Hi, Cong Wang Thank you for taking the time to respond to me. Do you think the message(i.e. "RCU detect a stall on CPU 2") indicates there is a lockup. Cong Wang <xiyou.wangcong@gmail.com> 于2020年7月1日周三 下午2:07写道：
On Tue, Jun 30, 2020 at 7:49 PM 孙世龙 sunshilong <sunshilong369@gmail.com> wrote:
Hi, list
My x86 machine(linux4.19) sometimes hangs, suddenly not responding in any way to the mouse or the keyboard.
How can I investigate why it hung up? Is there extra information I can find for a clue? Is there anything less drastic than power-off to get some kind of action, if only some limited shell or just beeps, but might give a clue?
If the hang was a crash which you didn't get a chance to capture the last kernel log, you can use kdump to collect them. The kernel log tells what kind of crash it is, a NULL pointer deref, a kernel page fault etc..
If the hang was a hard lockup, you have to turn on lockup detector and also kdump to capture what the detector tells.
Thanks.