[folded-merged] memcg-v1-no-need-for-memcg-locking-for-mglru-fix.patch removed from -mm tree

[folded-merged] memcg-v1-no-need-for-memcg-locking-for-mglru-fix.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: memcg-v1-no-need-for-memcg-locking-for-mglru-fix
has been removed from the -mm tree.  Its filename was
     memcg-v1-no-need-for-memcg-locking-for-mglru-fix.patch

This patch was dropped because it was folded into memcg-v1-no-need-for-memcg-locking-for-mglru.patch

------------------------------------------------------
From: Yu Zhao <yuzhao@google.com>
Subject: memcg-v1-no-need-for-memcg-locking-for-mglru-fix
Date: Mon, 4 Nov 2024 10:30:29 -0700

remove !rcu_read_lock_held() assertion

  WARNING: CPU: 0 PID: 85 at mm/vmscan.c:3140 folio_update_gen+0x23d/0x250 mm/vmscan.c:3140
  ...

This assertion is incorrect after this patch series that has removed the
charge migration and has removed mem_cgroup_trylock_pages() /
mem_cgroup_unlock_pages() from the caller of this function
(folio_update_gen()).

The assertion was caused by the patch in this thread.  It used to assert
that a folio must be protected from charge migration.  Charge migration is
removed by this series, and as part of the effort, this patch removes the
RCU lock.

Link: https://lkml.kernel.org/r/ZykEtcHrQRq-KrBC@google.com
Link: https://syzkaller.appspot.com/bug?extid=24f45b8beab9788e467e
Link: https://lore.kernel.org/lkml/67294349.050a0220.701a.0010.GAE@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmscan.c |    1 -
 1 file changed, 1 deletion(-)

--- a/mm/vmscan.c~memcg-v1-no-need-for-memcg-locking-for-mglru-fix
+++ a/mm/vmscan.c
@@ -3137,7 +3137,6 @@ static int folio_update_gen(struct folio
 	unsigned long new_flags, old_flags = READ_ONCE(folio->flags);
 
 	VM_WARN_ON_ONCE(gen >= MAX_NR_GENS);
-	VM_WARN_ON_ONCE(!rcu_read_lock_held());
 
 	do {
 		/* lru_gen_del_folio() has isolated this page? */
_

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

mm-page_alloc-keep-track-of-free-highatomic.patch
memcg-v1-no-need-for-memcg-locking-for-mglru.patch

[folded-merged] memcg-v1-no-need-for-memcg-locking-for-mglru-fix.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: memcg-v1-no-need-for-memcg-locking-for-mglru-fix
has been removed from the -mm tree.  Its filename was
     memcg-v1-no-need-for-memcg-locking-for-mglru-fix.patch

This patch was dropped because it was folded into memcg-v1-no-need-for-memcg-locking-for-mglru.patch

------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: memcg-v1-no-need-for-memcg-locking-for-mglru-fix
Date: Fri Oct 25 06:28:06 PM PDT 2024

remove now-unused local:

mm/vmscan.c: In function 'walk_mm':
mm/vmscan.c:3652:28: error: unused variable 'memcg' [-Werror=unused-variable]
 3652 |         struct mem_cgroup *memcg = lruvec_memcg(lruvec);
      |                            ^~~~~
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmscan.c |    2 --
 1 file changed, 2 deletions(-)

--- a/mm/vmscan.c~memcg-v1-no-need-for-memcg-locking-for-mglru-fix
+++ a/mm/vmscan.c
@@ -3649,10 +3649,8 @@ static void walk_mm(struct mm_struct *mm
 		.p4d_entry = walk_pud_range,
 		.walk_lock = PGWALK_RDLOCK,
 	};
-
 	int err;
 	struct lruvec *lruvec = walk->lruvec;
-	struct mem_cgroup *memcg = lruvec_memcg(lruvec);
 
 	walk->next_addr = FIRST_USER_ADDRESS;
 
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

mm-page_alloc-keep-track-of-free-highatomic-fix.patch
mm-refactor-arch_calc_vm_flag_bits-and-arm64-mte-handling-fix.patch
mm-fix-__wp_page_copy_user-fallback-path-for-remote-mm-fix.patch
mm-memoryc-remove-stray-newline-at-top-of-file.patch
memcg-v1-no-need-for-memcg-locking-for-mglru.patch
mm-vma-the-pgoff-is-correct-if-can_merge_right-fix.patch
memcg-workingset-remove-folio_memcg_rcu-usage-fix.patch
bootmem-stop-using-page-index-fix.patch
vma-detect-infinite-loop-in-vma-tree-fix.patch
maple_tree-add-a-test-checking-storing-null-fix.patch
fs-proc-kcorec-fix-coccinelle-reported-error-instances-fix.patch