+ mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch added to mm-unstable branch

+ mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch

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

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days

------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix
Date: Mon Aug  3 05:44:48 PM PDT 2026

use ARRAY_SIZE to dimension ratio[]

Cc: Brendan Jackman <jackmanb@google.com>
Cc: Jianlin Shi <shijianlin11@foxmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_alloc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/page_alloc.c~mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix
+++ a/mm/page_alloc.c
@@ -6926,7 +6926,7 @@ static int lowmem_reserve_ratio_sysctl_h
 		int write, void *buffer, size_t *length, loff_t *ppos)
 {
 	struct ctl_table tmp = *table;
-	int ratio[MAX_NR_ZONES];
+	int ratio[ARRAY_SIZE(sysctl_lowmem_reserve_ratio)];
 	int rc;
 
 	if (!write)
_

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

mm-drop-stale-folio_ref_count==1-check-in-do_swap_page-reuse-logic-fix.patch
mm-hmm-make-config_hmm_mirror-select-config_mmu_notifier.patch
mm-vma-add-and-use-vma__pgoff-fix.patch
alloc_tag-add-ioctl-to-proc-allocinfo-fix.patch
mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch
drivers-media-v4l2-core-v4l2-vp9c-reduce-inlining.patch

+ mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch

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

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days

------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix
Date: Thu Aug  6 02:14:15 PM PDT 2026

add comment, per hannes

Link: https://lore.kernel.org/anSRGASe5FIrqwlg@cmpxchg.org
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Jianlin Shi <shijianlin11@foxmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Joel Granados <joel.granados@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_alloc.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/mm/page_alloc.c~mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix
+++ a/mm/page_alloc.c
@@ -6932,6 +6932,10 @@ static int lowmem_reserve_ratio_sysctl_h
 	if (!write)
 		return proc_dointvec_minmax(table, write, buffer, length, ppos);
 
+	/*
+	 * proc_dointvec_max() works incrementally. Use a buffer and only set
+	 * the values if all of them parse cleanly.
+	 */
 	memcpy(ratio, sysctl_lowmem_reserve_ratio, sizeof(ratio));
 	tmp.data = ratio;
 
_

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

alloc_tag-add-ioctl-to-proc-allocinfo-fix.patch
mm-page_alloc-only-update-lowmem_reserve_ratio-on-sysctl-write-fix.patch
selftests-mm-fix-soft-dirty-kselftest-supported-check-fix.patch
drivers-media-v4l2-core-v4l2-vp9c-reduce-inlining.patch