From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Subject: Re: Loud "pop" coming from hard drive on reboot Date: Wed, 18 Apr 2007 23:31:14 +0200 Message-ID: <200704182331.14515.bzolnier@gmail.com> References: <461D4E2C.6000704@redhat.com> <46254416.6090202@rtr.ca> <4625AF20.7050904@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from ug-out-1314.google.com ([66.249.92.168]:35776 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992714AbXDRVVR (ORCPT ); Wed, 18 Apr 2007 17:21:17 -0400 Received: by ug-out-1314.google.com with SMTP id 44so504695uga for ; Wed, 18 Apr 2007 14:21:16 -0700 (PDT) In-Reply-To: <4625AF20.7050904@gmail.com> Content-Disposition: inline Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Mark Lord , Chuck Ebbert , emisca , Jan Engelhardt , linux-kernel , linux-ide@vger.kernel.org, Adrian Bunk , Andrew Morton On Wednesday 18 April 2007, Tejun Heo wrote: > Mark Lord wrote: > > Chuck Ebbert wrote: > >> Mark Lord wrote: > >>> I'll patch it locally on my own machines, but what about the tens > >>> of thousands of other Seagate notebook drive owners out there? > >>> > >> > >> This is a problem with Seagate specifically, spinning back up > >> on receipt of some command after spindown? > > > > No, they just seem to be affected worse by it than some other brands. > > The bug is that libata/SCSI now spin-down the drive before the distro's > > scripts are done with it, so it spins down, and then gets spun up again > > by the distro, and then spun down again by the distro. > > > > And along the way, one/both of the two causes a full mechanism "park", > > which is hard on things if abused (like this). > > > > Or at least that's what I recall for it. Tejun? > > This really isn't a regression. It's been always like that with libata. Tejun, it is a regression over IDE subsystem (so all PATA and some SATA also). Dave/Chuck, this also seems like a FC7 regression (because of the libata PATA switch). > libata doesn't make devices go into standby mode and shutdown(8) does > it for libata. The problem here is that libata does issue > SYNCHRONIZE_CACHE on shutdown. So, the sequence of event is... > > 1. shutdown(8) issues SYNCHRONIZE_CACHE followed by STANDBY_NOW > 2. kernel shutdown starts > 3. libata shutdown issues SYNCHRONIZE_CACHE > 4. power goes off > > Some drives seem to spin up at step #3 even when its cache is clean and > power goes off right after the disk finishes the command. So, it's > really bad when it happens - spin down, spin up followed by immediate > power off. > > SCSI part of the fix is queued in scsi-misc-2.6 tree and libata-dev part > is acked and waiting to be merged, so the fix will be available in > 2.6.22. However, it's disabled by default to remain compatible with the > current behavior and requires userland change to fully fix the problem.