From: Robin Murphy robin.murphy@arm.com
commit 6833b8f2e19945a41e4d5efd8c6d9f4cae9a5b7d upstream
When io-pgtable unmaps a whole table, rather than waste time walking it to find the leaf entries to invalidate exactly, it simply expects .tlb_flush_walk with nominal last-level granularity to invalidate any leaf entries at higher intermediate levels as well. This works fine with page-based invalidation, but with range commands we need to be careful with the TTL hint - unconditionally setting it based on the given level 3 granule means that an invalidation for a level 1 table would strictly not be required to affect level 2 block entries. It's easy to comply with the expected behaviour by simply not setting the TTL hint for non-leaf invalidations, so let's do that.
Signed-off-by: Robin Murphy robin.murphy@arm.com Link: https://lore.kernel.org/r/b409d9a17c52dc0db51faee91d92737bb7975f5b.168563745... Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Easwar Hariharan eahariha@linux.microsoft.com --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 340ef116d574..67845f8e1df9 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -1884,8 +1884,13 @@ static void __arm_smmu_tlb_inv_range(struct arm_smmu_cmdq_ent *cmd, /* Convert page size of 12,14,16 (log2) to 1,2,3 */ cmd->tlbi.tg = (tg - 10) / 2;
- /* Determine what level the granule is at */ - cmd->tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3)); + /* + * Determine what level the granule is at. For non-leaf, io-pgtable + * assumes .tlb_flush_walk can invalidate multiple levels at once, + * so ignore the nominal last-level granule and leave TTL=0. + */ + if (cmd->tlbi.leaf) + cmd->tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
num_pages = size >> tg; }