Debugging apache seg fault with gdb

Posted by Joyce Babu on Server Fault See other posts from Server Fault or by Joyce Babu
Published on 2012-10-29T10:52:53Z Indexed on 2012/10/29 11:03 UTC
Read the original article Hit count: 282

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debugging

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segfault

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gdb

Apache on a production server of mine is seg faulting intermittently. I have enabled core dump option in apache configuration and have several dumped core files. Unfortunately, since it is a production server, apache or the loaded modules are not compiled with debug symbols. From what I understand, gdb cannot do much without debug symbols.

Can I at least find out which module is causing the seg fault, without debug symbols? If so, how?

Following is the output from a gdb backtrace

(gdb) bt full
#0  0xb7f1f832 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
No symbol table info available.
#1  0xb7be82bc in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
No symbol table info available.
#2  0xb771652a in ?? () from /usr/local/apache/modules/mod_pagespeed.so
No symbol table info available.
#3  0xb75df576 in ?? () from /usr/local/apache/modules/mod_pagespeed.so
No symbol table info available.
#4  0xb7715c20 in ?? () from /usr/local/apache/modules/mod_pagespeed.so
No symbol table info available.
#5  0xb7be4a49 in start_thread () from /lib/libpthread.so.0
No symbol table info available.
#6  0xb7b2a63e in clone () from /lib/libc.so.6
No symbol table info available.

Does this mean that /lib/ld-linux.so.2 is causing the seg fault?

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