From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757840Ab1GKVFc (ORCPT ); Mon, 11 Jul 2011 17:05:32 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:53501 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757576Ab1GKVFb (ORCPT ); Mon, 11 Jul 2011 17:05:31 -0400 Date: Mon, 11 Jul 2011 14:04:50 -0700 From: Andrew Morton To: scameron@beardog.cce.hp.com Cc: james.bottomley@hansenpartnership.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, stephenmcameron@gmail.com, thenzl@redhat.com, mikem@beardog.cce.hp.com Subject: Re: [PATCH] hpsa: do not attempt to read from a write-only register Message-Id: <20110711140450.a6f3e8be.akpm@linux-foundation.org> In-Reply-To: <20110711205124.GB25366@beardog.cce.hp.com> References: <20110708195926.3623.30375.stgit@beardog.cce.hp.com> <20110711131911.31789ee0.akpm@linux-foundation.org> <20110711205124.GB25366@beardog.cce.hp.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Jul 2011 15:51:24 -0500 scameron@beardog.cce.hp.com wrote: > On Mon, Jul 11, 2011 at 01:19:11PM -0700, Andrew Morton wrote: > > On Fri, 08 Jul 2011 14:59:26 -0500 > > "Stephen M. Cameron" wrote: > > > > > From: Stephen M. Cameron > > > > > > Most smartarrays tolerate it, but a few new ones don't. > > > > > > Signed-off-by: Stephen M. Cameron > > > --- > > > drivers/scsi/hpsa.h | 2 +- > > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > > > diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h > > > index 6d8dcd4..7f53cea 100644 > > > --- a/drivers/scsi/hpsa.h > > > +++ b/drivers/scsi/hpsa.h > > > @@ -214,7 +214,7 @@ static void SA5_submit_command(struct ctlr_info *h, > > > dev_dbg(&h->pdev->dev, "Sending %x, tag = %x\n", c->busaddr, > > > c->Header.Tag.lower); > > > writel(c->busaddr, h->vaddr + SA5_REQUEST_PORT_OFFSET); > > > - (void) readl(h->vaddr + SA5_REQUEST_PORT_OFFSET); > > > + (void) readl(h->vaddr + SA5_SCRATCHPAD_OFFSET); > > > h->commands_outstanding++; > > > if (h->commands_outstanding > h->max_outstanding) > > > h->max_outstanding = h->commands_outstanding; > > > > The changelog forgot to tell us the user-visible effects of the bug. > > That was really really bad of it. Bad changelog. No bone for you. > > Oh, sorry. When the controller doesn't tolerate the bug, the firmware > on it locks up. No interrupts are received, no commands complete. I/o > on that controller grinds to a halt. OK, that was important. Presumably you'd like those newer controllers to work with older kernels? In which case we should mark the patch for -stable backporting? I've done that to my copy and have updated the changelog. > I can resubmit if you like. I have two other needed-in-3.0 scsi patches. I'll send all three Jameswards now.