+ mm-vmscan-propagate-real-error-code-from-per-node-proactive-reclaim.patch added to mm-new branch

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

The patch titled
     Subject: mm: vmscan: propagate real error code from per-node proactive reclaim
has been added to the -mm mm-new branch.  Its filename is
     mm-vmscan-propagate-real-error-code-from-per-node-proactive-reclaim.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-propagate-real-error-code-from-per-node-proactive-reclaim.patch

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

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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------------------------------------------------------
From: Ridong Chen <chenridong@xiaomi.com>
Subject: mm: vmscan: propagate real error code from per-node proactive reclaim
Date: Fri, 17 Jul 2026 19:32:59 +0800

It has been observed that per-node proactive reclaim always returns
-EAGAIN when any error occurs.  As discussed in the mailing list [1], the
interface should distinguish between cases where no reclaimable memory is
left and where another entity is concurrently using the same interface. 
Propagate the real error code, consistent with how memcg proactive reclaim
handles errors.

Link: https://lore.kernel.org/20260717113300.214717-3-ridong.chen@linux.dev
Link: https://lore.kernel.org/all/20250717235604.2atyx2aobwowpge3@offworld/T/#m3514718be82a31b05726a49da9b61fbfc69a589e [1]
Fixes: b980077899ea ("mm: introduce per-node proactive reclaim interface")
Signed-off-by: Ridong Chen <chenridong@xiaomi.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kairui Song <kasong@tencent.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <qi.zheng@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zhongkun He <hezhongkun.hzk@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

--- a/mm/vmscan.c~mm-vmscan-propagate-real-error-code-from-per-node-proactive-reclaim
+++ a/mm/vmscan.c
@@ -8008,7 +8008,7 @@ static ssize_t reclaim_store(struct devi
 	int ret, nid = dev->id;
 
 	ret = user_proactive_reclaim((char *)buf, NULL, NODE_DATA(nid));
-	return ret ? -EAGAIN : count;
+	return ret ? ret : count;
 }
 
 static DEVICE_ATTR_WO(reclaim);
_

Patches currently in -mm which might be from chenridong@xiaomi.com are

mm-vmscan-fix-anon-only-reclaim-evicting-file-pages-when-swappiness=max.patch
mm-vmscan-propagate-real-error-code-from-per-node-proactive-reclaim.patch
mm-vmscan-drop-unused-gfp_mask-parameter-from-__node_reclaim.patch