Hi Dave, what made me file my logs here is that both the symptom (lsusb hanging) and what looks like the underlying cause are both the same. A crash of khubd kernel thread is always there, with a similar stack trace in every case, triggered by the same pattern: usb_stor_disconnect -> usb_stor_disconnect -> kthread_stop -> ...
E.g. this is from a post above: [ 1680.200076] khubd D 000164da 0 22 2 0x00000000 [ 1680.200086] f710bd34 00000046 e68a0000 000164da 00000000 c0848760 f7100f64 c0848760 [ 1680.200099] 7478828a 0000011c c0848760 c0848760 f7100f64 c0848760 c0848760 f2616000 [ 1680.200110] 00000000 0000011c f7100cc0 7fffffff 7fffffff e68a1fc8 f710bd94 c058c1ed [ 1680.200121] Call Trace: [ 1680.200138] [<c058c1ed>] schedule_timeout+0x1ad/0x280 [ 1680.200148] [<c014926b>] ? check_preempt_wakeup+0x20b/0x370 [ 1680.200157] [<c0132c0e>] ? enqueue_task+0x7e/0xa0 [ 1680.200165] [<c058bea6>] wait_for_common+0xa6/0x130 [ 1680.200174] [<c014248f>] ? try_to_wake_up+0x2ef/0x4a0 [ 1680.200182] [<c0142640>] ? default_wake_function+0x0/0x20 [ 1680.200200] [<c058bfe7>] wait_for_completion+0x17/0x20 [ 1680.200208] [<c016790f>] kthread_stop+0x3f/0xa0 [ 1680.200223] [<f809cf68>] release_everything+0x28/0xb0 [usb_storage] [ 1680.200236] [<f809d00f>] usb_stor_disconnect+0x1f/0x30 [usb_storage] [ 1680.200244] [<c044bd06>] usb_unbind_interface+0x46/0x130 [ 1680.200254] [<c03e7fa1>] __device_release_driver+0x51/0xb0 [ 1680.200260] [<c03e80c5>] device_release_driver+0x25/0x40 [ 1680.200269] [<c03e737b>] bus_remove_device+0x7b/0xa0 [ 1680.200277] [<c03e57f7>] device_del+0xf7/0x180 [ 1680.200283] [<c0448b13>] usb_disable_device+0x63/0x110 [ 1680.200292] [<c04435fe>] usb_disconnect+0x9e/0x120 [ 1680.200300] [<c0443b5b>] hub_port_connect_change+0x8b/0x890 [ 1680.200307] [<c0449785>] ? usb_control_msg+0xd5/0x130 [ 1680.200315] [<c0441590>] ? clear_port_feature+0x50/0x60 [ 1680.200323] [<c0444b05>] hub_events+0x1f5/0x510 [ 1680.200330] [<c0167cbf>] ? finish_wait+0x4f/0x70 [ 1680.200337] [<c0444e5a>] hub_thread+0x3a/0x140 [ 1680.200344] [<c0167b50>] ? autoremove_wake_function+0x0/0x50 [ 1680.200352] [<c0444e20>] ? hub_thread+0x0/0x140 [ 1680.200358] [<c01678c4>] kthread+0x74/0x80 [ 1680.200365] [<c0167850>] ? kthread+0x0/0x80 [ 1680.200373] [<c0104087>] kernel_thread_helper+0x7/0x10 while this is mine: [42722.411019] Call Trace: [42722.411030] [<ffffffff815c85dd>] schedule_timeout+0x26d/0x2e0 [42722.411038] [<ffffffff810576a3>] ? update_curr+0x103/0x210 [42722.411044] [<ffffffff815c8099>] wait_for_common+0xd9/0x180 [42722.411049] [<ffffffff8105f690>] ? default_wake_function+0x0/0x20 [42722.411056] [<ffffffff815c821d>] wait_for_completion+0x1d/0x20 [42722.411061] [<ffffffff810879e2>] kthread_stop+0x42/0xf0 [42722.411068] [<ffffffffa02375fe>] release_everything+0x2e/0xb0 [usb_storage] [42722.411074] [<ffffffffa02384ca>] usb_stor_disconnect+0x2a/0x40 [usb_storage] [42722.411081] [<ffffffff8144464a>] usb_unbind_interface+0x5a/0x1a0 [42722.411089] [<ffffffff813bb305>] __device_release_driver+0x75/0xe0 [42722.411093] [<ffffffff813bb39d>] device_release_driver+0x2d/0x40 [42722.411097] [<ffffffff813bae4b>] bus_remove_device+0x7b/0xa0 [42722.411102] [<ffffffff813b80e7>] device_del+0x127/0x1b0 [42722.411106] [<ffffffff81442404>] usb_disable_device+0x74/0x130 [42722.411112] [<ffffffff8143b4e5>] usb_disconnect+0x95/0x130 [42722.411116] [<ffffffff81440aa8>] ? usb_init_urb+0x28/0x40 [42722.411120] [<ffffffff8143c29d>] hub_port_connect_change+0x9d/0x930 [42722.411125] [<ffffffff8143ce72>] hub_events+0x342/0x4e0 [42722.411130] [<ffffffff8143d045>] hub_thread+0x35/0x180 [42722.411134] [<ffffffff810880e0>] ? autoremove_wake_function+0x0/0x40 [42722.411138] [<ffffffff8143d010>] ? hub_thread+0x0/0x180 [42722.411141] [<ffffffff81087996>] kthread+0x96/0xa0 [42722.411147] [<ffffffff8100ce24>] kernel_thread_helper+0x4/0x10 [42722.411152] [<ffffffff81087900>] ? kthread+0x0/0xa0 [42722.411155] [<ffffffff8100ce20>] ? kernel_thread_helper+0x0/0x10 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/570049 Title: lsusb hangs forever To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/usbutils/+bug/570049/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
