From: Richard Genoud Date: Thu, 3 Apr 2014 14:48:56 +0000 (+0200) Subject: rt2x00: Endless loop on hub port power down X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2ad69ac597619;p=linux-beck.git rt2x00: Endless loop on hub port power down I've met an endless (or at least very long) loop if I power down the usb port on witch a usb wifi key is plugged. (Ok, it's not very smart to power down a usb port when a usb key is in used... but still, I think that should not lead to an endless loop). I have a lot of: ieee80211 phy1: rt2x00usb_vendor_request: Error - Vendor Request 0x07 failed for offset 0x0438 with error -71 (-71==-EPROTO) How to reproduce: - plug an usb wifi key - ip link set wlan0 up - hub-ctrl -b usb_bus -d usb_device -P usb_port -p 0 hub-ctrl source: https://github.com/codazoda/hub-ctrl.c/blob/master/hub-ctrl.c The following patch prevents the endless loop, but I'm really not sure that The Right Way To Do It (R) Signed-off-by: Richard Genoud Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c index 10572452cc21..86c43d112a4b 100644 --- a/drivers/net/wireless/rt2x00/rt2x00usb.c +++ b/drivers/net/wireless/rt2x00/rt2x00usb.c @@ -68,6 +68,12 @@ int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev, } } + /* If the port is powered down, we get a -EPROTO error, and this + * leads to a endless loop. So just say that the device is gone. + */ + if (status == -EPROTO) + clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags); + rt2x00_err(rt2x00dev, "Vendor Request 0x%02x failed for offset 0x%04x with error %d\n", request, offset, status);