Commit d8354a1d authored by Halil Pasic's avatar Halil Pasic Committed by Vasily Gorbik
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s390/virtio_ccw: Fix config change notifications 



Commit e3e9bda3 ("s390/virtio_ccw: use DMA handle from DMA API")
broke configuration change notifications for virtio-ccw by putting the
DMA address of *indicatorp directly into ccw->cda disregarding the fact
that if !!(vcdev->is_thinint) then the function
virtio_ccw_register_adapter_ind() will overwrite that ccw->cda value
with the address of the virtio_thinint_area so it can actually set up
the adapter interrupts via CCW_CMD_SET_IND_ADAPTER.  Thus we end up
pointing to the wrong object for both CCW_CMD_SET_IND if setting up the
adapter interrupts fails, and for CCW_CMD_SET_CONF_IND regardless
whether it succeeds or fails.

To fix this, let us save away the dma address of *indicatorp in a local
variable, and copy it to ccw->cda after the "vcdev->is_thinint" branch.

Fixes: e3e9bda3 ("s390/virtio_ccw: use DMA handle from DMA API")
Reported-by: default avatarBoqiao Fu <bfu@redhat.com>
Reported-by: default avatarSebastian Mitterle <smitterl@redhat.com>
Closes: https://issues.redhat.com/browse/RHEL-39983


Tested-by: default avatarThomas Huth <thuth@redhat.com>
Reviewed-by: default avatarEric Farman <farman@linux.ibm.com>
Signed-off-by: default avatarHalil Pasic <pasic@linux.ibm.com>
Link: https://lore.kernel.org/r/20240611214716.1002781-1-pasic@linux.ibm.com


Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 4181b51c

drivers/s390/virtio/virtio_ccw.c

+3 −1
Original line number Diff line number Diff line
@@ -698,6 +698,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs, 
	dma64_t *indicatorp = NULL;

	int ret, i, queue_idx = 0;

	struct ccw1 *ccw;

	dma32_t indicatorp_dma = 0;



	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);

	if (!ccw)
@@ -725,7 +726,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs, 
	*/

	indicatorp = ccw_device_dma_zalloc(vcdev->cdev,

					   sizeof(*indicatorp),

					   &ccw->cda);

					   &indicatorp_dma);

	if (!indicatorp)

		goto out;

	*indicatorp = indicators_dma(vcdev);
@@ -735,6 +736,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs, 
			/* no error, just fall back to legacy interrupts */

			vcdev->is_thinint = false;

	}

	ccw->cda = indicatorp_dma;

	if (!vcdev->is_thinint) {

		/* Register queue indicators with host. */

		*indicators(vcdev) = 0;