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 46552C3600C for ; Thu, 3 Apr 2025 15:38:11 +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=7Paev1UznFISPdf7f3oQhQF6ucKiRzrhD7pWESqJzkE=; b=E9rjyr9Jjn3TlyyKnwG6WVdRQO y3CQ2tuLR2OzdZqyPNdFVUqdUnJGCJyPYdjgGYexEQVpu9HgI6MVXYU2YkYmlKsLdq9/Tv0bVAJVT EZVCQvAyj3EIDgqyNLhVLavWbMQnftGaSEGh+XHdhBvxKGD6YLiakzQO1jIO/XrLtec/H75dxMgEE iYiR1K5wVoNFKcMo2fRphRbhAjIP9syEkkuv5LjVX6oQPn4ruUMdXUeaQiProAWtJh/ZDNdodUWPH MLzpP4iFqOJruURQDEr8uK8Ryd9qyypOvAQaPHqASM3nMIup6PABT3l+1dWahMhrK4RJlSvpvIJ2i FsYEufYQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u0Mds-00000009FhA-2Lcr; Thu, 03 Apr 2025 15:38:08 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98.1 #2 (Red Hat Linux)) id 1u0MdZ-00000009Feo-1ABj for linux-nvme@lists.infradead.org; Thu, 03 Apr 2025 15:37:50 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id BAC9F5C621C; Thu, 3 Apr 2025 15:35:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 37449C4CEE3; Thu, 3 Apr 2025 15:37:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743694668; bh=9ZQNI4mqXE9vOVnXPFO4dyQGGBEqrf0Xx1uyjbvSvNY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=syaNVHiFrXWGM2YIRBQSwHWPQx6qx20w0/5fTu1FJ4lEn3L4HfiJW5PfQ+JlZFfWT M7XW0JyrzYPgTnWHinmrfHhmkr0b2hAQ4blF65EI/337dDlLLtVgySa+W6bGr2lVEa HNoyUVRVwu4+qXgQ/EO1h6lxT5oPbL0fNR/9o1q+c/6MB95RxUtCHbgc0vMzbRZi8u wNkPGeah7RcAlt2oskFDekyiP0F99Sre3O2Q1tdzwm/2Tr7wjNcwwD7nBVpq6XpxNr LuDFbUEPCgObEh97qV3r8dqwG5tMyOlvYbDHReEl3LisTe3UPSY9ClTDTJxnC37t/m F/wQg+Ssf3hdA== Date: Thu, 3 Apr 2025 09:37:46 -0600 From: Keith Busch To: Hannes Reinecke Cc: Hannes Reinecke , Christoph Hellwig , Sagi Grimberg , linux-nvme@lists.infradead.org Subject: Re: [PATCH 2/2] nvme: re-read ANA log page after ns scan completes Message-ID: References: <20250403071930.52154-1-hare@kernel.org> <20250403071930.52154-3-hare@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250403_083749_359692_B350CAF9 X-CRM114-Status: GOOD ( 16.50 ) 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, Apr 03, 2025 at 05:32:59PM +0200, Hannes Reinecke wrote: > On 4/3/25 16:55, Keith Busch wrote: > > On Thu, Apr 03, 2025 at 09:19:30AM +0200, Hannes Reinecke wrote: > > > When scanning for new namespaces we might have missed an ANA AEN, > > > so we should always re-read the ANA log page after scanning to ensure > > > we don't miss updates there. > > > > Worst case we might check a log page that hasn't changed. Rescans should > > be rare, so I guess it's fine. But I'm not sure why scanning might cause > > an ANA AEN to be missed. ? > Well, it's not that we're _missing_ AENs here. > As per quoted spec ANA change events are not sent if there had been > an event (on the controller) which would have caused both an ANA change > event and an NS changed AEN to be sent. > > So any NS changed event really needs to be treated as a combination of > NS changed _and_ ANA changed, and after each namespace rescan we need > to re-read the ANA log page. Oh, good call. I forgot about that text.