[PATCH] iommu/vt-d: Fix the size calculation of pasid table

[Xunlei Pang]

According to the vt-d spec, the size of pasid (state) entry is 8B
which equals 3 in power of 2, the number of pasid (state) entries
is (ecap_pss + 1) in power of 2.

Thus the right size of pasid (state) table in power of 2 should be
ecap_pss(iommu->ecap) plus "1+3=4" other than 7.

Signed-off-by: Xunlei Pang <xlpang@xxxxxxxxxx>
---
 drivers/iommu/intel-svm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 8ebb353..cfa75c2 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -39,7 +39,7 @@ int intel_svm_alloc_pasid_tables(struct intel_iommu *iommu)
 	struct page *pages;
 	int order;
 
-	order = ecap_pss(iommu->ecap) + 7 - PAGE_SHIFT;
+	order = ecap_pss(iommu->ecap) + 4 - PAGE_SHIFT;
 	if (order < 0)
 		order = 0;
 
-- 
1.8.3.1