I have a power-hungry NVMe-to-USB-C enclosure that sometimes falls offline under heavy load and disconnects from the USB. Normally I curse and re-plug it into a powered hub and go on with things. But I'm running Linus' master (6.0-rc3 of Sunday August 28th, which also has the asynchronous resume support rework reverted) and I was seeing a lot of the below (along with a hanging up of the USB). Reverting f323896f (and setting it up to reproduce the disk error/disconnect) seems to have fixed the "usb_hub_wq hub_event" hangup, at least at first glance. -Kenny ---- Aug 30 11:26:36 xps-7390 kernel: [12225.445356][T20556] I/O error, dev sdb, sector 314643672 op 0x1:(WRITE) flags 0x800 phys_seg 1 prio class 2 Aug 30 11:26:36 xps-7390 kernel: [12225.445360][T20556] sd 1:0:0:0: [sdb] tag#9 FAILED Result: hostbyte=DID_TIME_OUT dr iverbyte=DRIVER_OK cmd_age=30s Aug 30 11:26:36 xps-7390 kernel: [12225.445361][T20556] sd 1:0:0:0: [sdb] tag#9 CDB: Write(10) 2a 00 12 c1 11 48 00 00 08 00 Aug 30 11:26:36 xps-7390 kernel: [12225.445362][T20556] I/O error, dev sdb, sector 314642760 op 0x1:(WRITE) flags 0x800 phys_seg 1 prio class 2 Aug 30 11:26:36 xps-7390 kernel: [12225.445412][ T72] sd 1:0:0:0: rejecting I/O to offline device Aug 30 11:27:37 xps-7390 systemd-udevd[465]: sdb1: Worker [20868] processing SEQNUM=5188 is taking a long time Aug 30 11:28:08 xps-7390 kernel: [12316.738013][T15511] usb 3-9: USB disconnect, device number 14 Aug 30 11:28:08 xps-7390 kernel: [12316.738020][T15511] usb 3-9.4: USB disconnect, device number 17 Aug 30 11:28:08 xps-7390 kernel: [12316.739071][T15511] usb 3-9.5: USB disconnect, device number 18 Aug 30 11:29:37 xps-7390 systemd-udevd[465]: sdb1: Worker [20868] processing SEQNUM=5188 killed Aug 30 11:29:37 xps-7390 systemd-udevd[465]: Worker [20868] terminated by signal 9 (KILL) Aug 30 11:29:37 xps-7390 systemd-udevd[465]: sdb1: Worker [20868] failed Aug 30 11:29:43 xps-7390 kernel: [12411.657995][ T55] INFO: task kworker/4:1:11393 blocked for more than 122 seconds. Aug 30 11:29:43 xps-7390 kernel: [12411.658007][ T55] Tainted: G S U O 6.0.0-rc3-XPS-Kenny+ #3 Aug 30 11:29:43 xps-7390 kernel: [12411.658011][ T55] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Aug 30 11:29:43 xps-7390 kernel: [12411.658013][ T55] task:kworker/4:1 state:D stack: 0 pid:11393 ppid: 2 flags:0x00004000 Aug 30 11:29:43 xps-7390 kernel: [12411.658020][ T55] Workqueue: usb_hub_wq hub_event Aug 30 11:29:43 xps-7390 kernel: [12411.658030][ T55] Call Trace: Aug 30 11:29:43 xps-7390 kernel: [12411.658033][ T55] <TASK> Aug 30 11:29:43 xps-7390 kernel: [12411.658035][ T55] __schedule+0x3fc/0x5e0 Aug 30 11:29:43 xps-7390 kernel: [12411.658042][ T55] schedule+0x4f/0x80 Aug 30 11:29:43 xps-7390 kernel: [12411.658047][ T55] scsi_remove_host+0x185/0x200 Aug 30 11:29:43 xps-7390 kernel: [12411.658053][ T55] ? wake_bit_function+0x50/0x50 Aug 30 11:29:43 xps-7390 kernel: [12411.658060][ T55] usb_stor_disconnect+0x64/0xb0 Aug 30 11:29:43 xps-7390 kernel: [12411.658066][ T55] usb_unbind_interface+0xb0/0x250 Aug 30 11:29:43 xps-7390 kernel: [12411.658071][ T55] device_release_driver_internal+0x1b4/0x2c0 Aug 30 11:29:43 xps-7390 kernel: [12411.658077][ T55] bus_remove_device+0xd3/0x100 Aug 30 11:29:43 xps-7390 kernel: [12411.658081][ T55] device_del+0x252/0x470 Aug 30 11:29:43 xps-7390 kernel: [12411.658085][ T55] usb_disable_device+0x6b/0x180 Aug 30 11:29:43 xps-7390 kernel: [12411.658089][ T55] usb_disconnect+0xf7/0x260 Aug 30 11:29:43 xps-7390 kernel: [12411.658094][ T55] usb_disconnect+0xe1/0x260 Aug 30 11:29:43 xps-7390 kernel: [12411.658107][ T55] hub_event+0xbe8/0x1860 Aug 30 11:29:43 xps-7390 kernel: [12411.658113][ T55] process_one_work+0x1e7/0x340 Aug 30 11:29:43 xps-7390 kernel: [12411.658118][ T55] worker_thread+0x24d/0x490 Aug 30 11:29:43 xps-7390 kernel: [12411.658123][ T55] ? process_one_work+0x340/0x340 Aug 30 11:29:43 xps-7390 kernel: [12411.658126][ T55] kthread+0xd4/0xe0 Aug 30 11:29:43 xps-7390 kernel: [12411.658130][ T55] ? kthread_unuse_mm+0x80/0x80 Aug 30 11:29:43 xps-7390 kernel: [12411.658133][ T55] ret_from_fork+0x1f/0x30 Aug 30 11:29:43 xps-7390 kernel: [12411.658138][ T55] </TASK> ---- -Kenny -- Kenneth R. Crudup / Sr. SW Engineer, Scott County Consulting, Orange County CA
