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 DD788C3814E for ; Sat, 6 Jul 2024 06:26:21 +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=vs99IsEPJnd/DIIZp9Fqs4KgTlBS2g+L1XvJ3jwXgxU=; b=pU3KY4f+6cw4ZA8cC8C6FcWpP8 IE49vzUm7nf31z/a4AcMb3qUThF543+qdd11wTLw1jekk5q/gtAH/DsnSANIQI32M/KhDikHm3urK ELqrIlCKd37fvj8y8hShMILif1efmAs8NwCmbLOAoAH+jxAe4GuYCTpsOgiYOZgY1l49kSilmuXsL ho2zf9zubZm6fjES+/v2gDpO7p/EJPZSnTLZxINzgad/hVgVjqq8Z3jKlEu0JfwOMP4bNW2Q/L0zb FgHhbmxCIVeTjTUbqAYN9Xv3apxnpejbwlR39qFBRIgW1+8kFA78Req6CpDpJitkPVeRheurpF6Gd vSZFm2cQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPysD-0000000HPtE-2z0M; Sat, 06 Jul 2024 06:26:17 +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 1sPysA-0000000HPsC-0RSy for linux-nvme@lists.infradead.org; Sat, 06 Jul 2024 06:26:15 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id AA8AA68D0E; Sat, 6 Jul 2024 08:26:04 +0200 (CEST) Date: Sat, 6 Jul 2024 08:26:04 +0200 From: Christoph Hellwig To: Chaitanya Kulkarni Cc: Christoph Hellwig , Leon Romanovsky , Jens Axboe , Jason Gunthorpe , Robin Murphy , Joerg Roedel , Will Deacon , Keith Busch , "Zeng, Oak" , Sagi Grimberg , Bjorn Helgaas , Logan Gunthorpe , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , Marek Szyprowski , =?iso-8859-1?B?Suly9G1l?= Glisse , Andrew Morton , "linux-block@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-rdma@vger.kernel.org" , "iommu@lists.linux.dev" , "linux-nvme@lists.infradead.org" , "linux-pci@vger.kernel.org" , "kvm@vger.kernel.org" , "linux-mm@kvack.org" Subject: Re: [RFC PATCH v1 00/18] Provide a new two step DMA API mapping API Message-ID: <20240706062604.GA13874@lst.de> References: <20240703054238.GA25366@lst.de> <20240703105253.GA95824@unreal> <20240703143530.GA30857@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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-20240705_232614_296496_7C99D8DA X-CRM114-Status: GOOD ( 15.03 ) 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 Fri, Jul 05, 2024 at 10:53:06PM +0000, Chaitanya Kulkarni wrote: > I tried to reproduce this issue somehow it is not reproducible. > > I'll try again on Leon's setup on my Saturday night, to fix that > case. It is passthrough I/O from userspace. The address is not page aligned as seen in the printk. Forcing bounce buffering of all passthrough I/O makes it go away. The problem is the first mapped segment does not have to be aligned and we're missing the code to places it at the aligned offset into the IOVA space.