Re: [Bugme-new] [Bug 10061] New: Hang in md5_resync

Re: [Bugme-new] [Bug 10061] New: Hang in md5_resync

[Andrew Morton]

(please respond via emailed reply-to-all, not via the bugzilla web
interface, thanks)

On Thu, 21 Feb 2008 13:13:13 -0800 (PST) bugme-daemon@bugzilla.kernel.org wrote:

> http://bugzilla.kernel.org/show_bug.cgi?id=10061
> 
>            Summary: Hang in md5_resync
>            Product: IO/Storage
>            Version: 2.5
>      KernelVersion: 2.6.25-rc2
>           Platform: All
>         OS/Version: Linux
>               Tree: Mainline
>             Status: NEW
>           Severity: normal
>           Priority: P1
>          Component: MD
>         AssignedTo: io_md@kernel-bugs.osdl.org
>         ReportedBy: sgunderson@bigfoot.com
> 
> 
> Latest working kernel version: 2.6.23
> Earliest failing kernel version: 2.6.25-rc2
> Distribution: Debian unstable
> Hardware Environment: sata_nv, ext3, Seagate SATA disks 
> Software Environment: N/A
> Problem Description: After upgrading to 2.6.25, I did some light I/O (basically
> a tab-complete in my home directory), and the whole machine promptly hung.
> After a while, the serial console spat out:
> 
> [  548.684064] BUG: soft lockup - CPU#1 stuck for]
> [  548.684065] CPU 1:
> [  548.684065] Modules linked in: tun eeprom ide_generic ide_disk ide_cd_mod
> cdx
> [  548.684065] Pid: 3599, comm: md4_resync Not tainted 2.6.25-rc2 #1
> [  548.684065] RIP: 0010:[<ffffffff802fee07>]  [<ffffffff802fee07>]
> __write_loc0
> [  548.684065] RSP: 0018:ffff81011fcffc18  EFLAGS: 00000287
> [  548.684065] RAX: ffff81011c14dfd8 RBX: ffff8100d42d30c0 RCX:
> ffff8100d42d30c0
> [  548.684065] RDX: 0000000000000000 RSI: ffff8100d4cd0d90 RDI:
> ffff8100d4cd0d00
> [  548.684065] RBP: ffff81011fcffb90 R08: 00000000fe538a93 R09:
> 0000000000000000
> [  548.684065] R10: 00000000000000c0 R11: ffffffff803ad3e1 R12:
> ffffffff8020bcb6
> [  548.684065] R13: ffff81011fcffb90 R14: ffff8100d4cd0d00 R15:
> 0000000000000000
> [  548.684065] FS:  00007f8748e0c6e0(0000) GS:ffff81011fcb5dc0(0000)
> knlGS:00000
> [  548.684065] CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
> [  548.684066] CR2: 00007f8748e076f3 CR3: 00000000d296b000 CR4:
> 00000000000006e0
> [  548.684066] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> 0000000000000000
> [  548.684066] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
> 0000000000000400
> [  548.684066]
> [  548.684066] Call Trace:
> [  548.684066]  <IRQ>  [<ffffffff80446fe4>] ? _write_lock_bh+0x1a/0x1c
> [  548.684066]  [<ffffffff803ad49e>] ? neigh_resolve_output+0xbd/0x281
> [  548.684066]  [<ffffffff80407ab5>] ? ip6_output+0xc5c/0xc71
> [  548.684066]  [<ffffffff8039d414>] ? sock_alloc_send_skb+0x93/0x1e1
> [  548.684066]  [<ffffffff8041685b>] ? __ndisc_send+0x3c6/0x4fb
> [  548.684066]  [<ffffffff880a431a>] ? :sd_mod:sd_prep_fn+0x74/0x6fb
> [  548.684066]  [<ffffffff8041725b>] ? ndisc_send_ns+0x71/0x7e
> [  548.684066]  [<ffffffff80363c3c>] ? scsi_request_fn+0x339/0x3a5
> [  548.684066]  [<ffffffff804181df>] ? ndisc_solicit+0x159/0x166
> [  548.684066]  [<ffffffff80235673>] ? __mod_timer+0xb0/0xbf
> [  548.684066]  [<ffffffff803adc72>] ? neigh_timer_handler+0x292/0x2d0
> [  548.684066]  [<ffffffff803ad9e0>] ? neigh_timer_handler+0x0/0x2d0
> [  548.684066]  [<ffffffff8023521b>] ? run_timer_softirq+0x151/0x1bf
> [  548.684066]  [<ffffffff80231f40>] ? __do_softirq+0x65/0xcf
> [  548.684066]  [<ffffffff8020c20c>] ? call_softirq+0x1c/0x28
> [  548.684066]  [<ffffffff8020d8b4>] ? do_softirq+0x2c/0x68
> [  548.684066]  [<ffffffff8021919d>] ? smp_apic_timer_interrupt+0x8a/0xa5
> [  548.684066]  [<ffffffff8020bcb6>] ? apic_timer_interrupt+0x66/0x70
> [  548.684066]  <EOI>  [<ffffffff880d549c>] ?
> :raid456:raid5_compute_sector+0x19
> [  548.684066]  [<ffffffff880d5511>] ? :raid456:stripe_to_pdidx+0x48/0x51
> [  548.684066]  [<ffffffff880db728>] ? :raid456:sync_request+0x7d3/0x8a1
> [  548.684066]  [<ffffffff802edf17>] ? generic_unplug_device+0x18/0x24
> [  548.684066]  [<ffffffff802ecdef>] ? blk_unplug+0x5a/0x60
> [  548.684066]  [<ffffffff880d51af>] ? :raid456:unplug_slaves+0x55/0x91
> [  548.684066]  [<ffffffff880b0884>] ? :md_mod:md_do_sync+0x54e/0x96c
> [  548.684066]  [<ffffffff802429a7>] ? getnstimeofday+0x2f/0x83
> [  548.684066]  [<ffffffff802263e0>] ? try_to_wake_up+0xfd/0x10e
> [  548.684066]  [<ffffffff880b2ff6>] ? :md_mod:md_thread+0xde/0xfa
> [  548.684066]  [<ffffffff880b2f18>] ? :md_mod:md_thread+0x0/0xfa
> [  548.684066]  [<ffffffff8023e741>] ? kthread+0x47/0x76
> [  548.684066]  [<ffffffff80228ebd>] ? schedule_tail+0x28/0x5c
> [  548.684066]  [<ffffffff8020be98>] ? child_rip+0xa/0x12
> [  548.684066]  [<ffffffff8023e6fa>] ? kthread+0x0/0x76
> [  548.684066]  [<ffffffff8020be8e>] ? child_rip+0x0/0x12
> [  548.684066]
> 
> and the machine continued hanging.
> 
> Downgraded to 2.6.23 again, seems to work fine. Will try 2.6.24.2 shortly.

