Commit ed194d13 authored Sep 10, 2018 by Sebastian Andrzej Siewior Committed by Greg Kroah-Hartman Sep 10, 2018

usb: core: remove local_irq_save() around ->complete() handler



The core disabled interrupts before invocation the ->complete handler
because the handler might have expected that interrupts are disabled.

All handlers were audited and use proper locking now. With it, the core
code no longer needs to disable interrupts before invoking the
->complete handler.
Remove local_irq_save() statement before invoking the ->complete
handler.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 3f3ff6e0

drivers/usb/core/hcd.c

+0 −13

Original line number	Diff line number	Diff line
		@@ -1755,20 +1755,7 @@ static void __usb_hcd_giveback_urb(struct urb *urb)

		/* pass ownership to the completion handler */
		urb->status = status;

		/*
		* We disable local IRQs here avoid possible deadlock because
		* drivers may call spin_lock() to hold lock which might be
		* acquired in one hard interrupt handler.
		*
		* The local_irq_save()/local_irq_restore() around complete()
		* will be removed if current USB drivers have been cleaned up
		* and no one may trigger the above deadlock situation when
		* running complete() in tasklet.
		*/
		local_irq_save(flags);
		urb->complete(urb);
		local_irq_restore(flags);

		usb_anchor_resume_wakeups(anchor);
		atomic_dec(&urb->use_count);