected]

16:30:41 up 8 days, 21:41, 0 users, load average: 0.04, 0.05, 0.01


Attachments:
(No filename) (710.00 B)
bzImage-config (26.88 kB)
lspci.txt (1.30 kB)
filesystems.txt (406.00 B)
Download all attachments

2005-11-16 17:36:26

by Benjamin LaHaise

[permalink] [raw]
Subject: Re: 4k stack overflow and stack traces

On Tue, Nov 15, 2005 at 04:40:05PM -0600, Lee wrote:
> see attached for filesystems, devices, current kernel build config
>
> do you advise doing a make checkstack before or after the patch that you speak of making?

Yes please, that will give us all the datapoints from your particular
gcc version, config and modules.

> I also have iptables configured with nat for local connections enabled
>
> i am also using ethernet bridge (intended for apps like pearpc and qemu,
> which i use very infrequently).

Hmmm, does it trigger on any particular network traffic? I'm wondering
if one of the masquerading modules you're using happens to eat just
enough stack when mixed with the bridging configuration.

-ben