From: Dominique Martinet <asmadeus@codewreck.org>
To: Yifei Chu <yifeichu24@gmail.com>
Cc: v9fs@lists.linux.dev, Eric Van Hensbergen <ericvh@kernel.org>,
Latchesar Ionkov <lucho@ionkov.net>,
Christian Schoenebeck <linux_oss@crudebyte.com>,
linux-kernel@vger.kernel.org
Subject: Re: [BUG] 9p: unknown RLOCK status triggers WARN_ONCE panic with panic_on_warn
Date: Fri, 29 May 2026 12:11:30 +0900 [thread overview]
Message-ID: <ahkD4tMzJR3qA0Bu@codewreck.org> (raw)
In-Reply-To: <CAPJnbgJ7ZK7DCjCfG56hd_iKGePmAzudb4hOWd4=9r32nM+KcA@mail.gmail.com>
Yifei Chu wrote on Sun, May 24, 2026 at 10:43:57AM -0400:
> Short version: I found that a 9P2000.L server can return an unknown RLOCK
> status byte and make the Linux 9P client hit a WARN_ONCE() in
> v9fs_file_do_lock(). With panic_on_warn=1, that turns into a reproducible
> kernel panic.
You're right we should not WARN() due to server sending us bogus data
(only on internal state bug)
Please send a patch directly next time, especially since this is trivial
I've saved us both time for this time:
https://lore.kernel.org/r/20260529-lock-warn-v1-1-20c29580d61d@codewreck.org
--
Dominique
prev parent reply other threads:[~2026-05-29 3:11 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-24 14:43 [BUG] 9p: unknown RLOCK status triggers WARN_ONCE panic with panic_on_warn Yifei Chu
2026-05-29 3:11 ` Dominique Martinet [this message]
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