Re: [PATCH v7 2/8] x86/crash: Introduce new options to support cpu and memory hotplug

From: Borislav Petkov
Date: Wed Apr 27 2022 - 06:58:13 EST

On Tue, Apr 26, 2022 at 03:08:26PM -0500, Eric DeVolder wrote:
> Why is it safe to examine kexec_crash_image outside the mutex? As I
> understand it, there is still the (very rare) opportunity for a kdump
> load/unload initiated via userland and this check to collide. (Similarly, I
> believe the mutex entry is almost always assured/likely.)

Yeah, I guess. As the comment in do_kexec_load() says

"KISS: always take the mutex."

so ignore this part of the diff and let's always grab the mutex.

Sorry for the confusion.