Re: INFO: umount blocked for more than 120 seconds

From: Robert Hancock
Date: Mon Apr 26 2010 - 21:12:50 EST


On 04/26/2010 03:01 AM, Sergey Senozhatsky wrote:
Hello,
MiniSD card mounted through the USB card reader.

.34-rc5-git6

kernel: [ 5746.170226] scsi12 : usb-storage 2-2:1.0
kernel: [ 5747.174113] scsi scan: INQUIRY result too short (5), using 36
kernel: [ 5747.174128] scsi 12:0:0:0: Direct-Access PQ: 0 ANSI: 0
kernel: [ 5747.180721] sd 12:0:0:0: Attached scsi generic sg2 type 0
kernel: [ 5747.190490] sd 12:0:0:0: [sdb] 2012160 512-byte logical blocks: (1.03 GB/982 MiB)
kernel: [ 5747.193398] sd 12:0:0:0: [sdb] Write Protect is off
kernel: [ 5747.193403] sd 12:0:0:0: [sdb] Mode Sense: 00 06 00 00
kernel: [ 5747.193406] sd 12:0:0:0: [sdb] Assuming drive cache: write through
kernel: [ 5747.207116] sd 12:0:0:0: [sdb] Assuming drive cache: write through
kernel: [ 5747.207125] sdb: sdb1
kernel: [ 5747.233099] sd 12:0:0:0: [sdb] Assuming drive cache: write through
kernel: [ 5747.233112] sd 12:0:0:0: [sdb] Attached SCSI removable disk
kernel: [ 5758.495211] FAT: utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive!
kernel: [ 6360.626229] INFO: task umount:4235 blocked for more than 120 seconds.
kernel: [ 6360.626237] "echo 0> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: [ 6360.626246] umount D 0000059e 0 4235 3382 0x00000000
kernel: [ 6360.626259] f6e09e38 00000046 38aa246b 0000059e c1610cc0 c12c3880 c1610cc0 c1610cc0
kernel: [ 6360.626282] c1610cc0 c1610cc0 f6fa6cd0 c1610cc0 00002d16 00000000 38a9f755 0000059e
kernel: [ 6360.626304] f6fa6a40 f6e09e40 f6e09e70 00000000 f6e09e78 f6e09e40 c10b7cf0 f6e09e5c
kernel: [ 6360.626334] Call Trace:
kernel: [ 6360.626345] [<c12c3880>] ? _raw_spin_unlock_irqrestore+0x36/0x5b
kernel: [ 6360.626353] [<c10b7cf0>] bdi_sched_wait+0x8/0xc
kernel: [ 6360.626358] [<c12c20df>] __wait_on_bit+0x34/0x5b
kernel: [ 6360.626363] [<c10b7ce8>] ? bdi_sched_wait+0x0/0xc
kernel: [ 6360.626368] [<c12c215d>] out_of_line_wait_on_bit+0x57/0x5f
kernel: [ 6360.626373] [<c10b7ce8>] ? bdi_sched_wait+0x0/0xc
kernel: [ 6360.626379] [<c103fa75>] ? wake_bit_function+0x0/0x4d
kernel: [ 6360.626385] [<c10b84d4>] wait_on_bit.clone.0+0x17/0x23
kernel: [ 6360.626390] [<c10b8544>] sync_inodes_sb+0x64/0x10d
kernel: [ 6360.626397] [<c10d373f>] ? vfs_quota_sync+0x0/0x1da
kernel: [ 6360.626402] [<c10baef6>] __sync_filesystem+0x37/0x62
kernel: [ 6360.626407] [<c10bb062>] sync_filesystem+0x3c/0x3f
kernel: [ 6360.626413] [<c10a2def>] generic_shutdown_super+0x1c/0xca
kernel: [ 6360.626418] [<c10a2eba>] kill_block_super+0x1d/0x31
kernel: [ 6360.626423] [<c10a3833>] deactivate_super+0x48/0x5a
kernel: [ 6360.626429] [<c10b385c>] mntput_no_expire+0x5e/0x89
kernel: [ 6360.626434] [<c10b41cf>] sys_umount+0x277/0x29b
kernel: [ 6360.626440] [<c10b4200>] sys_oldumount+0xd/0xf
kernel: [ 6360.626445] [<c1002813>] sysenter_do_call+0x12/0x32
kernel: [ 6360.626450] 1 lock held by umount/4235:
kernel: [ 6360.626453] #0: (&type->s_umount_key#34){++++..}, at: [<c10a382e>] deactivate_super+0x43/0x5a

Is this some super-slow SD card or USB reader that you just wrote a bunch of data to? It's not impossible it could take 2 minutes for the writeout of all the dirty data to complete on unmount.. did the unmount ever complete?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/