Alan Stern pointed out that a USB port could potentially get powered off when the attached USB device is in the middle of enumerating, due to race conditions: http://marc.info/?l=linux-usb&m=134130616707548&w=2 If that happens, we need to ensure the enumeration fails. If a call to usb_get_descriptor() fails for a reason other than a Stall, return an error. That should handle the case where the port is powered off. Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Lan Tianyu <tianyu.lan@xxxxxxxxx> Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> --- drivers/usb/core/config.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c index f4bdd0c..7199adc 100644 --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -702,6 +702,8 @@ int usb_get_configuration(struct usb_device *dev) if (result < 0) { dev_err(ddev, "unable to read config index %d " "descriptor/%s: %d\n", cfgno, "start", result); + if (result != -EPIPE) + goto err; dev_err(ddev, "chopping to %d config(s)\n", cfgno); dev->descriptor.bNumConfigurations = cfgno; break; -- 1.7.9.5 -- 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
