3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> [This is upstream commit 2d4fa940f99663c82ba55b2244638833b388e4e2. It needs to be backported to kernels as old as 3.2, because it fixes the buggy commit 65bdac5effd15d6af619b3b7218627ef4d84ed6a "USB: Handle warm reset failure on empty port."] The next patch will refactor the hub port code to rip out the recursive call to hub_port_reset on a failed hot reset. In preparation for that, make sure all code paths can deal with being called with a NULL udev. The usb_device will not be valid if warm reset was issued because a port transitioned to the Inactive or Compliance Mode on a device connect. This patch should have no effect on current behavior. Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/core/hub.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2584,6 +2584,9 @@ static int hub_port_wait_reset(struct us return -ENOTCONN; if ((portstatus & USB_PORT_STAT_ENABLE)) { + if (!udev) + return 0; + if (hub_is_wusb(hub)) udev->speed = USB_SPEED_WIRELESS; else if (hub_is_superspeed(hub->hdev)) @@ -2627,13 +2630,15 @@ static void hub_port_finish_reset(struct struct usb_hcd *hcd; /* TRSTRCY = 10 ms; plus some extra */ msleep(10 + 40); - update_devnum(udev, 0); - hcd = bus_to_hcd(udev->bus); - /* The xHC may think the device is already reset, - * so ignore the status. - */ - if (hcd->driver->reset_device) - hcd->driver->reset_device(hcd, udev); + if (udev) { + update_devnum(udev, 0); + hcd = bus_to_hcd(udev->bus); + /* The xHC may think the device is already + * reset, so ignore the status. + */ + if (hcd->driver->reset_device) + hcd->driver->reset_device(hcd, udev); + } } /* FALL THROUGH */ case -ENOTCONN: @@ -2647,7 +2652,7 @@ static void hub_port_finish_reset(struct clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_PORT_LINK_STATE); } - if (!warm) + if (!warm && udev) usb_set_device_state(udev, *status ? USB_STATE_NOTATTACHED : USB_STATE_DEFAULT); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html