From: Lu Baolu baolu.lu@linux.intel.com
[ Upstream commit 857f081426e5aa38313426c13373730f1345fe95 ]
Address field in device TLB invalidation descriptor is qualified by the S field. If S field is zero, a single page at page address specified by address [63:12] is requested to be invalidated. If S field is set, the least significant bit in the address field with value 0b (say bit N) indicates the invalidation address range. The spec doesn't require the address [N - 1, 0] to be cleared, hence remove the unnecessary WARN_ON_ONCE().
Otherwise, the caller might set "mask = MAX_AGAW_PFN_WIDTH" in order to invalidating all the cached mappings on an endpoint, and below overflow error will be triggered.
[...] UBSAN: Undefined behaviour in drivers/iommu/dmar.c:1354:3 shift exponent 64 is too large for 64-bit type 'long long unsigned int' [...]
Reported-and-tested-by: Frank fgndev@posteo.de Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/dmar.c | 1 - 1 file changed, 1 deletion(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 7f9824b0609e7..72994d67bc5b9 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -1345,7 +1345,6 @@ void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid, struct qi_desc desc;
if (mask) { - WARN_ON_ONCE(addr & ((1ULL << (VTD_PAGE_SHIFT + mask)) - 1)); addr |= (1ULL << (VTD_PAGE_SHIFT + mask - 1)) - 1; desc.high = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE; } else