Linux server crash (kernel NULL pointer dereference + soft lockup - CPU#1 stuck)
 

I have a Linux 3.2.0-4-amd64 #1 SMP Debian 3.2.46-1 x86_64 GNU/Linux server that keeps crashing, usually once every 24-72 hours.

I run lighttpd, mysql, haproxy and a couple of always-running java processes together with a bunch of shorter-lived java processes.

Below I have linked the /var/log/syslog and /var/log/messages. They both contain the kernel NULL pointer dereference and the soft lockup bugs lines.

syslog: http://pastebin.com/7VxdkEYu
messages: http://pastebin.com/UdiN2y0d
dmesg: http://pastebin.com/8iQC5c0K

Do anyone have any idea on how to debug this?

Thanks

I can't see any obvious errors, on the next crash, try strace
It's also worth considering hardware failure.

How can i use strace when the system have crashed?

I'm renting the server and they did a full hardware test and found no errors, besides I'm getting this on multiple servers.

Crashed again now while i got a terminal open, got this just before it died: