https://bugzilla.kernel.org/show_bug.cgi?id=220491 --- Comment #54 from Mathias Nyman (mathias.nyman@xxxxxxxxxxxxxxx) --- I'm not sure if the kdb stall is helpful, or if it just adds one more moving part to this whole issue, possibly even causing usb link issues. The USB SD device, and xHCI controller are probably still running, expecting cpu/device drivers to handle certain things in time. Anyways, your dmesg does reveal another issue in recovering links in ss.inactive error state. port_event() in hub.c ends up resetting just the port, even if a usb device is present and the whole device should be reset. After a successful reset port_event() calls hub_port_connect_change(..., portstatus, portchange) with old, stale, pre-reset portstatus value. Details: Link goes to ss.Inactive error state "0x2c0", this is common on disconnect before link goes to rx.detect. Driver gives it some time before reset: [62691.183508] xhci_hcd .&checktime(0000,00,14,':').0: Transfer error for slot 6 ep 3 on endpoint [62691.204674] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2c0, return 0x2c0 [62691.204720] usb usb3-port4: Wait for inactive link disconnect detect [62691.228672] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2c0, return 0x2c0 [62691.228722] usb usb3-port4: Wait for inactive link disconnect detect [62691.252648] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2c0, return 0x2c0 [62691.252692] usb usb3-port4: Wait for inactive link disconnect detect [62691.276646] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2c0, return 0x2c0 [62691.276695] usb usb3-port4: Wait for inactive link disconnect detect [62691.300652] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2c0, return 0x2c0 [62691.300697] usb usb3-port4: Wait for inactive link disconnect detect Here we only reset the port when we should reset the whole device. Looks like this is because USB3 portstatus doesn't show "connected" when link is in ss.Inactive error, and the following check in hub.c port_event() is true: else if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION) || udev->state == USB_STATE_NOTATTACHED) { [62691.300704] usb usb3-port4: do warm reset, port only [62691.316596] xhci_hcd .&checktime(0000,00,14,':').0: xhci_hub_status_data: stopping usb3 port polling [62691.356676] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2d0, return 0x2d0 [62691.356722] usb usb3-port4: not warm reset yet, waiting 50ms [62691.408710] xhci_hcd .&checktime(0000,00,14,':').0: Port change event, 3-4, id 15, portsc: 0x2a1203 [62691.408729] xhci_hcd .&checktime(0000,00,14,':').0: handle_port_status: starting usb3 port polling. [62691.412657] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x2a1203, return 0x310203 [62691.412787] usb usb3-port4: Connection change during reset, retrying [62691.412812] xhci_hcd .&checktime(0000,00,14,':').0: clear port4 connect change, portsc: 0x281203 [62691.412832] hub 3-0:1.0: port_wait_reset: err = -11 [62691.412837] usb usb3-port4: not enabled, trying warm reset again... [62691.616651] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x281203, return 0x300203 [62691.616709] xhci_hcd .&checktime(0000,00,14,':').0: clear port4 reset change, portsc: 0x81203 [62691.616732] xhci_hcd .&checktime(0000,00,14,':').0: clear port4 warm(BH) reset change, portsc: 0x1203 [62691.616752] xhci_hcd .&checktime(0000,00,14,':').0: clear port4 link state change, portsc: 0x1203 [62691.616768] xhci_hcd .&checktime(0000,00,14,':').0: Get port status 3-4 read: 0x1203, return 0x203 port is now properly reset and ready in enabled u0 "0x1203" state. hub driver does however call hub_port_connect_change() with stale portstatus value still showing link in ss.Inactive "0x2c0": [62691.672631] usb usb3-port4: status 02c0, change 0041, 5.0 Gb/s [62741.591943] xhci_hcd .&checktime(0000,00,14,':').0: xhci_hub_status_data: stopping usb3 port polling [62741.593180] usb 3-4: USB disconnect, device number 3 -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.