Comment 89 for bug 561210

Having similar problem on:

Linux chris-laptop 3.0.0-19-generic #32-Ubuntu SMP Thu Apr 5 18:22:38 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux.

The wired Ethernet interface seems to fail until the system is rebooted. (The slower wireless interface - which is running in parallel to the same switch - was not affected.)

The system log shows the following:

Apr 19 18:17:31 chris-laptop kernel: [ 2400.492131] INFO: task python:4151 blocked for more than 120 seconds.
Apr 19 18:17:31 chris-laptop kernel: [ 2400.492135] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Apr 19 18:17:31 chris-laptop kernel: [ 2400.492138] python D ffffffff81805120 0 4151 4150 0x00000000
Apr 19 18:17:31 chris-laptop kernel: [ 2400.492142] ffff880134cf1bb8 0000000000000046 ffff880134cf1b58 ffffffff81032a79
Apr 19 18:17:31 chris-laptop kernel: [ 2400.492147] ffff880134cf1fd8 ffff880134cf1fd8 ffff880134cf1fd8 0000000000012a40
Apr 19 18:17:31 chris-laptop kernel: [ 2400.492150] ffff880138f10000 ffff880136660000 ffff880134cf1b98 ffff88013fd132c0
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492205] Call Trace:
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492213] [<ffffffff81032a79>] ? default_spin_lock_flags+0x9/0x10
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492218] [<ffffffff8110a320>] ? __lock_page+0x70/0x70
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492222] [<ffffffff815f22df>] schedule+0x3f/0x60
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492225] [<ffffffff815f238f>] io_schedule+0x8f/0xd0
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492227] [<ffffffff8110a32e>] sleep_on_page+0xe/0x20
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492230] [<ffffffff815f2baf>] __wait_on_bit+0x5f/0x90
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492233] [<ffffffff8110a498>] wait_on_page_bit+0x78/0x80
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492237] [<ffffffff81081de0>] ? autoremove_wake_function+0x40/0x40
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492240] [<ffffffff8110a5ac>] filemap_fdatawait_range+0x10c/0x1a0
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492243] [<ffffffff8110bfd8>] filemap_write_and_wait_range+0x68/0x80
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492247] [<ffffffff81194ac2>] vfs_fsync_range+0x42/0xa0
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492250] [<ffffffff81194b8c>] vfs_fsync+0x1c/0x20
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492272] [<ffffffffa06632e3>] nfs_file_flush+0x53/0x80 [nfs]
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492276] [<ffffffff811668df>] filp_close+0x3f/0x90
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492280] [<ffffffff81060faa>] put_files_struct.part.14+0x7a/0xe0
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492283] [<ffffffff81062aa8>] put_files_struct+0x18/0x20
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492286] [<ffffffff81062b74>] exit_files+0x54/0x70
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492289] [<ffffffff8106308d>] do_exit+0x19d/0x440
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492291] [<ffffffff810634d4>] do_group_exit+0x44/0xa0
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492294] [<ffffffff81063547>] sys_exit_group+0x17/0x20
Apr 19 18:21:31 chris-laptop kernel: [ 2640.492297] [<ffffffff815fc642>] system_call_fastpath+0x16/0x1b

I ran a Wireshark trace on the Ethernet interface shortly after it went down. This showed DHCP packets apparently being sent out, with nothing being received back.