Comment 37 for bug 276476

This started happening to me on 8.10 (2.6.27-16-generic) when I started a
real-disk-to-real-disk "cp -a" inside a guest 9.10 running inside VMware.
The host 8.10 is having a very hard time with this.

Yesterday, the time-outs were all firefox:

# grep 'blocked for more than 120 seconds' syslog.0 | tr : ' ' | acol 11 | sort | uniq -c
     48 firefox

Today, it's a mix:

      5 boinc
      3 fetchmail
      1 hal-acl-tool
      6 kjournald
      5 local
      1 mutt_dotlock
      1 pam-foreground-
      1 polkit-ian
      5 procmail
      6 rsync
      1 sadc
      5 setiathome_6.03
      1 sleep
      1 vmnet-dhcpd

Sample:

[68185.828301] INFO: task rsync:21998 blocked for more than 120 seconds.
[68185.828303] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[68185.828306] rsync D 0000ffff 0 21998 21980
[68185.828309] c0cd1cc8 00000086 ffffffff 0000ffff c9642840 c0cd1c90 00000008 c0cd1c80
[68185.828315] 00000246 c01d8285 c2c2cb60 00071b6d 00000000 f6e319cc 00000000 00000000
[68185.828321] c0514080 f70de000 c0cd0000 c2c2cdd8 c2b17d00 00000000 c02405b9 c2b17d00
[68185.828327] Call Trace:
[68185.828328] [<c01d8285>] ? alloc_buffer_head+0x15/0x40
[68185.828333] [<c02405b9>] ? generic_unplug_device+0x9/0x40
[68185.828338] [<c037febc>] io_schedule+0x2c/0x40
[68185.828341] [<c01d8a7d>] sync_buffer+0x3d/0x50
[68185.828344] [<c038049f>] __wait_on_bit+0x4f/0x70
[68185.828348] [<c01d8a40>] ? sync_buffer+0x0/0x50
[68185.828351] [<c038056d>] out_of_line_wait_on_bit+0xad/0xc0
[68185.828355] [<c01d8a40>] ? sync_buffer+0x0/0x50
[68185.828358] [<c0148700>] ? wake_bit_function+0x0/0x60
[68185.828362] [<c01d8bae>] __wait_on_buffer+0x2e/0x30
[68185.828366] [<f8a75f33>] wait_on_buffer+0x23/0x30 [ext3]
[68185.828383] [<f8a767c6>] __ext3_get_inode_loc+0x256/0x300 [ext3]
[68185.828392] [<c01c8a5b>] ? find_inode_fast+0xb/0x70
[68185.828396] [<c01c9197>] ? get_new_inode_fast+0xe7/0x120
[68185.828399] [<c01c9d1b>] ? iget_locked+0x5b/0x60
[68185.828404] [<f8a768cd>] ext3_iget+0x5d/0x3e0 [ext3]
[68185.828412] [<c01c5c7a>] ? d_rehash+0x4a/0x60
[68185.828417] [<c01c718e>] ? __d_lookup+0xe/0x120
[68185.828422] [<f8a7c169>] ext3_lookup+0x89/0xd0 [ext3]
[68185.828431] [<c03817ed>] ? _spin_lock+0xd/0x10
[68185.828435] [<c01c79bf>] ? d_alloc+0x13f/0x1a0
[68185.828444] [<c01bd1df>] real_lookup+0xaf/0x110
[68185.828447] [<c01bd2cd>] do_lookup+0x8d/0xd0
[68185.828451] [<c01bd84d>] __link_path_walk+0x53d/0xb40
[68185.828454] [<c01be2b4>] path_walk+0x54/0xb0
[68185.828457] [<c01be466>] do_path_lookup+0xb6/0x1a0
[68185.828461] [<c01bf07a>] user_path_at+0x4a/0x80
[68185.828464] [<c01b6f89>] ? cp_new_stat64+0xe9/0x100
[68185.828470] [<c01b74d3>] vfs_lstat_fd+0x23/0x50
[68185.828474] [<c01b7596>] vfs_lstat+0x16/0x20
[68185.828477] [<c01b75b9>] sys_lstat64+0x19/0x30
[68185.828481] [<c0104072>] syscall_call+0x7/0xb
[68185.828484] =======================