+ mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix-2.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: check all swaps belong to same swap_cgroup in swap_pte_batch() fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix-2.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix-2.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Hugh Dickins <hughd@google.com>
Subject: mm: check all swaps belong to same swap_cgroup in swap_pte_batch() fix
Date: Sun, 25 Aug 2024 13:09:46 -0700 (PDT)

mm-unstable swap_pte_batch() adds a new usage of lookup_swap_cgroup_id(),
which crashes if CONFIG_MEMCG kernel booted with "cgroup_disable=memory":
it now needs a mem_cgroup_disabled() check.

Link: https://lkml.kernel.org/r/33f34a88-0130-5444-9b84-93198eeb50e7@google.com
Fixes: 92b50df44566 ("mm: check all swaps belong to same swap_cgroup in swap_pte_batch()")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Barry Song <baohua@kernel.org>
Cc: Barry Song <v-songbaohua@oppo.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swap_cgroup.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/swap_cgroup.c~mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix-2
+++ a/mm/swap_cgroup.c
@@ -161,6 +161,8 @@ unsigned short swap_cgroup_record(swp_en
  */
 unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
 {
+	if (mem_cgroup_disabled())
+		return 0;
 	return lookup_swap_cgroup(ent, NULL)->id;
 }
 
_

Patches currently in -mm which might be from hughd@google.com are

mm-attempt-to-batch-free-swap-entries-for-zap_pte_range-fix-2.patch
mm-shmem-split-large-entry-if-the-swapin-folio-is-not-large-fix.patch
mm-shmem-support-large-folio-swap-out-fix.patch
mm-shmem-fix-minor-off-by-one-in-shrinkable-calculation.patch
mm-shmem-extend-shmem_unused_huge_shrink-to-all-sizes.patch