Patch "iommu/io-pgtable-arm: Ensure we free the final level on teardown" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

iommu/io-pgtable-arm: Ensure we free the final level on teardown

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
iommu-io-pgtable-arm-ensure-we-free-the-final-level-on-teardown.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Will Deacon <[email protected]>
Date: Tue, 15 Dec 2015 16:08:12 +0000
Subject: iommu/io-pgtable-arm: Ensure we free the final level on teardown

From: Will Deacon <[email protected]>

commit 12c2ab09571e8aae3a87da2a4a452632a5fac1e5 upstream.

When tearing down page tables, we return early for the final level since we know that we won't have any table pointers to follow. Unfortunately, this also means that we forget to free the final level, so we end up leaking memory.

Fix the issue by always freeing the current level, but just don't bother to iterate over the ptes if we're at the final level.

---
 drivers/iommu/io-pgtable-arm.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

@@ -405,17 +405,18 @@ static void __arm_lpae_free_pgtable(stru
 	arm_lpae_iopte *start, *end;
 	unsigned long table_size;
 
-	/* Only leaf entries at the last level */
-	if (lvl == ARM_LPAE_MAX_LEVELS - 1)
-		return;
-
 	if (lvl == ARM_LPAE_START_LVL(data))
 		table_size = data->pgd_size;
 	else
 		table_size = 1UL << data->pg_shift;
 
 	start = ptep;
-	end = (void *)ptep + table_size;
+
+	/* Only leaf entries at the last level */
+	if (lvl == ARM_LPAE_MAX_LEVELS - 1)
+		end = ptep;
+	else
+		end = (void *)ptep + table_size;
 
 	while (ptep != end) {
 		arm_lpae_iopte pte = *ptep++;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/iommu-io-pgtable-arm-ensure-we-free-the-final-level-on-teardown.patch