FAILED: patch "[PATCH] mm/hugetlb: add migration/hwpoisoned entry check in" failed to apply to 3.10-stable tree

Quoted 10 lines · On Wed, Mar 11, 2015 at 02:54:04PM +0100, [email protected] wrote:

The patch below does not apply to the 3.10-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

Quoted 7 lines

------------------ original commit in Linus's tree ------------------

From a8bda28d87c38c6aa93de28ba5d30cc18e865a11 Mon Sep 17 00:00:00 2001
From: Naoya Horiguchi <[email protected]>
Date: Wed, 11 Feb 2015 15:25:28 -0800
Subject: [PATCH] mm/hugetlb: add migration/hwpoisoned entry check in
hugetlb_change_protection

The conflict is trivial enough to resolve, so please apply the below one.

Thanks,
Naoya Horiguchi
---

Quoted 1 line

From 5babc2f225937be13d7c040d6d850128bd4f7ebf Mon Sep 17 00:00:00 2001

From: Naoya Horiguchi <[email protected]>
Date: Mon, 16 Mar 2015 16:04:05 +0900
Subject: [PATCH] mm/hugetlb: add migration/hwpoisoned entry check in
hugetlb_change_protection

There is a race condition between hugepage migration and change_protection(), where hugetlb_change_protection() doesn't care about migration entries and wrongly overwrites them. That causes unexpected results like kernel crash. HWPoison entries also can cause the same problem.

This patch adds is_hugetlb_entry_(migration|hwpoisoned) check in this function to do proper actions.

[[email protected]: resolve conflict to apply to v3.10.71]

Fixes 290408d4a2 ("hugetlb: hugepage migration core")

Signed-off-by Naoya Horiguchi <[email protected]>

Cc Hugh Dickins <[email protected]>

Cc James Hogan <[email protected]>

Cc David Rientjes <[email protected]>

Cc Mel Gorman <[email protected]>

Cc Johannes Weiner <[email protected]>

Cc Michal Hocko <[email protected]>

Cc Rik van Riel <[email protected]>

Cc Andrea Arcangeli <[email protected]>

Cc Luiz Capitulino <[email protected]>

Cc Nishanth Aravamudan <[email protected]>

Cc Lee Schermerhorn <[email protected]>

Cc Steve Capper <[email protected]>

Cc <[email protected]> [2.6.36+]

Signed-off-by Andrew Morton <[email protected]>

Signed-off-by Linus Torvalds <[email protected]>

---
 mm/hugetlb.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

mm/hugetlb.c +7 -1

index 7de4f67c81fe..e25e32f5e0e1 100644
@@ -3116,7 +3116,26 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
 			pages++;
 			continue;
 		}
-		if (!huge_pte_none(huge_ptep_get(ptep))) {
+		pte = huge_ptep_get(ptep);
+		if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) {
+			spin_unlock(ptl);
+			continue;
+		}
+		if (unlikely(is_hugetlb_entry_migration(pte))) {
+			swp_entry_t entry = pte_to_swp_entry(pte);