From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] SATA: Blacklist systems that spin off disks during ACPI power off Date: Mon, 08 Sep 2008 13:38:12 +0200 Message-ID: <48C50EA4.2020700@gmail.com> References: <200808290002.55026.rjw@sisk.pl> <200808291241.04183.rjw@sisk.pl> <48B7D286.7050104@gmail.com> <200809061923.29020.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-2 Content-Transfer-Encoding: 7bit Return-path: Received: from ti-out-0910.google.com ([209.85.142.184]:41701 "EHLO ti-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751750AbYIHLjk (ORCPT ); Mon, 8 Sep 2008 07:39:40 -0400 Received: by ti-out-0910.google.com with SMTP id b6so896220tic.23 for ; Mon, 08 Sep 2008 04:39:37 -0700 (PDT) In-Reply-To: <200809061923.29020.rjw@sisk.pl> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: ACPI Devel Maling List , linux-ide@vger.kernel.org, Thomas Renninger , Robert Hancock , LKML , Frans Pop , Maciej Rutecki , Jeff Garzik , Andrew Morton Rafael J. Wysocki wrote: > SATA: Blacklist systems that spin off disks during ACPI power off > > Some notebooks from HP have the problem that their BIOSes attempt to > spin down hard drives before entering ACPI system states S4 and S5. > This leads to a yo-yo effect during system power-off shutdown and the > last phase of hibernation when the disk is first spun down by the > kernel and then almost immediately turned on and off by the BIOS. > This, in turn, may result in shortening the disk's life times. > > To prevent this from happening we can blacklist the affected systems > using DMI information. However, only the on-board controlles should > be blacklisted and their PCI slot numbers can be used for this > purpose. Unfortunately the existing interface for checking DMI > information of the system is not very convenient for this purpose, > because to use it, we would have to define special callback functions > or create a separate struct dmi_system_id table for each blacklisted > system. > > To overcome this difficulty introduce a new function > dmi_first_match() returning a pointer to the first entry in an array > of struct dmi_system_id elements that matches the system DMI > information. Then, we can use this pointer to access the entry's > .driver_data field containing the additional information, such as > the PCI slot number, allowing us to do the desired blacklisting. > > Introduce a new libata flag ATA_FLAG_NO_POWEROFF_SPINDOWN that, if > set, will prevent disks from being spun off during system power off > and hibernation (to handle the hibernation case we need a new system > state SYSTEM_HIBERNATE_ENTER that can be checked against by libata, > in analogy with SYSTEM_POWER_OFF). Use dmi_first_match() to set this > flag for some systems affected by the problem described above (HP nx6325, > HP nx6310, HP 2510p). > > Signed-off-by: Rafael J. Wysocki libata part looks good to me but I think it would be better to separate out DMI changes into a separate patch. Thanks. -- tejun