Re: [BUG RT] dump-capture kernel not executed for panic in interrupt context

From: Joerg Vehlow
Date: Mon Sep 07 2020 - 13:50:09 EST




On 9/7/2020 1:46 PM, peterz@xxxxxxxxxxxxx wrote:
I think it's too complicated for that is needed, did you see my
suggestion from a year ago? Did i miss something obvious?

This one? https://lore.kernel.org/linux-fsdevel/20191219090535.GV2844@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/

I think it may be a bit incorrect?
According to the original comment in __crash_kexec, the mutex was used to
prevent a sys_kexec_load, while crash_kexec is executed. Your proposed patch
does not lock the mutex in crash_kexec. This does not cover the original use
case anymore. The only thing that is protected now are two panicing cores at
the same time.
Actually, this implementation feels even more hacky to me....

Jörg