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No functional change intended. Signed-off-by: Uros Bizjak Cc: David Woodhouse Cc: Lu Baolu Cc: Joerg Roedel Cc: Will Deacon Cc: Robin Murphy Reviewed-by: Jason Gunthorpe --- drivers/iommu/intel/iommu.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 50eb9aed47cc..311073494f50 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -865,7 +865,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domai= n *domain, break; =20 if (!dma_pte_present(pte)) { - uint64_t pteval; + uint64_t pteval, tmp; =20 tmp_page =3D alloc_pgtable_page(domain->nid, gfp); =20 @@ -877,7 +877,8 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domai= n *domain, if (domain->use_first_level) pteval |=3D DMA_FL_PTE_XD | DMA_FL_PTE_US | DMA_FL_PTE_ACCESS; =20 - if (cmpxchg64(&pte->val, 0ULL, pteval)) + tmp =3D 0ULL; + if (!try_cmpxchg64(&pte->val, &tmp, pteval)) /* Someone else set it while we were thinking; use theirs. */ free_pgtable_page(tmp_page); else @@ -2128,8 +2129,8 @@ __domain_mapping(struct dmar_domain *domain, unsigned= long iov_pfn, /* We don't need lock here, nobody else * touches the iova range */ - tmp =3D cmpxchg64_local(&pte->val, 0ULL, pteval); - if (tmp) { + tmp =3D 0ULL; + if (!try_cmpxchg64_local(&pte->val, &tmp, pteval)) { static int dumps =3D 5; pr_crit("ERROR: DMA PTE for vPFN 0x%lx already set (to %llx not %llx)\n= ", iov_pfn, tmp, (unsigned long long)pteval); --=20 2.42.0