Re: 2.6.17-rc4 md lock held at task exit

[Keith Owens <kaos@ocs.com.au>]

Neil Brown (on Fri, 12 May 2006 17:11:11 +1000) wrote:
>On Friday May 12, kaos@ocs.com.au wrote:
>> Doing poweroff on 2.6.17-rc4 i386, SMP
>> 
>> BUG halt/4781, lock held at task exit time!
>>  [f7001b34] {mddev_find}
>> .. held by: halt: 4781 [f7cd4030, 118]
>> ... acquired at: md_notify_reboot+0x3a/0xa9 [md_mod}
>> 
>
>I suspect this will fix it.
>Is it repeatable?  Can you test?
>
>Thanks,
>NeilBrown
>
>
>Signed-off-by: Neil Brown <neilb@suse.de>
>
>### Diffstat output
> ./drivers/md/md.c |    4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
>diff ./drivers/md/md.c~current~ ./drivers/md/md.c
>--- ./drivers/md/md.c~current~	2006-05-12 16:00:03.000000000 +1000
>+++ ./drivers/md/md.c	2006-05-12 17:10:16.000000000 +1000
>@@ -5171,8 +5171,10 @@ static int md_notify_reboot(struct notif
> 		printk(KERN_INFO "md: stopping all md devices.\n");
> 
> 		ITERATE_MDDEV(mddev,tmp)
>-			if (mddev_trylock(mddev))
>+			if (mddev_trylock(mddev)) {
> 				do_md_stop (mddev, 1);
>+				mddev_unlock(mddev);
>+			}
> 		/*
> 		 * certain more exotic SCSI devices are known to be
> 		 * volatile wrt too early system reboots. While the

Finally got some time to test this.  The problem was reproducable and
the patch fixed it.

Acked-by: Keith Owens <kaos@ocs.com.au>