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 A7C0DCD4F54 for ; Thu, 28 May 2026 18:19:22 +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=9zfQVtS7zyt1UNfdGE5qkvygfJ2lT/N6CFtv5qKDbrk=; b=r0uLMiSZAXFs572gaFT1Vbbgdj Vng7g2O3TsJ8I0GrenRY1isFgiF6AQOBYixb4v/VudOLIB21/7Y8VKWaZXmgvppcaUnh3gXojfL+C soUrcl4jxcNtIuKHWmG5htakCmeAy9jNIyPvyBKvW1gfdkcP/8PZioQRuNfNO9CW6BP9Ebj9e9X7P GXgCki6A4DfO5SKXmoqOLhUakrEjtVYm5h2PasQNLZrIOAp33bM71LOxJX8zFqUiakXzbL4f3fqp1 muY6Bx90ftAGpCWqg4vlDVswKJ8FqhvyjYBpBudWdfd01mVRFNQcUXDv6sOUvP3tLB3tiw+keqeAK C2kidJYg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wSfKA-00000006ArV-2AaP; Thu, 28 May 2026 18:19:18 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wSfK7-00000006Aqz-32s6 for linux-nvme@lists.infradead.org; Thu, 28 May 2026 18:19:16 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id B8E1840B4B; Thu, 28 May 2026 18:19:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 129971F000E9; Thu, 28 May 2026 18:19:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779992354; bh=9zfQVtS7zyt1UNfdGE5qkvygfJ2lT/N6CFtv5qKDbrk=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=CHnvxN+XbVHln5GN22bEU2DwuYKOLZj5zBnsHY7uYUJYtgLStmeZBgZI5iwEAeoW1 UAbb/TmzhPagoPnMxqDC+j24wYy4VtfZLogzWU+I02dzskNiBT8x+Qup1QHfOfxITg y1zvbhEtk8nC1CC6cShHaV9Tf5lTGv/kbLlo8IIIEv8n7OMr1Yih2MhyE7BBYZDQd7 9Bx5yLx0o8OqL++j+d1zBEZe7Y32uxEfJbTBpLLTIQEm88e//aJVSY3/NzghQ8aQ04 oN/m/MgPw6HKU9YTWqkjT/3xFKNI+GTJDRsWKBSh6kQoqXkdY6WEWD+Oj/swFOSZtQ KtSwbX2gFC35A== Date: Thu, 28 May 2026 12:19:12 -0600 From: Keith Busch To: "Achkinazi, Igor" Cc: "hch@lst.de" , "sagi@grimberg.me" , "axboe@kernel.dk" , "linux-nvme@lists.infradead.org" , "linux-block@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: Re: [PATCH v2] nvme-multipath: set BIO_REMAPPED on bios remapped to per-path namespace disks Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260528_111915_792241_7B41D92A X-CRM114-Status: GOOD ( 10.50 ) 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 28, 2026 at 03:24:27PM +0000, Achkinazi, Igor wrote: > The SRCU read lock prevents synchronize_srcu() from completing, but > does not prevent set_capacity(0) from executing. The bio fails the > EOD check before it reaches the NVMe driver, so nvme_failover_req() > never gets a chance to redirect it to another path of multipath. IO errors > are reported to the application despite another path being available. I double checked the sequences here, and yes, I think the synchronize_srcu's already in place ensure every caller sees the EOD error before it could fail the bio_queue_enter(), so this looks like it happens to be sufficient. I'm okay with it.