This is a note to let you know that I've just added the patch titled vfio/powerpc/spapr_tce: Enforce IOMMU type compatibility check to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: vfio-powerpc-spapr_tce-enforce-iommu-type-compatibility-check.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sun Mar 18 16:55:33 CET 2018 From: Alexey Kardashevskiy <aik@xxxxxxxxx> Date: Fri, 24 Mar 2017 17:44:06 +1100 Subject: vfio/powerpc/spapr_tce: Enforce IOMMU type compatibility check From: Alexey Kardashevskiy <aik@xxxxxxxxx> [ Upstream commit 1282ba7fc28dbc66c3f0e4aaafaaa228361d1ae5 ] The existing SPAPR TCE driver advertises both VFIO_SPAPR_TCE_IOMMU and VFIO_SPAPR_TCE_v2_IOMMU types to the userspace and the userspace usually picks the v2. Normally the userspace would create a container, attach an IOMMU group to it and only then set the IOMMU type (which would normally be v2). However a specific IOMMU group may not support v2, in other words it may not implement set_window/unset_window/take_ownership/ release_ownership and such a group should not be attached to a v2 container. This adds extra checks that a new group can do what the selected IOMMU type suggests. The userspace can then test the return value from ioctl(VFIO_SET_IOMMU, VFIO_SPAPR_TCE_v2_IOMMU) and try VFIO_SPAPR_TCE_IOMMU. Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/vfio/vfio_iommu_spapr_tce.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -1332,8 +1332,16 @@ static int tce_iommu_attach_group(void * if (!table_group->ops || !table_group->ops->take_ownership || !table_group->ops->release_ownership) { + if (container->v2) { + ret = -EPERM; + goto unlock_exit; + } ret = tce_iommu_take_ownership(container, table_group); } else { + if (!container->v2) { + ret = -EPERM; + goto unlock_exit; + } ret = tce_iommu_take_ownership_ddw(container, table_group); if (!tce_groups_attached(container) && !container->tables[0]) container->def_window_pending = true; Patches currently in stable-queue which might be from aik@xxxxxxxxx are queue-4.9/vfio-spapr_tce-check-kzalloc-return-when-preregistering-memory.patch queue-4.9/vfio-powerpc-spapr_tce-enforce-iommu-type-compatibility-check.patch