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

The patch titled
     Subject: mm: vmscan: propagate real error code from per-node proactive reclaim
has been added to the -mm mm-unstable 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-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Ridong Chen <[email protected]>
Subject: mm: vmscan: propagate real error code from per-node proactive reclaim
Date: Fri, 24 Jul 2026 11:34:33 +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/[email protected]
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 <[email protected]>
Reviewed-by: Muchun Song <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Acked-by: Shakeel Butt <[email protected]>
Reviewed-by: Qi Zheng <[email protected]>
Reviewed-by: Barry Song <[email protected]>
Cc: Axel Rasmussen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Kairui Song <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Wei Xu <[email protected]>
Cc: Yuanchu Xie <[email protected]>
Cc: Zhongkun He <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 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
@@ -8024,7 +8024,7 @@ 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 [email protected] 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
mm-mglru-fix-anon-only-reclaim-evicting-file-pages-when-swappiness=max.patch
memcg-move-mem_cgroup_swappiness-and-vm_swappiness-to-mm-swaph.patch
mm-vmscan-fix-node-reclaim-ignoring-swappiness-parameter.patch