On Saturday August 30, david@xxxxxxxxxxxx wrote: > Rafael J. Wysocki wrote: > > This message has been generated automatically as a part of a report > > of recent regressions. > > > > The following bug entry is on the current list of known regressions > > from 2.6.26. Please verify if it still should be listed and let me know > > (either way). > > > > > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=11460 > > Subject : 2.6.27-rc3 to -rc4 regression: init 0 hangs in halt > > Submitter : David Greaves <david@xxxxxxxxxxxx> > > Date : 2008-08-30 04:07 (1 days old) > > Yes. > > I'm trying to bisect it but came across a bug/problem in git doing bisects. > (see message subject "setlocalversion wasn't producing git labels for bisect") Hi David. Could you please try this patch? Thanks, NeilBrown >From 271f5a9b8f8ae0db95de72779d115c9d0b9d3cc5 Mon Sep 17 00:00:00 2001 From: NeilBrown <neilb@xxxxxxx> Date: Mon, 1 Sep 2008 12:32:52 +1000 Subject: [PATCH] Remove invalidate_partition call from do_md_stop. When stopping an md array, or just switching to read-only, we currently call invalidate_partition while holding the mddev lock. The main reason for this is probably to ensure all dirty buffers are flushed (invalidate_partition calls fsync_bdev). However if any dirty buffers are found, it will almost certainly cause a deadlock as starting writeout will require an update to the superblock, and performing that updates requires taking the mddev lock - which is already held. This deadlock can be demonstrated by running "reboot -f -n" with a root filesystem on md/raid, and some dirty buffers in memory. All other calls to stop an array should already happen after a flush. The normal sequence is to stop using the array (e.g. umount) which will cause __blkdev_put to call sync_blockdev. Then open the array and issue the STOP_ARRAY ioctl while the buffers are all still clean. So this invalidate_partition is normally a no-op, except for one case where it will cause a deadlock. So remove it. This patch possibly addresses the regression recored in http://bugzilla.kernel.org/show_bug.cgi?id=11460 and http://bugzilla.kernel.org/show_bug.cgi?id=11452 though it isn't yet clear how it ever worked. Signed-off-by: NeilBrown <neilb@xxxxxxx> --- drivers/md/md.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 8cfadc5..4790c83 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3841,8 +3841,6 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open) del_timer_sync(&mddev->safemode_timer); - invalidate_partition(disk, 0); - switch(mode) { case 1: /* readonly */ err = -ENXIO; -- 1.5.6.5 -- To unsubscribe from this list: send the line "unsubscribe kernel-testers" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
