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

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

Hello Arturo,

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.

http://en.wikipedia.org/wiki/SSE2
Please check, that your CPU supports SSE2. You can do it under native 
Linux, or with knoppix by checking the flags from "/proc/cpuinfo". I 
think your Intel has this.

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.

Boot coLinux with kernel option "nofxsr". This should disable all MMX 
and SSE/SSE2 instructions.

Henry

On 30.01.2011 08:16, Arturo R. wrote:
> New development. After I changed the way the kernel names the
> coredumps, I realized that bash was also crashing on the exact same
> function (__strlen_sse2 () at
> ../sysdeps/i386/i686/multiarch/strlen.S:75).
>
> Armed with this information, I decided to remove the libc6-i686
> package and now the system no longer crashes when resuming from
> standby.
>
> I would still love to help out in figuring out a proper fix, if you
> Henry, or anyone else, would like to work with me.
>
> Thanks again.
>
> gdb-bash.log
>
>
> root@colinux:~/src# gdb --quiet /bin/bash coredump.bash.1296369722
> Reading symbols from /bin/bash...done.
> [New Thread 1592]
>
> warning: Can't read pathname for load map: Input/output error.
> Reading symbols from /lib/libncurses.so.5...(no debugging symbols found)...done.
> Loaded symbols for /lib/libncurses.so.5
> Reading symbols from /lib/i686/cmov/libdl.so.2...done.
> Loaded symbols for /lib/i686/cmov/libdl.so.2
> Reading symbols from /lib/i686/cmov/libc.so.6...done.
> Loaded symbols for /lib/i686/cmov/libc.so.6
> Reading symbols from /lib/ld-linux.so.2...done.
> Loaded symbols for /lib/ld-linux.so.2
> Reading symbols from /lib/i686/cmov/libnss_compat.so.2...done.
> Loaded symbols for /lib/i686/cmov/libnss_compat.so.2
> Reading symbols from /lib/i686/cmov/libnsl.so.1...done.
> Loaded symbols for /lib/i686/cmov/libnsl.so.1
> Reading symbols from /lib/i686/cmov/libnss_nis.so.2...done.
> Loaded symbols for /lib/i686/cmov/libnss_nis.so.2
> Reading symbols from /lib/i686/cmov/libnss_files.so.2...done.
> Loaded symbols for /lib/i686/cmov/libnss_files.so.2
> Core was generated by `-bash'.
> Program terminated with signal 11, Segmentation fault.
> #0  __strlen_sse2 () at ../sysdeps/i386/i686/multiarch/strlen.S:75
> 75              pxor    %xmm0, %xmm0            /* 16 null chars */