Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 4 Nov 2001 20:58:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 4 Nov 2001 20:58:46 -0500 Received: from gear.torque.net ([204.138.244.1]:47879 "EHLO gear.torque.net") by vger.kernel.org with ESMTP id ; Sun, 4 Nov 2001 20:58:25 -0500 Message-ID: <3BE5F238.6121972C@torque.net> Date: Sun, 04 Nov 2001 20:58:16 -0500 From: Douglas Gilbert X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.13 i686) X-Accept-Language: en MIME-Version: 1.0 To: Alan Cox CC: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Linux 2.4.13-ac7 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 Alan, I getting repeatable lockups on my SMP box (dual Celeron Abit hack) after sg does direct IO in this new version. This sequence using sg_rbuf from my sg3_utils package (www.torque.net/sg) locks at the end of the transfer just before returning: $ echo 1 > /proc/scsi/sg/allow_dio $ sg_rbuf -d -b=512 /dev/sg0 # /dev/sg0 is a fast disk. # this executes multiple READ BUFFER commands each 512 KB The box is still usable but the "sg_rbuf" process is unkillable and ps locks just before it would have listed the damaged process. Alt-SysRq-T shows that the sg_rbuf task in "D" state. The stack backtrace is: write_chan rwsem_down_write_failed ???? ret_from_fork This is with sg version 3.2.21 utilising alloc_kiovec_sz() and friend. I didn't see this "feature" when I tested it against ac4 before submitting it to you. Changing the "nbhs" value from 0 to 256 doesn't make any difference. I have just retested with ac4+sg3.1.21 and it works. When normal double buffering is used (i.e. no "-d" switch to the above sg_rbuf) there is no lockup. Doug Gilbert - 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/