linux-kernel - Re: [PATCH] locking/mutex: Disable preemption in __mutex_unlock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHk-=whVBKwK83R_7+52qzZb3DpFWGG8L=V5bDG6VS44e3=1-A@mail.gmail.com>
Date: Wed, 9 Jul 2025 11:21:57 -0700
From: Linus Torvalds <torvalds@...ux-foundation.org>
To: Waiman Long <longman@...hat.com>
Cc: Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>, 
	Will Deacon <will@...nel.org>, Boqun Feng <boqun.feng@...il.com>, Jonathan Corbet <corbet@....net>, 
	linux-kernel@...r.kernel.org, Jann Horn <jannh@...gle.com>
Subject: Re: [PATCH] locking/mutex: Disable preemption in __mutex_unlock_slowpath()

On Wed, 9 Jul 2025 at 11:19, Linus Torvalds
<torvalds@...ux-foundation.org> wrote:
>
> I absolutely detest the notion of "let's make locking be tied to
> object lifetimes".

Side note: I wonder if there's any way to detect this kind of race in general.

And I suspect it would involve the exact *opposite* of your patch:
make mutex_unlock() actively cause preemption after it has released
the lock but before it has done the final accesses.

                 Linus