This looks like a networking regression, not a RAID regression.

We did have a big locking bug in netlink in 2.6.25-rc2, although your trace
doesn't appear to point at that particular bug.

It would be good if you could test the latest Linux snapshot please, see if
we've already fixed this, thanks.

Re: [Bugme-new] [Bug 10061] New: Hang in md5_resync

[Steinar H. Gunderson]

On Thu, Feb 21, 2008 at 05:07:37PM -0800, Andrew Morton wrote:
> It would be good if you could test the latest Linux snapshot please, see if
> we've already fixed this, thanks.

This is slightly difficult; it's a production machine.

I _might_ be able to do it tomorrow, but no guarantees.

/* Steinar */
-- 
Homepage: http://www.sesse.net/

Re: [Bugme-new] [Bug 10061] New: Hang in md5_resync

[Steinar H. Gunderson]

On Thu, Feb 21, 2008 at 05:07:37PM -0800, Andrew Morton wrote:
>> Downgraded to 2.6.23 again, seems to work fine. Will try 2.6.24.2 shortly.
> This looks like a networking regression, not a RAID regression.
> 
> We did have a big locking bug in netlink in 2.6.25-rc2, although your trace
> doesn't appear to point at that particular bug.
> 
> It would be good if you could test the latest Linux snapshot please, see if
> we've already fixed this, thanks.

The latest git snapshot seems to fix it; at least it's up again now (after an
age-long fsck), with no crash yet (it crashed very early on with 2.6.25-rc2).

/* Steinar */
-- 
Homepage: http://www.sesse.net/