[PATCH 4.0 32/55] iommu/amd: Handle large pages correctly in free_pagetable

Greg Kroah-Hartman
2015-07-08T08:08:57Z

From: Joerg Roedel <jroedel@suse.de>

commit 0b3fff54bc01e8e6064d222a33e6fa7adabd94cd upstream.

Make sure that we are skipping over large PTEs while walking
the page-table tree.

Fixes: 5c34c403b723 ("iommu/amd: Fix memory leak in free_pagetable")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/iommu/amd_iommu.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1870,9 +1870,15 @@ static void free_pt_##LVL (unsigned long
pt = (u64 *)__pt; \
\
for (i = 0; i < 512; ++i) { \
+ /* PTE present? */ \
if (!IOMMU_PTE_PRESENT(pt[i])) \
continue; \
\
+ /* Large PTE? */ \
+ if (PM_PTE_LEVEL(pt[i]) == 0 || \
+ PM_PTE_LEVEL(pt[i]) == 7) \
+ continue; \
+ \
p = (unsigned long)IOMMU_PTE_PAGE(pt[i]); \
FN(p); \
} \