After upgrading Apache and PHP, a specific function causes a segmentation error

Question

I manually migrate this question from drupal.stackexchange.com (it has since been deleted).

I recently updated my local dev environment (Vagrant, Ubuntu 12.04) from PHP 5.3.X to 5.5.14 and Apache 2.2.X to 2.4.9. After the update, whenever I call the dpm() debugging function , it causes a segmentation error. Excerpt from Apache Logs:

[Wed Jul 09 14: 33: 11.474063 2014] [core: notice] [pid 6513] AH00051: child pid 6644 output signal segmentation error (11), possible coredump in / etc / apache 2
[Wed Jul 09 14: 33: 18.483516 2014] [core: notice] [pid 6513] AH00051: child pid 6640 output signal segmentation error (11), possible coredump in / etc / apache 2
[Wed Jul 09 14: 33: 25.494786 2014] [kernel: notification] [pid 6513] AH00051: child pid 6619 output signal Segmentation error (11), possible coredump in / etc / apache 2

Please note that after updating PHP and Apache, I later decided to upgrade Ubuntu to 14.04. The problem remains the same.

Drupal 7.30
Devel 7.x-1.5 (Drupal module)

Disabling OpCache did not solve the problem.

I installed gdb and got a kernel dump. Here are the results:

 /vagrant/web [git::goomba *] [ vagrant@dev ] [9:04] > gdb apache2 -core core GNU gdb (Ubuntu 7.7-0ubuntu3.1) 7.7 Copyright (C) 2014 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-linux-gnu". Type "show configuration" for configuration details. For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>. Find the GDB manual and other documentation resources online at: <http://www.gnu.org/software/gdb/documentation/>. For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from apache2...(no debugging symbols found)...done. [New LWP 8265] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Core was generated by `/usr/sbin/apache2 -k start'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007fd091fda437 in ?? () from /usr/lib/apache2/modules/libphp5.so 

And when I run (gdb) backtrace full :

 #0 0x00007fd091fda437 in ?? () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #1 0x00007fd091fdb044 in vspprintf () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #2 0x00007fd092038537 in zend_error_noreturn () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #3 0x00007fd09205d7ff in zend_std_read_property () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #4 0x00007fd0920633c7 in ?? () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #5 0x00007fd0920a7178 in execute_ex () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #6 0x00007fd092027e86 in dtrace_execute_ex () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #7 0x00007fd0920e2f27 in ?? () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #8 0x00007fd0920a7178 in execute_ex () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #9 0x00007fd092027e86 in dtrace_execute_ex () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #10 0x00007fd0920e2f27 in ?? () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #11 0x00007fd0920a7178 in execute_ex () from /usr/lib/apache2/modules/libphp5.so No symbol table info available. #12 0x00007fd092027e86 in dtrace_execute_ex () 

dpm() Details

This is a debugging function that fairly prints a PHP variable. Under the hood, it uses Krumo , in particular, it calls krumo::dump() .

Answer 1

I stopped this problem for a while and therefore stopped using the dpm() function, which caused problems. At some point, this problem went away for me. I am not sure I fixed this. My guess is PHP / Apache / Drupal updates, but I can’t say for sure.

Answer 2

I had a very similar problem here Error (many):

[core: notification] [pid 1550] AH00051: exit signal for a child pid 2226 Segmentation error (11), possible error in the / etc / apache 2 file

the culprit was xcache deleted:

 apt-get --purge remove php5-xcache 

Using Apache 2.4.7

php -v output:

PHP 5.5.9-1ubuntu4.5 (cli) (built: Oct 29, 2014 11:59:10)