This is still happening in 10.04.1, both with the default Ubuntu server kernel and with the ppa kernel:

Linux topaz 2.6.35-22-server #33~lucid1-Ubuntu SMP Sat Sep 18 13:29:53 UTC 2010 x86_64 GNU/Linux


Oct  4 09:32:44 topaz kernel: [405000.890225] INFO: task scp:27169 blocked for more than 120 seconds.
Oct  4 09:32:44 topaz kernel: [405000.890231] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Oct  4 09:32:44 topaz kernel: [405000.890234] scp           D 000000010267dc02     0 27169  29503 0x00000004
Oct  4 09:32:44 topaz kernel: [405000.890241]  ffff88012f8b9c08 0000000000000086 ffff880200000000 0000000000015980
Oct  4 09:32:44 topaz kernel: [405000.890248]  ffff88012f8b9fd8 0000000000015980 ffff88012f8b9fd8 ffff88011cdb5b80
Oct  4 09:32:44 topaz kernel: [405000.890254]  0000000000015980 0000000000015980 ffff88012f8b9fd8 0000000000015980
Oct  4 09:32:44 topaz kernel: [405000.890259] Call Trace:
Oct  4 09:32:44 topaz kernel: [405000.890272]  [<ffffffff81100b60>] ? sync_page+0x0/0x50
Oct  4 09:32:44 topaz kernel: [405000.890279]  [<ffffffff8159ca93>] io_schedule+0x73/0xc0
Oct  4 09:32:44 topaz kernel: [405000.890283]  [<ffffffff81100b9d>] sync_page+0x3d/0x50
Oct  4 09:32:44 topaz kernel: [405000.890287]  [<ffffffff8159d10f>] __wait_on_bit+0x5f/0x90
Oct  4 09:32:44 topaz kernel: [405000.890292]  [<ffffffff81100d53>] wait_on_page_bit+0x73/0x80
Oct  4 09:32:44 topaz kernel: [405000.890297]  [<ffffffff8107f120>] ? wake_bit_function+0x0/0x40
Oct  4 09:32:44 topaz kernel: [405000.890303]  [<ffffffff8110b675>] ? pagevec_lookup_tag+0x25/0x40
Oct  4 09:32:44 topaz kernel: [405000.890307]  [<ffffffff8110121d>] filemap_fdatawait_range+0x10d/0x1a0
Oct  4 09:32:44 topaz kernel: [405000.890312]  [<ffffffff811012db>] filemap_fdatawait+0x2b/0x30
Oct  4 09:32:44 topaz kernel: [405000.890316]  [<ffffffff811015e4>] filemap_write_and_wait+0x44/0x50
Oct  4 09:32:44 topaz kernel: [405000.890334]  [<ffffffffa01abf3c>] nfs_setattr+0x14c/0x160 [nfs]
Oct  4 09:32:44 topaz kernel: [405000.890341]  [<ffffffff8116bebb>] notify_change+0x16b/0x310
Oct  4 09:32:44 topaz kernel: [405000.890347]  [<ffffffff8135cb9e>] ? tty_ldisc_deref+0xe/0x10
Oct  4 09:32:44 topaz kernel: [405000.890352]  [<ffffffff81152364>] do_truncate+0x64/0xa0
Oct  4 09:32:44 topaz kernel: [405000.890356]  [<ffffffff811525fb>] T.782+0xeb/0x110
Oct  4 09:32:44 topaz kernel: [405000.890360]  [<ffffffff8115262e>] sys_ftruncate+0xe/0x10
Oct  4 09:32:44 topaz kernel: [405000.890366]  [<ffffffff8100a0f2>] system_call_fastpath+0x16/0x1b
Oct  4 09:32:44 topaz kernel: [405000.890371] INFO: task flush-0:26:27661 blocked for more than 120 seconds.
