[reiserfs] system hangs due to blocked filesystem tasks

Every few days, a relatively disk-intensive task such as

find -type d -print0 | xargs -0 chmod u+s # or
cvs up

will cause my system to hang. The filesystem (reiser4 on /home) becomes blocked, with more and more processes piling up messages like:

Dec 2 10:20:22 helium kernel: [192960.871307] INFO: task reiserfs/1:1065 blocked for more than 120 seconds.
Dec 2 10:20:22 helium kernel: [192960.871316] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Dec 2 10:20:22 helium kernel: [192960.871322] reiserfs/1 D ffff880218496c30 0 1065 2 0x00000000
Dec 2 10:20:22 helium kernel: [192960.871333] ffff88022ceffd20 0000000000000046 0000000000000000 0000000000015980
Dec 2 10:20:22 helium kernel: [192960.871344] ffff88022cefffd8 0000000000015980 ffff88022cefffd8 ffff88021a7dadc0
Dec 2 10:20:22 helium kernel: [192960.871354] 0000000000015980 0000000000015980 ffff88022cefffd8 0000000000015980
Dec 2 10:20:22 helium kernel: [192960.871362] Call Trace:
Dec 2 10:20:22 helium kernel: [192960.871377] [<ffffffff81588617>] __mutex_lock_slowpath+0xf7/0x180
Dec 2 10:20:22 helium kernel: [192960.871387] [<ffffffff815884fb>] mutex_lock+0x2b/0x50
Dec 2 10:20:22 helium kernel: [192960.871420] [<ffffffffa0c84c55>] reiserfs_write_lock+0x35/0x50 [reiserfs]
Dec 2 10:20:22 helium kernel: [192960.871444] [<ffffffffa0c7ec49>] flush_async_commits+0x39/0x80 [reiserfs]
Dec 2 10:20:22 helium kernel: [192960.871466] [<ffffffffa0c7ec10>] ? flush_async_commits+0x0/0x80 [reiserfs]
Dec 2 10:20:22 helium kernel: [192960.871477] [<ffffffff8107a775>] run_workqueue+0xc5/0x1a0
Dec 2 10:20:22 helium kernel: [192960.871487] [<ffffffff8107a8f3>] worker_thread+0xa3/0x110
Dec 2 10:20:22 helium kernel: [192960.871496] [<ffffffff8107f620>] ? autoremove_wake_function+0x0/0x40
Dec 2 10:20:22 helium kernel: [192960.871505] [<ffffffff8107a850>] ? worker_thread+0x0/0x110
Dec 2 10:20:22 helium kernel: [192960.871512] [<ffffffff8107f0c6>] kthread+0x96/0xa0
Dec 2 10:20:22 helium kernel: [192960.871521] [<ffffffff8100aee4>] kernel_thread_helper+0x4/0x10
Dec 2 10:20:22 helium kernel: [192960.871529] [<ffffffff8107f030>] ? kthread+0x0/0xa0
Dec 2 10:20:22 helium kernel: [192960.871536] [<ffffffff8100aee0>] ? kernel_thread_helper+0x0/0x10

Once this happens the host becomes unresponsive to console input or ssh connections, although it does continue to pass network traffic, at least for a while. It eventually has to be force-rebooted.

This bug is similar to #494476. The effect of it is pretty severe, and I'd greatly appreciate a solution.

Thanks,
Andrew.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: linux-image-2.6.35-23-generic 2.6.35-23.41
Regression: Yes
Reproducible: No
ProcVersionSignature: Ubuntu 2.6.35-23.41-generic 2.6.35.7
Uname: Linux 2.6.35-23-generic x86_64
NonfreeKernelModules: nvidia
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Architecture: amd64
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: CS46xx [Sound Fusion CS46xx], device 0: CS46xx [CS46xx]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'CS46xx'/'Sound Fusion CS46xx at 0xfdaff000/0xfd900000, irq 20'
   Mixer name : 'Cirrus Logic CS4297A rev 4,Cirrus Logic CS4294 rev 5'
   Components : 'AC97a:43525914 AC97a:4352592d'
   Controls : 71
   Simple ctrls : 45
Date: Fri Dec 3 05:25:49 2010
Frequency: Once every few days.
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
MachineType: Gigabyte Technology Co., Ltd. GA-MA790XT-UD4P
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-23-generic root=UUID=9234eabd-576f-45d0-afee-62424eab19bc ro quiet splash nomodeset video=uvesafb:mode_option=1920x1200-24,mtrr=3,scroll=ywrap
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
RelatedPackageVersions: linux-firmware 1.38
RfKill:

SourcePackage: linux
WifiSyslog:
 Dec 3 03:26:37 helium dhclient: DHCPREQUEST of 192.168.1.2 on eth1 to 192.168.1.1 port 67
 Dec 3 03:26:37 helium dhclient: DHCPACK of 192.168.1.2 from 192.168.1.1
 Dec 3 03:26:37 helium dhclient: bound to 192.168.1.2 -- renewal in 31801 seconds.
 Dec 3 04:57:24 helium kernel: [44737.171753] EXT4-fs (sdb1): re-mounted. Opts: errors=remount-ro,acl,commit=0
 Dec 3 04:57:24 helium kernel: [44737.220796] EXT4-fs (dm-2): re-mounted. Opts: acl,commit=0
dmi.bios.date: 05/21/2009
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F4
dmi.board.name: GA-MA790XT-UD4P
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF4:bd05/21/2009:svnGigabyteTechnologyCo.,Ltd.:pnGA-MA790XT-UD4P:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-MA790XT-UD4P:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: GA-MA790XT-UD4P
dmi.sys.vendor: Gigabyte Technology Co., Ltd.