[debian-mysql] Bug#426789: mysql-server-5.0 hangs/deadlocks on startup with user=mysql

[Roland Lammel]

Package: mysql-server-5.0
Version: 5.0.38-1
Severity: important


After an failing upgrade to mysql-server-5.0.38-1 mysql failed to start.

mysqld had to be killed with SIGKILL to be aborted.
All subsequent tries to start mysql failed.

Although processes started up, mysql hung completly, not responding to mysql
client connections through socket or tcp. No error log was written.

The cause is a thread deadlock problem when using --user=mysql commandline
option or user=mysql in /etc/mysql/my.cnf

I can't remember if I had this setting before, but after 5.0.32 mysql failed to
start for me.

There are 2 possible workarounds for debian:

* Use "user=root" in my.cnf, do not use --user=mysql
  cli option for all mysql binaries using threads
* "su - mysql" before starting mysql server
  and affected mysql binaries

As this might result in a unusable package/upgrade raising priority should be
considered.

No further information is included here as a workaround is already found in the
mysql bugtracker: http://bugs.mysql.com/bug.php?id=28690

If you need further information, let me know.

+rl

-- System Information:
Debian Release: lenny/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)

Kernel: Linux 2.6.18-3-686 (SMP w/2 CPU cores)
Locale: LANG=de_AT at euro, LC_CTYPE=de_AT at euro (charmap=ISO-8859-15)
Shell: /bin/sh linked to /bin/bash

Versions of packages mysql-server-5.0 depends on:
ii  adduser                     3.102        Add and remove users and groups
ii  debconf [debconf-2.0]       1.5.13       Debian configuration management sy
ii  libc6                       2.3.6.ds1-8  GNU C Library: Shared libraries
ii  libdbi-perl                 1.53-1       Perl5 database interface by Tim Bu
ii  libgcc1                     1:4.1.1-21   GCC support library
ii  libmysqlclient15off         5.0.38-1     mysql database client library
ii  libncurses5                 5.5-5        Shared libraries for terminal hand
ii  libreadline5                5.2-2        GNU readline and history libraries
ii  libstdc++6                  4.1.1-21     The GNU Standard C++ Library v3
ii  libwrap0                    7.6.dbs-13   Wietse Venema's TCP wrappers libra
ii  lsb-base                    3.1-23.1     Linux Standard Base 3.1 init scrip
ii  mysql-client-5.0            5.0.38-1     mysql database client binaries
ii  mysql-common                5.0.38-1     mysql database common files (e.g. 
ii  passwd                      1:4.0.18.1-7 change and administer password and
ii  perl                        5.8.8-7      Larry Wall's Practical Extraction 
ii  psmisc                      22.3-1       Utilities that use the proc filesy
ii  zlib1g                      1:1.2.3-13   compression library - runtime

Versions of packages mysql-server-5.0 recommends:
ii  mailx            1:8.1.2-0.20050715cvs-1 A simple mail user agent

-- debconf information:
  mysql-server-5.0/really_downgrade: false
  mysql-server-5.0/start_on_boot: true
  mysql-server-5.0/nis_warning:
  mysql-server-5.0/postrm_remove_databases: false
  mysql-server-5.0/no_upgrade_with_isam_tables:
* mysql-server-5.0/mysql_install_db_notes:
* mysql-server-5.0/need_sarge_compat: false
  mysql-server/error_setting_password:
  mysql-server-5.0/need_sarge_compat_done: true