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 6DCF7C25B7E for ; Tue, 28 May 2024 06:31:32 +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=Us0ikjG+JUxQxOWfW3Oh9bjGMp8p6F05tQTo8cWcwek=; b=gB8TKk1eFw6ORZcLJi3CoiNnmj qyQf4JfLYVUdNGGssnOZVj9aGiszPL9k+Y4AJDMkXjzclZLBDXoOp0ubnWY2ysMj1vUfb/9KBiqwy 1G0RAkPctZcJYSn/NgfFqHR5/zxY4fWwWV1qPSSjuyAi53D4awoux/Hst1qBPcVBAAPdfijiGT50H l74iUz4vqiZXGfemKA9sY3AlJWcdhk0v799796YN4FB1lCAiDk3OS4edq1b515IlYV/T+B4cncLBx vHRPpX/JlLmTwEodkxI3zOgxOhLrBey0Hm9uctixLgQ5UHLysJmAfHGVMVuC0m15unHDaWNqPg/3g vaXIeOog==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sBqMq-0000000HCgU-0x8z; Tue, 28 May 2024 06:31:28 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sBqMn-0000000HCeX-0u6K for linux-nvme@lists.infradead.org; Tue, 28 May 2024 06:31:26 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 6D36D67373; Tue, 28 May 2024 08:31:09 +0200 (CEST) Date: Tue, 28 May 2024 08:31:09 +0200 From: Christoph Hellwig To: Stuart Hayes Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , "Rafael J . Wysocki" , Tanjore Suresh , Martin Belanger , Oliver O'Halloran , Daniel Wagner , Keith Busch , Lukas Wunner , David Jeffery , Jeremy Allison , Jens Axboe , Christoph Hellwig , Sagi Grimberg , linux-nvme@lists.infradead.org Subject: Re: [PATCH v6 3/4] driver core: shut down devices asynchronously Message-ID: <20240528063109.GA29965@lst.de> References: <20240516154920.221445-1-stuart.w.hayes@gmail.com> <20240516154920.221445-4-stuart.w.hayes@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240516154920.221445-4-stuart.w.hayes@gmail.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240527_233125_490650_715EBAEB X-CRM114-Status: GOOD ( 12.83 ) 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 Thu, May 16, 2024 at 10:49:19AM -0500, Stuart Hayes wrote: > Add /sys/kernel/async_shutdown to allow user control of this feature: > > safe: shut down all devices synchronously, unless driver prefers async > shutdown (driver opt-in) (default) > on: shut down all devices asynchronously, unless disabled by the driver > (driver opt-out) > off: shut down all devices synchronously The on option seems very odd. IMHO safe is the only really sensible option, and maybe we have to support off as a bandaid due to userspace behavior dependent on synchronous shutdown, but I'd rather try even without that first.