On Sun, Jan 13, 2013 at 5:56 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Sun, 13 Jan 2013, Alex Riesen wrote: >> >> Yes, almost. What about khubd hanging when machine is shutdown? > > What about it? I have trouble understanding all the descriptions you > have provided so far, because you talk about several different things > and change your mind a lot. Can you provide a single, simple scenario > that illustrates this problem? 1. Compile a kernel with deadline elevator as module 2. Boot into it, make sure the elevator is selected (I used "elevator=deadline" in the kernel command line) 3. Insert a FAT formatted mass storage device in an USB2 port Observe "io scheduler deadline registered" 4. Pull the stick out, wait a moment, and either shutdown or just and press alt-sysrq-W: [ 158.170585] usb 1-1.2: USB disconnect, device number 3 [ 158.170590] usb 1-1.2: unregistering device [ 158.170595] usb 1-1.2: unregistering interface 1-1.2:1.0 [ 166.959398] SysRq : Show Blocked State [ 166.959410] task PC stack pid father [ 166.959432] khubd D ffff880213a68000 0 513 2 0x00000000 [ 166.959440] ffff880213affa18 0000000000000046 ffff88020000006b 0000000000000 [ 166.959448] ffff880213a68000 ffff880213afffd8 ffff880213afffd8 0000000000013 [ 166.959454] ffffffff81a14400 ffff880213a68000 ffff880213aff9a8 0000000000000 [ 166.959461] Call Trace: [ 166.959475] [<ffffffff8104d763>] ? flush_work+0x6d/0x1fe [ 166.959485] [<ffffffff8133defb>] ? scsi_remove_host+0x24/0x10e [ 166.959490] [<ffffffff8104d6fb>] ? flush_work+0x5/0x1fe [ 166.959499] [<ffffffff815e1dd6>] schedule+0x65/0x67 [ 166.959506] [<ffffffff815e201e>] schedule_preempt_disabled+0x18/0x24 [ 166.959513] [<ffffffff815e07e4>] mutex_lock_nested+0x181/0x2c1 [ 166.959518] [<ffffffff8133defb>] ? scsi_remove_host+0x24/0x10e [ 166.959524] [<ffffffff8133defb>] scsi_remove_host+0x24/0x10e [ 166.959531] [<ffffffff813910d5>] usb_stor_disconnect+0x77/0xbc [ 166.959539] [<ffffffff81377ca3>] usb_unbind_interface+0x6c/0x14d [ 166.959548] [<ffffffff813266fc>] __device_release_driver+0x88/0xdb [ 166.959554] [<ffffffff81326774>] device_release_driver+0x25/0x32 [ 166.959561] [<ffffffff8132616f>] bus_remove_device+0xf5/0x10a [ 166.959567] [<ffffffff8132413f>] device_del+0x12e/0x189 [ 166.959574] [<ffffffff81375d3a>] usb_disable_device+0xb1/0x20e [ 166.959582] [<ffffffff8136ed8b>] usb_disconnect+0xab/0x113 [ 166.959589] [<ffffffff81370218>] hub_port_connect_change+0x1b0/0x879 [ 166.959597] [<ffffffff81370e3a>] hub_events+0x559/0x69d [ 166.959604] [<ffffffff81370fb6>] hub_thread+0x38/0x19b [ 166.959612] [<ffffffff81052587>] ? wake_up_bit+0x2a/0x2a [ 166.959618] [<ffffffff81370f7e>] ? hub_events+0x69d/0x69d [ 166.959625] [<ffffffff81051f2a>] kthread+0xd5/0xdd [ 166.959632] [<ffffffff8105d5f6>] ? finish_task_switch+0x3f/0xf7 [ 166.959641] [<ffffffff81051e55>] ? __init_kthread_worker+0x5a/0x5a [ 166.959648] [<ffffffff815e965c>] ret_from_fork+0x7c/0xb0 [ 166.959655] [<ffffffff81051e55>] ? __init_kthread_worker+0x5a/0x5a This trace if from alt-sysrq-W. I can attach an image from the shutdown case, the traces from that case are hard to save: the main storage is usually already stopped. I believe it was the same, though. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
