From: Andrew Morton <akpm@linux-foundation.org>
To: Bradley Morgan <include@grrlz.net>
Cc: pmladek@suse.com, feng.tang@linux.alibaba.com,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] panic: stop CPUs that lose the panic_redirect_cpu race
Date: Tue, 7 Jul 2026 13:00:18 -0700 [thread overview]
Message-ID: <20260707130018.1281053fee6e981dcbcc0525@linux-foundation.org> (raw)
In-Reply-To: <20260707183253.9793-1-include@grrlz.net>
On Tue, 7 Jul 2026 18:32:53 +0000 Bradley Morgan <include@grrlz.net> wrote:
> Loser of the redirect cmpxchg must stop, not fall through to
> panic_try_start().
>
> This issue was found by sashiko [1].
>
Thanks, I'll queue for test-n-review.
>
> Changes since v1: a nested panic on the CPU that already holds
> panic_redirect_cpu would fail its own cmpxchg and, with v1's
> unconditional return true, halt itself and abandon the panic.
> Check old_cpu == this_cpu so the winner of a nested reentry
> falls through to panic_try_start() instead.
Sashiko ain't done yet:
https://sashiko.dev/#/patchset/20260707183253.9793-1-include@grrlz.net
next prev parent reply other threads:[~2026-07-07 20:00 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-07 18:32 [PATCH v2] panic: stop CPUs that lose the panic_redirect_cpu race Bradley Morgan
2026-07-07 20:00 ` Andrew Morton [this message]
2026-07-07 20:01 ` Bradley Morgan
2026-07-08 9:52 ` Petr Mladek
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