Commit e3e9bda38e6d ("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. Reported-by: Boqiao Fu <bfu@xxxxxxxxxx> Reported-by: Sebastian Mitterle <smitterl@xxxxxxxxxx> Fixes: e3e9bda38e6d ("s390/virtio_ccw: use DMA handle from DMA API") Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx> --- I know that checkpatch.pl complains about a missing 'Closes' tag. Unfortunately I don't have an appropriate URL at hand. @Sebastian, @Boqiao: do you have any suggetions? --- drivers/s390/virtio/virtio_ccw.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c index d7569f395559..d6491fc84e8c 100644 --- a/drivers/s390/virtio/virtio_ccw.c +++ b/drivers/s390/virtio/virtio_ccw.c @@ -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; base-commit: 83a7eefedc9b56fe7bfeff13b6c7356688ffa670 -- 2.40.1