Commit bf3f8378 authored by Ursula Braun's avatar Ursula Braun Committed by Martin Schwidefsky
Browse files

[S390] qdio: avoid hang when establishing qdio queues 



If qdio establish runs in parallel with a channel error,
ccw_device_start_timeout may not trigger the qdio_timeout_handler.
In this case neither QDIO_IRQ_STATE_ESTABLISHED nor
QDIO_IRQ_STATE_ERR is reached and the following wait_event hangs
forever.
Solution: do not make use of the timeout option with
ccw_device_start, but add a timeout to the following wait_event.

Signed-off-by: default avatarUrsula Braun <braunu@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 522d8dc0

drivers/s390/cio/qdio.c

+8 −10
Original line number Diff line number Diff line
@@ -3189,13 +3189,11 @@ qdio_establish(struct qdio_initialize *init_data) 
	spin_lock_irqsave(get_ccwdev_lock(cdev),saveflags);



	ccw_device_set_options_mask(cdev, 0);

	result=ccw_device_start_timeout(cdev,&irq_ptr->ccw,

					QDIO_DOING_ESTABLISH,0, 0,

					QDIO_ESTABLISH_TIMEOUT);

	result = ccw_device_start(cdev, &irq_ptr->ccw,

				QDIO_DOING_ESTABLISH, 0, 0);

	if (result) {

		result2=ccw_device_start_timeout(cdev,&irq_ptr->ccw,

						 QDIO_DOING_ESTABLISH,0,0,

						 QDIO_ESTABLISH_TIMEOUT);

		result2 = ccw_device_start(cdev, &irq_ptr->ccw,

					QDIO_DOING_ESTABLISH, 0, 0);

		sprintf(dbf_text,"eq:io%4x",result);

		QDIO_DBF_TEXT2(1,setup,dbf_text);

		if (result2) {
@@ -3219,10 +3217,10 @@ qdio_establish(struct qdio_initialize *init_data) 
		return result;

	}

	

	/* Timeout is cared for already by using ccw_device_start_timeout(). */

	wait_event_interruptible(cdev->private->wait_q,

	wait_event_interruptible_timeout(cdev->private->wait_q,

		irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||

		 irq_ptr->state == QDIO_IRQ_STATE_ERR);

		irq_ptr->state == QDIO_IRQ_STATE_ERR,

		QDIO_ESTABLISH_TIMEOUT);



	if (irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED)

		result = 0;

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