6.9-stable review patch. If anyone has any objections, please let me know.
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From: Halil Pasic pasic@linux.ibm.com
[ Upstream commit d8354a1de2c4cc693812f6130fc922537a59217d ]
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.
Fixes: e3e9bda38e6d ("s390/virtio_ccw: use DMA handle from DMA API") Reported-by: Boqiao Fu bfu@redhat.com Reported-by: Sebastian Mitterle smitterl@redhat.com Closes: https://issues.redhat.com/browse/RHEL-39983 Tested-by: Thomas Huth thuth@redhat.com Reviewed-by: Eric Farman farman@linux.ibm.com Signed-off-by: Halil Pasic pasic@linux.ibm.com Link: https://lore.kernel.org/r/20240611214716.1002781-1-pasic@linux.ibm.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 d7569f3955591..d6491fc84e8c5 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;