diff options
| author | Jason Gunthorpe <jgg@nvidia.com> | 2022-05-19 19:03:48 +0200 |
|---|---|---|
| committer | Alex Williamson <alex.williamson@redhat.com> | 2022-05-23 18:27:43 +0200 |
| commit | a3da1ab6fbea7d5cbcb796f62c8771d8ebd7282a (patch) | |
| tree | 2964b347cc8c4fdfd3441df34ddfc02d8d6e52a9 /drivers/vfio/vfio.c | |
| parent | vfio/pci: Move the unused device into low power state with runtime PM (diff) | |
| download | linux-a3da1ab6fbea7d5cbcb796f62c8771d8ebd7282a.tar.xz linux-a3da1ab6fbea7d5cbcb796f62c8771d8ebd7282a.zip | |
vfio: Do not manipulate iommu dma_owner for fake iommu groups
Since asserting dma ownership now causes the group to have its DMA blocked
the iommu layer requires a working iommu. This means the dma_owner APIs
cannot be used on the fake groups that VFIO creates. Test for this and
avoid calling them.
Otherwise asserting dma ownership will fail for VFIO mdev devices as a
BLOCKING iommu_domain cannot be allocated due to the NULL iommu ops.
Fixes: 0286300e6045 ("iommu: iommu_group_claim_dma_owner() must always assign a domain")
Reported-by: Eric Farman <farman@linux.ibm.com>
Tested-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/0-v1-9cfc47edbcd4+13546-vfio_dma_owner_fix_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'drivers/vfio/vfio.c')
| -rw-r--r-- | drivers/vfio/vfio.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index cfcff7764403..f5ed03897210 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -927,7 +927,8 @@ static void __vfio_group_unset_container(struct vfio_group *group) driver->ops->detach_group(container->iommu_data, group->iommu_group); - iommu_group_release_dma_owner(group->iommu_group); + if (group->type == VFIO_IOMMU) + iommu_group_release_dma_owner(group->iommu_group); group->container = NULL; group->container_users = 0; @@ -1001,9 +1002,11 @@ static int vfio_group_set_container(struct vfio_group *group, int container_fd) goto unlock_out; } - ret = iommu_group_claim_dma_owner(group->iommu_group, f.file); - if (ret) - goto unlock_out; + if (group->type == VFIO_IOMMU) { + ret = iommu_group_claim_dma_owner(group->iommu_group, f.file); + if (ret) + goto unlock_out; + } driver = container->iommu_driver; if (driver) { @@ -1011,7 +1014,9 @@ static int vfio_group_set_container(struct vfio_group *group, int container_fd) group->iommu_group, group->type); if (ret) { - iommu_group_release_dma_owner(group->iommu_group); + if (group->type == VFIO_IOMMU) + iommu_group_release_dma_owner( + group->iommu_group); goto unlock_out; } } |