3.13-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yifan Zhang <[email protected]>

commit 97a644208d1a08b7104d1fe2ace8cef011222711 upstream.

The ARM SMMU driver's population of puds and pmds is broken, since we
iterate over the next level of table repeatedly setting the current
level descriptor to point at the pmd being initialised. This is clearly
wrong when dealing with multiple pmds/puds.

This patch fixes the problem by moving the pud/pmd population out of the
loop and instead performing it when we allocate the next level (like we
correctly do for ptes already). The starting address for the next level
is then calculated prior to entering the loop.

Signed-off-by: Yifan Zhang <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/iommu/arm-smmu.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1317,6 +1317,11 @@ static int arm_smmu_alloc_init_pmd(struc
                pmd = pmd_alloc_one(NULL, addr);
                if (!pmd)
                        return -ENOMEM;
+
+               pud_populate(NULL, pud, pmd);
+               arm_smmu_flush_pgtable(smmu, pud, sizeof(*pud));
+
+               pmd += pmd_index(addr);
        } else
 #endif
                pmd = pmd_offset(pud, addr);
@@ -1325,8 +1330,6 @@ static int arm_smmu_alloc_init_pmd(struc
                next = pmd_addr_end(addr, end);
                ret = arm_smmu_alloc_init_pte(smmu, pmd, addr, end, pfn,
                                              flags, stage);
-               pud_populate(NULL, pud, pmd);
-               arm_smmu_flush_pgtable(smmu, pud, sizeof(*pud));
                phys += next - addr;
        } while (pmd++, addr = next, addr < end);
 
@@ -1346,6 +1349,11 @@ static int arm_smmu_alloc_init_pud(struc
                pud = pud_alloc_one(NULL, addr);
                if (!pud)
                        return -ENOMEM;
+
+               pgd_populate(NULL, pgd, pud);
+               arm_smmu_flush_pgtable(smmu, pgd, sizeof(*pgd));
+
+               pud += pud_index(addr);
        } else
 #endif
                pud = pud_offset(pgd, addr);
@@ -1354,8 +1362,6 @@ static int arm_smmu_alloc_init_pud(struc
                next = pud_addr_end(addr, end);
                ret = arm_smmu_alloc_init_pmd(smmu, pud, addr, next, phys,
                                              flags, stage);
-               pgd_populate(NULL, pud, pgd);
-               arm_smmu_flush_pgtable(smmu, pgd, sizeof(*pgd));
                phys += next - addr;
        } while (pud++, addr = next, addr < end);
 


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