Hi All, I looked into my issue and i had only one cpu on that machine and i was getting messages like process # waiting for # secs. My theory is that this process was of doing some kind of busy looping on that cpu so that the operating system could not even generate a dump. The moment i increased the number of cpus i got the dump. I am just posting this because someone else may find it useful. Regards, Neha On Thu, May 30, 2013 at 11:44 AM, <Valdis.Kletnieks@vt.edu> wrote:
On Thu, 30 May 2013 11:31:49 -0600, neha naik said:
I have loaded the linux crashdump on ubuntu machine. I can manually generate the crashdump by the 'echo c > /proc/sysrq-trigger'. However, i am having a panic in a module i have written, which is not generating a core dump. I simply see the stack in the console and it kind of hangs there. I have to manually power it off and power it on ... Can someone explain why this happens? Is it because the kernel has gone into such a state that it cannot even follow the procedure for crash dump.
Most likely, your module isn't in fact panic'ing, but oops'ing. There's a number of kernel variables that control whether to panic.
ls -l /proc/sys/kernel/*panic*
and for example 'echo 1 > /proc/sys/kernel/panic_on_oops' will cause a panic if something oops'es.