From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F6C8606A327 for ; Tue, 27 Oct 2026 15:10:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=shYZQ0RI; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=NlgoRxf8 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-Unsubscribe-Post:List-Owner; bh=bGUHLo03oq3Gg6IVQNN1cHzDG9J9sP8CXjYjZOjweHI=; b=shYZQ0RIrPfSOvBRLAA2D5Z4E3 TeA4Q0INbOxW1m9qWZgS+o2c/PcbneVGVrYWHRc0okQO80mz0+ojqN+3z9w5MpjynEBuQb9yv+BHb qkoiJNTP+NFoC+p2ZOHbldxIOeUmsLBYXiW2U7VsaoGL+ERGqnUIhmXl6cIzrkkSJ9VAfk1DsIaHy nSL00elprYzVekVr8PC6J5j29B/Yn+9nFuKLlhgf2sxdTUPUuzy3fOCsrjQ/YgHTVNfCzjd5coynQ fl8qXSrY/NFD6kA3r6xRmL00vIW6rlaEDD9VXBQBEVg7P4wIquP8ZZgfBuzF12bltJqIN+Vg4ZOWt Z9vomO7Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLip2-0000000581W-1UCE; Tue, 27 Oct 2026 15:10:44 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLip1-0000000581J-3pPc for linux-nvme@lists.infradead.org; Tue, 27 Oct 2026 15:10:43 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 5090C4347A; Tue, 27 Oct 2026 15:10:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DD3C21F01825; Tue, 27 Oct 2026 15:10:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793113843; bh=bGUHLo03oq3Gg6IVQNN1cHzDG9J9sP8CXjYjZOjweHI=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=NlgoRxf87R/lLIP0gRhuPMXw/9sgsDkuP/OhS5aUb/IVv1l/p4i0htoNayF+FaqZR d13p+lhI5IL/I3dQrD/BavcyILToAZuhVSW286rV2gKLuzsnk/8m2LmaDNlFCOyFWv r+oNQ6EXCM4qyame8jUiH0dVfmkI9YL+c4McEBB5d+fcVZxWBFVFaljE1FpCE+1jNC tz+999OOWLUya2pDjd7BDj0vFxrJLNhKcUonAzRppX7k2vxRbmu8DMyKM53zkwWYqO 7xMOje5tDI0i6pXnvp2YPaidAb0gi2rWE5PHl9UsIR9i3XwiLyBI5k3LDxykAufg35 Xjd0D8JzIarUA== Date: Tue, 27 Oct 2026 09:10:41 -0600 From: Keith Busch To: guzebing Cc: axboe@kernel.dk, sagi@grimberg.me, leon@kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Guzebing Subject: Re: [PATCH] nvme-pci: unmap the full IOVA range on PRP setup failure Message-ID: References: <20261027115718.2241149-1-guzebing1612@gmail.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261027115718.2241149-1-guzebing1612@gmail.com> X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" X-Spam-Status: No, score=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Tue, Oct 27, 2026 at 07:57:18PM +0800, guzebing wrote: > When using IOVA, blk_rq_dma_map_iter_start() maps the entire request > before PRP construction begins. However, iod->total_len is accumulated > as PRPs are populated. If a PRP list allocation fails, nvme_unmap_data() > passes this partial length to blk_rq_dma_unmap(), leaving part of the > request's DMA mapping intact. > > Use dma_iova_size() as the unmap length for IOVA mappings so that > cleanup covers the full range mapped by blk_rq_dma_map_iter_start(), > even when PRP construction fails. I don't think this is right. The dma state's iova size was set when it was allocated, but there are failure scenarios where we've only linked part of the request. I think the iod's total_len is just not in sync with the pinned mappings. We should update the total_len as we iterate the blk_mq_dma_iter, not when we've assigned a PRP element.