4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aaron Ma <aaron.ma@xxxxxxxxxxxxx> commit 958c0bd86075d4ef1c936998deefe1947e539240 upstream. Realtek USB3.0 Card Reader [0bda:0328] reports wrong port status on Cannon lake PCH USB3.1 xHCI [8086:a36d] after resume from S3, after clear port reset it works fine. Since this device is registered on USB3 roothub at boot, when port status reports not superspeed, xhci_get_port_status will call an uninitialized completion in bus_state[0]. Kernel will hang because of NULL pointer. Restrict the USB2 resume status check in USB2 roothub to fix hang issue. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Aaron Ma <aaron.ma@xxxxxxxxxxxxx> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/host/xhci-hub.c | 2 +- drivers/usb/host/xhci-ring.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -876,7 +876,7 @@ static u32 xhci_get_port_status(struct u status |= USB_PORT_STAT_SUSPEND; } if ((raw_port_status & PORT_PLS_MASK) == XDEV_RESUME && - !DEV_SUPERSPEED_ANY(raw_port_status)) { + !DEV_SUPERSPEED_ANY(raw_port_status) && hcd->speed < HCD_USB3) { if ((raw_port_status & PORT_RESET) || !(raw_port_status & PORT_PE)) return 0xffffffff; --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1642,7 +1642,7 @@ static void handle_port_status(struct xh * RExit to a disconnect state). If so, let the the driver know it's * out of the RExit state. */ - if (!DEV_SUPERSPEED_ANY(portsc) && + if (!DEV_SUPERSPEED_ANY(portsc) && hcd->speed < HCD_USB3 && test_and_clear_bit(hcd_portnum, &bus_state->rexit_ports)) { complete(&bus_state->rexit_done[hcd_portnum]);