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From: "Cen Zhang (Microsoft)" <cenzhang@linux.microsoft.com>
To: Cen Zhang <cenzhang@linux.microsoft.com>
Cc: AutonomousCodeSecurity@microsoft.com,
	Christian Brauner <brauner@kernel.org>,
	Davidlohr Bueso <dave@stgolabs.net>,
	David Howells <dhowells@redhat.com>,
	Kees Cook <kees@kernel.org>,
	linux-kernel@vger.kernel.org,
	stable@vger.kernel.org,
	tgopinath@linux.microsoft.com,
	"Dae R. Jeong" <threeearcat@gmail.com>
Subject: Re: [PATCH] watch_queue: Fix missing locking in watch_queue_set_size()
Date: Thu,  8 Oct 2026 23:59:13 -0400
Message-ID: <20261009035913.73056-1-cenzhang@linux.microsoft.com>
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> +	/* Use lock since watches may already be attached. */
> +	spin_lock_bh(&wqueue->lock);
>  	wqueue->notes = pages;
>  	wqueue->notes_bitmap = bitmap;
>  	wqueue->nr_pages = nr_pages;
>  	wqueue->nr_notes = nr_notes;
> +	spin_unlock_bh(&wqueue->lock);

I'll send a v2 tomorrow, replacing the lock with smp_store_release()/
smp_load_acquire() for wqueue->nr_notes.