libertas USB: don't set surpriseremoved flag
We found a deadlock in the handling of command failures/reset conditions. For example: 1. Two commands are in the queue. 2. The first command is sent, but causes a timeout, which kicks off an asynchronous device reset 3. The second command is queued (but not yet sent to the hardware) 4. The device reset kicks in, causing the if_usb disconnect handler to set the "surprise removed" flag to be set as the device disappears from the bus. This causes lbs_thread to stop processing things ("adapter removed; waiting to die"), not processing any further commands, leaving the second queued command "in the air", causing a deadlock. Fix this by removing the surpriseremoved flag setting in if_usb. I can't see any reason why this needs to be done so early. lbs_remove_card will set this flag at an appropriate time - i.e. after all pending commands have been completed or cancelled, avoiding this deadlock. Signed-off-by: Daniel Drake <dsd@laptop.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
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@ -309,7 +309,6 @@ static void if_usb_disconnect(struct usb_interface *intf)
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cardp->surprise_removed = 1;
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if (priv) {
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priv->surpriseremoved = 1;
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lbs_stop_card(priv);
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lbs_remove_card(priv);
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}
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