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 4CE02D637A3 for ; Wed, 13 Nov 2024 18:06:09 +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=LQsAEfO1InkyeYqLO+agj8KVBnpzFdAGBOZc3/E45KI=; b=SI8S+Yae3GQ68+5vJIn5H7SHKG am7qS+cG4UqtSBV9YHbndp3XvBsZquwIaOGTvIdyFCye0t/UN6ssb4VmFUldPQL0NRV2t63fK4kM+ jbSAhMG33GLPCwI0uZ8DXbOAolmkG7iG0NsLGNjj1pdFk9ZqbNxMj1V1Smck91Jvirx5TDkgOZFV1 hghmlraASUdL5DOVHi56whzMOTA+wu/34mI386Y4wfQqkIkGOIzw44R+oPIpvaNlxU2pPOrsTXpri wcJmKlR74XZR19thi+Zbg9mf63Ub3FugSsh/CzjhAITvlh8Rb3zzSbOdKz2R6c79ZWFtBaPYvDxKF EMhV6aFw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tBHkk-00000007ekX-2DWM; Wed, 13 Nov 2024 18:06:06 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tBHkb-00000007eiz-1qAJ for linux-nvme@lists.infradead.org; Wed, 13 Nov 2024 18:05:58 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 16780A40FC7; Wed, 13 Nov 2024 18:04:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49B17C4CEC3; Wed, 13 Nov 2024 18:05:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731521155; bh=M4wyj6LnteCS8V5uLYewkH2xB3uFMsAbftOFpnkE21o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qmU33Ybq9mi6SS/EE9oMZnsYv/MW590U1NZ6DxaVzwGisRddMa9zzuYeFryV5QtDS QB1Jv6vnxMOSX5rBYRXUqOS6FowHhQT1bMVks5xuW99pozRML8wnXm4cFG85NjdzGN sSR7950AR4zd0WyLKTM/ulQ6dCiEyE19aEd+Fqdv8YjBgrrSbxG4SmYYkHVKZ+jLPL QrGdHEHKhxHtF1dkNEOcyR/ReyBh3o55WrDgYoW81e58yM1/+deuQylQTwfAfAIBql TRMEGUxOOiXKAwXkIx2XewWgBGCMPTERne0Kawf5CReHfULXbSqWrCv7oHRXgESeIY 4w6lf8eusXQeA== Date: Wed, 13 Nov 2024 11:05:53 -0700 From: Keith Busch To: Christoph Hellwig Cc: Bob Beckett , Jens Axboe , Sagi Grimberg , kernel@collabora.com, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] nvme-pci: 512 byte aligned dma pool segment quirk Message-ID: References: <20241112195053.3939762-1-bob.beckett@collabora.com> <20241113043151.GA20077@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241113043151.GA20077@lst.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241113_100557_582080_C778143E X-CRM114-Status: GOOD ( 16.56 ) 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 Wed, Nov 13, 2024 at 05:31:51AM +0100, Christoph Hellwig wrote: > On Tue, Nov 12, 2024 at 07:50:00PM +0000, Bob Beckett wrote: > > From: Robert Beckett > > > > We initially put in a quick fix of limiting the queue depth to 1 > > as experimentation showed that it fixed data corruption on 64GB > > steamdecks. > > > > After further experimentation, it appears that the corruption > > is fixed by aligning the small dma pool segments to 512 bytes. > > Testing via desync image verification shows that it now passes > > thousands of verification loops, where previously > > it never managed above 7. > > As suggested before, instead of changing the pool size please just > always use the large pool for this device. Well, he's doing what I suggested. I thought this was better because it puts the decision making in the initialization path instead of the IO path.