+ memcg-vmalloc-simplify-memcg_vmalloc-updates-fix.patch added to mm-new branch

+ memcg-vmalloc-simplify-memcg_vmalloc-updates-fix.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: memcg: simplify MEMCG_VMALLOC updates - fix
has been added to the -mm mm-new branch.  Its filename is
     memcg-vmalloc-simplify-memcg_vmalloc-updates-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/memcg-vmalloc-simplify-memcg_vmalloc-updates-fix.patch

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

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------------------------------------------------------
From: Shakeel Butt <shakeel.butt@linux.dev>
Subject: memcg: simplify MEMCG_VMALLOC updates - fix
Date: Fri, 4 Apr 2025 10:41:52 -0700

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Link: https://lkml.kernel.org/r/bmlkdbqgwboyqrnxyom7n52fjmo76ux77jhqw5odc6c6dfon3h@zdylwtmlywbt
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
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: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

--- a/mm/vmalloc.c~memcg-vmalloc-simplify-memcg_vmalloc-updates-fix
+++ a/mm/vmalloc.c
@@ -3370,6 +3370,7 @@ void vfree(const void *addr)
 
 	if (unlikely(vm->flags & VM_FLUSH_RESET_PERMS))
 		vm_reset_perms(vm);
+	/* All pages of vm should be charged to same memcg, so use first one. */
 	if (vm->nr_pages && !(vm->flags & VM_MAP_PUT_PAGES))
 		mod_memcg_page_state(vm->pages[0], MEMCG_VMALLOC, -vm->nr_pages);
 	for (i = 0; i < vm->nr_pages; i++) {
@@ -3671,6 +3672,7 @@ static void *__vmalloc_area_node(struct
 		node, page_order, nr_small_pages, area->pages);
 
 	atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
+	/* All pages of vm should be charged to same memcg, so use first one. */
 	if (gfp_mask & __GFP_ACCOUNT && area->nr_pages)
 		mod_memcg_page_state(area->pages[0], MEMCG_VMALLOC,
 				     area->nr_pages);
_

Patches currently in -mm which might be from shakeel.butt@linux.dev are

memcg-vmalloc-simplify-memcg_vmalloc-updates.patch
memcg-vmalloc-simplify-memcg_vmalloc-updates-fix.patch