From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 1 Apr 2003 15:58:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 1 Apr 2003 15:58:25 -0500 Received: from e34.co.us.ibm.com ([32.97.110.132]:64935 "EHLO e34.co.us.ibm.com") by vger.kernel.org with ESMTP id ; Tue, 1 Apr 2003 15:58:23 -0500 Date: Tue, 01 Apr 2003 12:59:46 -0800 From: "Martin J. Bligh" Reply-To: linux-kernel To: linux-kernel Subject: [Bug 530] New: dma not enabled for IDE hard drives Message-ID: <137350000.1049230786@flay> X-Mailer: Mulberry/2.1.2 (Linux/x86) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org http://bugme.osdl.org/show_bug.cgi?id=530 Summary: dma not enabled for IDE hard drives Kernel Version: 2.5.66 Status: NEW Severity: normal Owner: bugme-janitors@lists.osdl.org Submitter: freelsjd@ornl.gov Distribution: Debian/Sid Hardware Environment: dual 2.4Ghz Xeon, SE7500CW2 MB, all Intel Promise PDC20267 ATA-100 ide channels in non-RAID mode Software Environment: testing with hdparm 5.2-1 of Debian/Sid Problem Description: I have similar .config settings for both the 2.4.20 and the 2.5.66 kernels with the identical machine. Under 2.4.20, I do get dma enabled and see good performance (Mb/s) from the hard disk I/O. However, under the 2.5.66 kernel, dma is not enabled and the performance of the hard drives is poor (~2-3 Mb/s under 2.4.20 versus ~30 Mb/s under 2.5.66). The "hdparm -I /dev/hda" command confirms that dma is not enabled under 2.5.66, but is under 2.4.20. Steps to reproduce: