From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 98C971C68F for ; Fri, 4 Apr 2025 09:11:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743757917; cv=none; b=JItZAzSBfkpKr88burQQXy7dkwB444go0Hcws1Kh1oVAAdGzTOtQ831xpPOG/2fSKR0wBdNZfu0zg3MmAb3fe7enl9aUZPh0JG9NdAUK4+3KxN8svbDABcq/h6MxK3bZzJxOz75FaEhpSaQIxZLbOGTzV4jzQQ1fjsrbkabSOcA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743757917; c=relaxed/simple; bh=J5iD6faKud1jnZbcPPyRFQ7NuCZu+ZA2aWLrNkzF8TU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VXJqY16a2BeD1rgrF6yeDfEHx5N81I/b4XsHP0foukremRaO9uiRmm/p4Nw8v4Ozojk4SUV3D+FcoV/v79PO9sivEHd2EfS+EJXU5yr6e418ui8Zk5mjcVg/oBxqzUgfkjQ3xF0gfwhBINjvAnovTpBAYfdKSZi1GsDcAivOS3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id CF59A68C7B; Fri, 4 Apr 2025 11:11:50 +0200 (CEST) Date: Fri, 4 Apr 2025 11:11:49 +0200 From: Christoph Hellwig To: Ming Lei Cc: Jens Axboe , linux-block@vger.kernel.org, Nilay Shroff , Christoph Hellwig , syzbot+9dd7dbb1a4b915dee638@syzkaller.appspotmail.com Subject: Re: [PATCH] loop: replace freezing queue with quiesce when changing loop specific setting Message-ID: <20250404091149.GC12163@lst.de> References: <20250403105414.1334254-1-ming.lei@redhat.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250403105414.1334254-1-ming.lei@redhat.com> User-Agent: Mutt/1.5.17 (2007-11-01) On Thu, Apr 03, 2025 at 06:54:14PM +0800, Ming Lei wrote: > freeze queue should be used for changing block layer generic setting, such > as logical block size, PI, ..., and it is enough to quiesce queue for > changing loop specific setting. Why? A queue should generally be frozen for any setting affecting the I/O path. Nothing about generic or internal. This also misses an explanation of what setting this protects and why you think this is safe and the sound fix.