Re: [coLinux-users] How to debug: "INIT: PANIC: segmentation violation at 0xb776c417! sleeping for 30 seconds."

[Henry N. <hen...@ar...>]

On 31.01.2011 05:59, Arturo R. wrote:
> On Sun, Jan 30, 2011 at 1:14 PM, Henry Nestler wrote:
>> nice, you have found a bug inside libc or with SSE2. Google for this text
>> "segfault in multiarch string function (__strlen_sse2)" and you will find
>> many of these bugs. Mostly not solved or not reproduce later.
> This one on Ubuntu's Launchpad looked specially attractive, since it
> includes a test case. Alas, I don't know how to compile/use the test
> case. There is a foo.cc file, but when I try to compile it, it
> complains about missing foo.h, which isn't in the tar archive.
>
> https://bugs.launchpad.net/ubuntu/+source/eglibc/+bug/544109

This test is for testing "cpp", that produced the bug while cpmpiling 
this code snip. This is not a source to create a test.

>> Maybe we have a problem with FPU save/restore code for SSE2 instructions
>> inside coLinux?
>> Here you need to find a testcase, that produce code like "pxor %xmm0,
>> %xmm0". Run this under coLinux to check it.
> Can you point me in the right direction of how to do this? A simple .c
> program that runs strlen on a string doesn't seem to be calling the
> assembly optimized code, and if it is, it's not causing a crash.

No, sorry I don't have such, and I also not found any usable code.

>> Boot coLinux with kernel option "nofxsr". This should disable all MMX and
>> SSE/SSE2 instructions.
> I tried it, but coLinux just crashes (coLinux .log and .conf
> attached).

I have tested "nofxsr" on my machine and it has no effect. It's normal 
working. No crashing. Maybe an other use with same Intel U7300 can check 
the usage of "nofxsr" udner coLinux.

> Should I try with a development snapshot?

This would do no matter here.

> Do you think it makes sense to file a bug report for the Debian
> package at this point?

Only, if you can reproduce this under native Linux, for example with 
debian boot cdrom and the kernel parameter "nofxsr".

-- 
Henry N.