Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 7 Jan 2002 08:03:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 7 Jan 2002 08:03:01 -0500 Received: from e1.ny.us.ibm.com ([32.97.182.101]:63419 "EHLO e1.ny.us.ibm.com") by vger.kernel.org with ESMTP id ; Mon, 7 Jan 2002 08:02:52 -0500 Subject: Re: bug in IBM ServeRAID driver? To: Jens Axboe Cc: linux-kernel@vger.kernel.org, petter wahlman X-Mailer: Lotus Notes Release 5.0.7 March 21, 2001 Message-ID: From: "ServeRAID For Linux" Date: Mon, 7 Jan 2002 08:02:29 -0500 X-MIMETrack: Serialize by Router on D04NMS65/04/M/IBM(Release 5.0.8 |June 18, 2001) at 01/07/2002 08:02:29 AM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Sorry for the delayed response. We have been snow-bound and shut-down here for several days. We will address this immediately. Thanks for bringing it to our attention. Jens Axboe > cc: linux-kernel@vger.kernel.org, ServeRAID For Linux/Raleigh/IBM@IBMUS 01/03/2002 Subject: Re: bug in IBM ServeRAID driver? 03:06 PM On Thu, Jan 03 2002, petter wahlman wrote: > > While looking through linux-2.4.18pre1/drivers/scsi/ips.c I noticed that > a spin_lock_irq is held while doing a possibly blocking operation. > Can't this code livelock on SMP if datasize is set? > > linux-2.4.18pre1/drivers/scsi/ips.c > > 1778 /* reobtain the lock */ > 1779 spin_lock_irq(&io_request_lock); > 1780 > 1781 /* command finished -- copy back */ > 1782 user_area = *((char **) &SC->cmnd[4]); > 1783 kern_area = ha->ioctl_data; > 1784 datasize = *((u_int32_t *) &SC->cmnd[8]); > 1785 > 1786 if (datasize) { > 1787 if (copy_to_user(user_area, kern_area, datasize) > 0) { > 1788 DEBUG_VAR(1, "(%s%d) passthru failed - unable to > copy out user data", > 1789 ips_name, ha->host_num); > > > I am not subscribed to this list, so please CC me. Yup, that's surely a nasty bug. -- Jens Axboe - 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/