Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756604AbZFBR6V (ORCPT ); Tue, 2 Jun 2009 13:58:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755131AbZFBR6N (ORCPT ); Tue, 2 Jun 2009 13:58:13 -0400 Received: from brick.kernel.dk ([93.163.65.50]:40434 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753555AbZFBR6M (ORCPT ); Tue, 2 Jun 2009 13:58:12 -0400 Date: Tue, 2 Jun 2009 19:58:14 +0200 From: Jens Axboe To: Andrew Morton Cc: scameron@beardog.cca.cpqcorp.net, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, mikem@beardog.cca.cpqcorp.net Subject: Re: [PATCH 2/2] cciss: Fix SCSI device reset handler Message-ID: <20090602175814.GO11363@kernel.dk> References: <20090527203007.GA30160@beardog.cca.cpqcorp.net> <20090529124208.531839fe.akpm@linux-foundation.org> <20090602125011.GJ11363@kernel.dk> <20090602105114.fe754481.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090602105114.fe754481.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2138 Lines: 61 On Tue, Jun 02 2009, Andrew Morton wrote: > On Tue, 2 Jun 2009 14:50:11 +0200 > Jens Axboe wrote: > > > On Fri, May 29 2009, Andrew Morton wrote: > > > On Wed, 27 May 2009 15:30:07 -0500 > > > scameron@beardog.cca.cpqcorp.net wrote: > > > > > > > +static int wait_for_device_to_become_ready(ctlr_info_t *h, > > > > + unsigned char lunaddr[]) > > > > +{ > > > > + int rc; > > > > + int count = 0; > > > > + int waittime = HZ; > > > > + CommandList_struct *c; > > > > + > > > > + c = cmd_alloc(h, 1); > > > > + if (!c) { > > > > + printk(KERN_WARNING "cciss%d: out of memory in " > > > > + "wait_for_device_to_become_ready.\n", h->ctlr); > > > > + return IO_ERROR; > > > > + } > > > > + > > > > + /* Send test unit ready until device ready, or give up. */ > > > > + while (count < 20) { > > > > + > > > > + /* Wait for a bit. do this first, because if we send > > > > + * the TUR right away, the reset will just abort it. > > > > + */ > > > > + set_current_state(TASK_INTERRUPTIBLE); > > > > + schedule_timeout(waittime); > > > > > > That's schedule_timeout_interruptible(). > > > > > > The problem with interruptible sleeps of this nature is that they are > > > no-ops if the calling process happens to have signal_pending(). I > > > suspect that this condition will break your driver. > > > > > > If so, switching to schedule_timeout_uninterruptible() will unbreak it. > > > > I added Stephens patch and your fixup. > > My cciss-fix-scsi-device-reset-handler-fix.patch was a simple cleanup - > it uses schedule_timeout_interruptible(). > > I believe that this should be changed to > schedule_timeout_uninterruptible() for the above reasons, but the cciss > guys fell asleep on me. It's an improvement, none the less. And I bet it should just be uninterruptible sleep, unless it has a good reason to accept signals. Mike? Stephen? -- 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/