The quilt patch titled
Subject: mm: check all swaps belong to same swap_cgroup in swap_pte_batch()
has been removed from the -mm tree. Its filename was
mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix.patch
This patch was dropped because it was folded into mm-attempt-to-batch-free-swap-entries-for-zap_pte_range.patch
------------------------------------------------------
From: Barry Song <v-songbaohua@xxxxxxxx>
Subject: mm: check all swaps belong to same swap_cgroup in swap_pte_batch()
Date: Fri, 16 Aug 2024 09:36:23 +1200
Right now, it is possible two folios are contiguous in swap slots but they
don't belong to one memcg. In this case, even we return a large nr, we
can't really batch free all slots.
Link: https://lkml.kernel.org/r/20240815215308.55233-1-21cnbao@xxxxxxxxx
Signed-off-by: Barry Song <v-songbaohua@xxxxxxxx>
Reported-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Reported-by: Chris Li <chrisl@xxxxxxxxxx>
Cc: Barry Song <baohua@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Kairui Song <kasong@xxxxxxxxxxx>
Cc: Kalesh Singh <kaleshsingh@xxxxxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/internal.h | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
--- a/mm/internal.h~mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix
+++ a/mm/internal.h
@@ -15,6 +15,7 @@
#include <linux/rmap.h>
#include <linux/swap.h>
#include <linux/swapops.h>
+#include <linux/swap_cgroup.h>
#include <linux/tracepoint-defs.h>
/* Internal core VMA manipulation functions. */
@@ -275,18 +276,22 @@ static inline int swap_pte_batch(pte_t *
{
pte_t expected_pte = pte_next_swp_offset(pte);
const pte_t *end_ptep = start_ptep + max_nr;
+ swp_entry_t entry = pte_to_swp_entry(pte);
pte_t *ptep = start_ptep + 1;
+ unsigned short cgroup_id;
VM_WARN_ON(max_nr < 1);
VM_WARN_ON(!is_swap_pte(pte));
- VM_WARN_ON(non_swap_entry(pte_to_swp_entry(pte)));
+ VM_WARN_ON(non_swap_entry(entry));
+ cgroup_id = lookup_swap_cgroup_id(entry);
while (ptep < end_ptep) {
pte = ptep_get(ptep);
if (!pte_same(pte, expected_pte))
break;
-
+ if (lookup_swap_cgroup_id(pte_to_swp_entry(pte)) != cgroup_id)
+ break;
expected_pte = pte_next_swp_offset(expected_pte);
ptep++;
}
_
Patches currently in -mm which might be from v-songbaohua@xxxxxxxx are
mm-rename-instances-of-swap_info_struct-to-meaningful-si.patch
mm-attempt-to-batch-free-swap-entries-for-zap_pte_range.patch
mm-count-the-number-of-anonymous-thps-per-size.patch
mm-count-the-number-of-partially-mapped-anonymous-thps-per-size.patch
mm-document-__gfp_nofail-must-be-blockable.patch
mm-warn-about-illegal-__gfp_nofail-usage-in-a-more-appropriate-location-and-manner.patch
mm-warn-about-illegal-__gfp_nofail-usage-in-a-more-appropriate-location-and-manner-fix.patch