Oct  4 09:32:44 topaz kernel: [405000.890373] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Oct  4 09:32:44 topaz kernel: [405000.890376] flush-0:26    D 0000000102694b5b     0 27661      2 0x00000000
Oct  4 09:32:44 topaz kernel: [405000.890383]  ffff8801324fda40 0000000000000046 0000000000000000 0000000000015980
Oct  4 09:32:44 topaz kernel: [405000.890388]  ffff8801324fdfd8 0000000000015980 ffff8801324fdfd8 ffff88015ab28000
Oct  4 09:32:44 topaz kernel: [405000.890394]  0000000000015980 0000000000015980 ffff8801324fdfd8 0000000000015980
Oct  4 09:32:44 topaz kernel: [405000.890399] Call Trace:
Oct  4 09:32:44 topaz kernel: [405000.890404]  [<ffffffff81100b60>] ? sync_page+0x0/0x50
Oct  4 09:32:44 topaz kernel: [405000.890410]  [<ffffffff8159ca93>] io_schedule+0x73/0xc0
Oct  4 09:32:44 topaz kernel: [405000.890415]  [<ffffffff81100b9d>] sync_page+0x3d/0x50
Oct  4 09:32:44 topaz kernel: [405000.890420]  [<ffffffff8159d10f>] __wait_on_bit+0x5f/0x90
Oct  4 09:32:44 topaz kernel: [405000.890423]  [<ffffffff81100d53>] wait_on_page_bit+0x73/0x80
Oct  4 09:32:44 topaz kernel: [405000.890428]  [<ffffffff8107f120>] ? wake_bit_function+0x0/0x40
Oct  4 09:32:44 topaz kernel: [405000.890432]  [<ffffffff8110b675>] ? pagevec_lookup_tag+0x25/0x40
Oct  4 09:32:44 topaz kernel: [405000.890436]  [<ffffffff8110121d>] filemap_fdatawait_range+0x10d/0x1a0
Oct  4 09:32:44 topaz kernel: [405000.890441]  [<ffffffff811012db>] filemap_fdatawait+0x2b/0x30
Oct  4 09:32:44 topaz kernel: [405000.890446]  [<ffffffff81175648>] writeback_single_inode+0x2e8/0x3f0
Oct  4 09:32:44 topaz kernel: [405000.890451]  [<ffffffff81175ba5>] writeback_sb_inodes+0x195/0x280
Oct  4 09:32:44 topaz kernel: [405000.890455]  [<ffffffff811765fc>] wb_writeback+0x12c/0x2b0
Oct  4 09:32:44 topaz kernel: [405000.890461]  [<ffffffff8106fefc>] ? lock_timer_base+0x3c/0x70
Oct  4 09:32:44 topaz kernel: [405000.890465]  [<ffffffff810709f2>] ? del_timer_sync+0x22/0x30
Oct  4 09:32:44 topaz kernel: [405000.890470]  [<ffffffff81176829>] wb_do_writeback+0xa9/0x190
Oct  4 09:32:44 topaz kernel: [405000.890474]  [<ffffffff81070010>] ? process_timeout+0x0/0x10
Oct  4 09:32:44 topaz kernel: [405000.890479]  [<ffffffff81176963>] bdi_writeback_task+0x53/0x160
Oct  4 09:32:44 topaz kernel: [405000.890483]  [<ffffffff8107efa7>] ? bit_waitqueue+0x17/0xd0
Oct  4 09:32:44 topaz kernel: [405000.890488]  [<ffffffff81119d76>] bdi_start_fn+0x86/0x100
Oct  4 09:32:44 topaz kernel: [405000.890492]  [<ffffffff81119cf0>] ? bdi_start_fn+0x0/0x100
Oct  4 09:32:44 topaz kernel: [405000.890496]  [<ffffffff8107eb86>] kthread+0x96/0xa0
Oct  4 09:32:44 topaz kernel: [405000.890501]  [<ffffffff8100aee4>] kernel_thread_helper+0x4/0x10
Oct  4 09:32:44 topaz kernel: [405000.890505]  [<ffffffff8107eaf0>] ? kthread+0x0/0xa0
Oct  4 09:32:44 topaz kernel: [405000.890508]  [<ffffffff8100aee0>] ? kernel_thread_helper+0x0/0x10