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Wed, 28 Oct 2026 14:37:56 +0000 (UTC) Received: from onestero-thinkpadp1gen7.tpbc.csb (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id CD3A319560AB; Wed, 28 Oct 2026 14:37:53 +0000 (UTC) Received: by onestero-thinkpadp1gen7.tpbc.csb (nbSMTP-1.00) for uid 13628 oleg@redhat.com; Wed, 28 Oct 2026 15:37:55 +0100 (CET) Date: Wed, 28 Oct 2026 15:37:52 +0100 From: Oleg Nesterov To: Mani Tofigh via B4 Relay Cc: Andrew Morton , Christian Brauner , linux-mm@kvack.org, linux-kernel@vger.kernel.org, tz2294@columbia.edu, Mani Tofigh Subject: Re: [PATCH] exit: use READ_ONCE() to read mm->owner Message-ID: References: <20261027-kcsan-exit-v1-1-7c0429a29bc0@columbia.edu> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261027-kcsan-exit-v1-1-7c0429a29bc0@columbia.edu> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 10/27, Mani Tofigh via B4 Relay wrote: > > --- a/kernel/exit.c > +++ b/kernel/exit.c > @@ -494,7 +494,7 @@ void mm_update_next_owner(struct mm_struct *mm) > * If the exiting or execing task is not the owner, it's > * someone else's problem. > */ > - if (mm->owner != p) > + if (READ_ONCE(mm->owner) != p) Acked-by: Oleg Nesterov