From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D3C20E77188 for ; Tue, 7 Jan 2025 00:45:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=B2ow3WPU9nS00Hk+pQzwgzy+yTO/847uxs0UlW6oZME=; b=x4/djDDMBh0mLNRZZrqpQAcdI3 KxzWd59IBQSCevDZcUAbAhKYpUTDqm7igkecIirsuUSaDc3McqmDc2ej4fmujLAkNNPDOrI5wuWs+ pfXHDJjv0pjZJxiUnuhUzbTyUiImMc9Ji5fOMS5dHflw3PFceSJmi4m4BxrIBdsSHAp3JkZ5eUDd1 TeZazwEfwaxfhUO7VkyT3u1A2Cmmnhw2WfGBftZ2wyowceDPJXYJXok/QCgBdi7zwmmHDuD7wzEjl ESzq5/n/bxzDAmvHn+8bIMfyfk8i/kmHg+ZDtsplOuenK6E1GgUwIQgX8ki2BYlNEeqcuyesapJeQ DkCtAVqw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tUxiy-0000000343B-11k4; Tue, 07 Jan 2025 00:45:36 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tUxit-0000000342P-0R2v for linux-nvme@lists.infradead.org; Tue, 07 Jan 2025 00:45:34 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1736210729; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=B2ow3WPU9nS00Hk+pQzwgzy+yTO/847uxs0UlW6oZME=; b=FAxPdJ1LOV1uGkteecqxt8PkYnCrxxYb1q1oyRKhzqFP1BXvRPYqgUq59U1QxLzWFZPTbX yeXdWnH/HK2O3Pc0E+r9Blk5rFVJRvlqEQialAbmPmdQKlJP0iqVq8IVAbd/9PPqTFnNKF p8RGyOIgRDmRcKuZ/s+ihQGK4xi2Clw= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-487-57ER_xUgNEOOYM1u31EC0g-1; Mon, 06 Jan 2025 19:45:26 -0500 X-MC-Unique: 57ER_xUgNEOOYM1u31EC0g-1 X-Mimecast-MFC-AGG-ID: 57ER_xUgNEOOYM1u31EC0g Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id AEC8919560B2; Tue, 7 Jan 2025 00:45:23 +0000 (UTC) Received: from fedora (unknown [10.72.116.43]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id AC74519560A2; Tue, 7 Jan 2025 00:45:17 +0000 (UTC) Date: Tue, 7 Jan 2025 08:45:11 +0800 From: Ming Lei To: Christoph Hellwig Cc: Damien Le Moal , Jens Axboe , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, Keith Busch , Sagi Grimberg , Nilay Shroff Subject: Re: [PATCH 1/3] block: Fix sysfs queue freeze and limits lock order Message-ID: References: <20250104132522.247376-1-dlemoal@kernel.org> <20250104132522.247376-2-dlemoal@kernel.org> <20250106082902.GC18408@lst.de> <20250106152931.GC27431@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250106152931.GC27431@lst.de> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250106_164531_229008_DD60FF33 X-CRM114-Status: GOOD ( 21.33 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Mon, Jan 06, 2025 at 04:29:31PM +0100, Christoph Hellwig wrote: > On Mon, Jan 06, 2025 at 07:15:27PM +0800, Ming Lei wrote: > > On Mon, Jan 06, 2025 at 09:29:02AM +0100, Christoph Hellwig wrote: > > > On Mon, Jan 06, 2025 at 11:31:43AM +0800, Ming Lei wrote: > > > > As I mentioned in another thread, freezing queue may not be needed in > > > > ->store(), so let's discuss and confirm if it is needed here first. > > > > > > > > https://lore.kernel.org/linux-block/Z3tHozKiUqWr7gjO@fedora/ > > > > > > We do need the freezing. What you're proposing is playing fast and loose > > > which is going to get us in trouble. > > > > It is just soft update from sysfs interface, and both the old and new limits > > are correct from device viewpoint. > > > > What is the trouble? We have run the .store() code without freezing for > > more than 10 years, no one report issue in the area. > > No, we had various bug reports due to it, including racing with other > updates. Let's stop trying to take shortcuts that will byte us again > later and sort this out properly. Can you share the bug reports? I am curious how it happen. Thanks, Ming