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 DE5B2C54E41 for ; Tue, 5 Mar 2024 13:51:08 +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=zbyBuPH7rwWudDBW1Y2OSxPts/ZpPphHYIN9AJqs06w=; b=fMu1Oa6xubEZdSnBWEdP68SCKe X3s3yL+pN6lBFHXq5NvClnISpiALAdkUgiwjyScOmeE3YIqIjQKB4F6QlSZBHpj2TPqdTLgqcvCaU ex6lvWQ/Sk8B7/tu0Wv29uHIbEgXxvFSTLLQU/ba9RJ60XX72tcM2uC0qOv49YmJkqzVLHgaztQ7M Z7RDp7ryI/q0A7JGiMk6Ve9xFuwqdlNNg1ez1GbGRD7r4h56OHMz8mOrQ93ghAIt6/LLYa6cqdozK 8jZH+A/ntTTCzuse0mNRwpUxdXvh0j2ITTeZZvMs7LcITC6UPi4kBRly6F/Ug4F10muwGb7cTJ8hf 6cPuqNsQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rhVCG-0000000DtnS-1j3h; Tue, 05 Mar 2024 13:51:08 +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 1rhVCC-0000000Dtme-3Tay for linux-nvme@lists.infradead.org; Tue, 05 Mar 2024 13:51:06 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 4748368C7B; Tue, 5 Mar 2024 14:51:00 +0100 (CET) Date: Tue, 5 Mar 2024 14:51:00 +0100 From: Christoph Hellwig To: Michael Kropaczek Cc: linux-nvme@lists.infradead.org, Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg Subject: Re: [PATCH v2 0/1] nvme: Fix problem when booting from NVMe drive was leading to a hang. Message-ID: <20240305135100.GC2063@lst.de> References: <20240304182507.2601387-1-michael.kropaczek@solidigm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240304182507.2601387-1-michael.kropaczek@solidigm.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-20240305_055105_351263_36F9D942 X-CRM114-Status: GOOD ( 17.88 ) 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, Mar 04, 2024 at 10:25:07AM -0800, Michael Kropaczek wrote: > Description: > > During endurance test, when a system was rebooted from NVMe drive, boot > process hung occasionally. The number of reboot cycles was set to 1000, > with interval of 120s. Hang occurred after ~300 reboot cycles. > After investigating the cause, it was established that NVMe driver > did not disable host memory during shutdown leaving NVMe controller > in a state preventing proper initialization in BIOS pre-boot stage. > Adding of the call to nvme_set_host_mem(dev, 0) when in shutdown > fixed the issue. Something odd is going on with your patch submissions, as you seem to send a single mail with a cover letter and the actual patch. That's why I missed the last one as I've been waiting for the actual patch mail which never arrived. > + /* > + * On certain host architectures/HW, DRAM was keeping memory contents over reboot-cycles. > + * It was observed that certain controllers were accessing host memory after > + * resetting which led to undefined state preventing proper initialization. > + */ Block comments should never span 80 characters. But more importantly I don't even think we need this comment at all, this is a clear bug fix and the code is self-describing.