4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Alexey Kardashevskiy <[email protected]> [ Upstream commit 930a42ded3fede7ca3acafc9153f4f2d0f56a92c ] If a container already has a group attached, attaching a new group should just program already created IOMMU tables to the hardware via the iommu_table_group_ops::set_window() callback. However commit 6f01cc692a16 ("vfio/spapr: Add a helper to create default DMA window") did not just simplify the code but also removed the set_window() calls in the case of attaching groups to a container which already has tables so it broke VFIO PCI hotplug. This reverts set_window() bits in tce_iommu_take_ownership_ddw(). Fixes: 6f01cc692a16 ("vfio/spapr: Add a helper to create default DMA window") Signed-off-by: Alexey Kardashevskiy <[email protected]> Reviewed-by: David Gibson <[email protected]> Signed-off-by: Alex Williamson <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/vfio/vfio_iommu_spapr_tce.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -1246,6 +1246,8 @@ static void tce_iommu_release_ownership_ static long tce_iommu_take_ownership_ddw(struct tce_container *container, struct iommu_table_group *table_group) { + long i, ret = 0; + if (!table_group->ops->create_table || !table_group->ops->set_window || !table_group->ops->release_ownership) { WARN_ON_ONCE(1); @@ -1254,7 +1256,27 @@ static long tce_iommu_take_ownership_ddw table_group->ops->take_ownership(table_group); + /* Set all windows to the new group */ + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { + struct iommu_table *tbl = container->tables[i]; + + if (!tbl) + continue; + + ret = table_group->ops->set_window(table_group, i, tbl); + if (ret) + goto release_exit; + } + return 0; + +release_exit: + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) + table_group->ops->unset_window(table_group, i); + + table_group->ops->release_ownership(table_group); + + return ret; } static int tce_iommu_attach_group(void *iommu_data,
