I have been struggling for a few months with hard lock-ups when using
laptop-mode. Every 3-4 days, my laptop would freeze during the night,
with no message in the syslog, and for no apparent reason. The hard disk
activity light would always be on in the morning, which somehow made me
thing that it happened when the disk was started after an inactivity
period. Since I installed dbus and hald, the frequency increased to once
every night, which was a real pain. I don't think it has anything to do
with either dbus or hald, but they probably made the hard disk spin up
more often, therefore increasing the probability for the problem to happen.

Three days ago, I found this patch, which was accepted for 2.6.14, and
seems to work around a problem that sounds close enough:

  http://tinyurl.com/b3y2d

It applies cleanly to gentoo-sources-2.6.12-r10, which is what I'm
currently using. I quickly made an ebuild for it, attached below with
the patch from the address above.

Well, I don't like to shout victory too early, but I have had no crash
for the last three days, even with dbus and hald running.

Just thought this info might be interesting.
-- Remy


Remove underscore and suffix in reply address for a timely response.
# Copyright 1999-2005 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: $

ETYPE="sources"
K_WANT_GENPATCHES="base extras"
K_GENPATCHES_VER="14"
IUSE="ultra1"
inherit kernel-2 eutils
detect_version
detect_arch

KEYWORDS="amd64 ~ia64 ppc ppc64 ~sparc x86"

HOMEPAGE="http://dev.gentoo.org/~dsd/genpatches";

DESCRIPTION="Full sources including the gentoo patchset for the 
${KV_MAJOR}.${KV_MINOR} kernel tree"
SRC_URI="${KERNEL_URI} ${GENPATCHES_URI} ${ARCH_URI}"

pkg_setup() {
        if use sparc; then
                # hme lockup hack on ultra1
                use ultra1 || UNIPATCH_EXCLUDE="${UNIPATCH_EXCLUDE} 
1399_sparc-U1-hme-lockup.patch"
        fi
}

src_unpack() {
        kernel-2_src_unpack

        epatch "${FILESDIR}/ide-lockup.patch"
}

pkg_postinst() {
        postinst_sources

        echo

        if [ "${ARCH}" = "sparc" ]; then
                if [ x"`cat /proc/openprom/name 2>/dev/null`" \
                         = x"'SUNW,Ultra-1'" ]; then
                        einfo "For users with an Enterprise model Ultra 1 using 
the HME"
                        einfo "network interface, please emerge the kernel 
using the"
                        einfo "following command: USE=ultra1 emerge ${PN}"
                fi
        fi
        einfo "For more info on this patchset, and how to report problems, see:"
        einfo "${HOMEPAGE}"
}
From: Benjamin Herrenschmidt <[EMAIL PROTECTED]>
Date: Sun, 9 Oct 2005 00:37:47 +0000 (+1000)
Subject:     [PATCH] ide: Workaround PM problem
X-Git-Tag: v2.6.14-rc4
X-Git-Url: 
http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=867f8b4e47a17c5d68c98dc6eee12739c4490056

  [PATCH] ide: Workaround PM problem
  
  The logic in ide_do_request() doesn't guarantee that both drives will be
  serviced after a call.  It may "forget" to service one in some
  circumstances, including when one of the drive is suspended (it will
  eventually fail to service the slave when the master is suspended for
  example).  This prevents the wakeup requests that gets queued on wakeup
  from sleep from beeing serviced in some cases when 2 drives are sharing
  an IDE bus.
  
  The problem is deep enough in the way this code works (and there are
  probably a few other problematic but rare corner cases) and fixing it
  would require some major rethinking of the way IDE decides which channel
  to service.  This is not 2.6.14 material.  However, in the meantime,
  Bart has accepted this simple workaround that will fix the crash on
  wakeup from sleep since this specific corner case is actually hitting
  users to get into 2.6.14.
  
  Signed-off-by: Benjamin Herrenschmidt <[EMAIL PROTECTED]>
  Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
---

--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -1101,6 +1101,7 @@ static void ide_do_request (ide_hwgroup_
        ide_hwif_t      *hwif;
        struct request  *rq;
        ide_startstop_t startstop;
+       int             loops = 0;
 
        /* for atari only: POSSIBLY BROKEN HERE(?) */
        ide_get_lock(ide_intr, hwgroup);
@@ -1153,6 +1154,7 @@ static void ide_do_request (ide_hwgroup_
                        /* no more work for this hwgroup (for now) */
                        return;
                }
+       again:
                hwif = HWIF(drive);
                if (hwgroup->hwif->sharing_irq &&
                    hwif != hwgroup->hwif &&
@@ -1192,8 +1194,14 @@ static void ide_do_request (ide_hwgroup_
                 * though. I hope that doesn't happen too much, hopefully not
                 * unless the subdriver triggers such a thing in its own PM
                 * state machine.
+                *
+                * We count how many times we loop here to make sure we service
+                * all drives in the hwgroup without looping for ever
                 */
                if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & 
REQ_PREEMPT)) {
+                       drive = drive->next ? drive->next : hwgroup->drive;
+                       if (loops++ < 4 && !blk_queue_plugged(drive->queue))
+                               goto again;
                        /* We clear busy, there should be no pending ATA 
command at this point. */
                        hwgroup->busy = 0;
                        break;

Reply via email to