Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756289AbXERMam (ORCPT ); Fri, 18 May 2007 08:30:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754545AbXERMaf (ORCPT ); Fri, 18 May 2007 08:30:35 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:36303 "EHLO the-village.bc.nu" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754370AbXERMaf (ORCPT ); Fri, 18 May 2007 08:30:35 -0400 Date: Fri, 18 May 2007 13:34:56 +0100 From: Alan Cox To: Robert Hancock Cc: Zoltan Boszormenyi , Peer Chen , linux-kernel Subject: Re: [PATCH] drivers/ata: Add the SW NCQ support to sata_nv for MCP51/MCP55/MCP61 Message-ID: <20070518133456.5f1392e9@the-village.bc.nu> In-Reply-To: <464D0855.20703@shaw.ca> References: <464D0855.20703@shaw.ca> X-Mailer: Claws Mail 2.9.1 (GTK+ 2.10.8; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 661 Lines: 13 > That shouldn't be a problem, libata default DMA mask is 32 bits (which > isn't overridden with this controller) and so the block layer will > bounce any data being read/written above that point with IOMMU or > swiotlb. The comment is a bit unnecessarily scary. Adding a BUG_ON for this would be wise. Its trivial to check and a BUG rather than corruption if this assumption ever changes would be far preferable - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/