From a3906855890d94736d240f0f637585c1470d8d02 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Mon, 11 Feb 2019 18:49:17 +1100 Subject: vfio/spapr_tce: Skip unsetting already unset table VFIO TCE IOMMU v2 owns IOMMU tables. When we detach an IOMMU group from a container, we need to unset these tables from the group which we do by calling unset_window(). We also unset tables when removing a DMA window via the VFIO_IOMMU_SPAPR_TCE_REMOVE ioctl. The window removal checks if the table actually exists (hidden inside tce_iommu_find_table()) but the group detaching does not so the user may see duplicating messages: pci 0009:03 : [PE# fd] Removing DMA window #0 pci 0009:03 : [PE# fd] Removing DMA window #1 pci 0009:03 : [PE# fd] Removing DMA window #0 pci 0009:03 : [PE# fd] Removing DMA window #1 At the moment this is not a problem as the second invocation of unset_window() writes zeroes to the HW registers again and exits early as there is no table. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Signed-off-by: Alex Williamson --- drivers/vfio/vfio_iommu_spapr_tce.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/vfio') diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index c424913324e3..8dbb270998f4 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -1235,7 +1235,8 @@ static void tce_iommu_release_ownership_ddw(struct tce_container *container, } for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) - table_group->ops->unset_window(table_group, i); + if (container->tables[i]) + table_group->ops->unset_window(table_group, i); table_group->ops->release_ownership(table_group); } -- cgit v1.2.3-55-g7522