From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9ECF338CFFE; Mon, 6 Apr 2026 18:14:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775499263; cv=none; b=HRUqIqNtXrLlBenkLgtqtB67IqQD1QCyB8rAazAPi/joyKPifTfxMrW3TVLHCKRI0NaBAyhWks6kFlznlDKHr88BfI3PL2rh3PdU7QWkEtr0dxUQ22HL/nUYOSCeCjp4rtoAfTbSFQOj3q2uy0WFLZppdw8uby+4BxUUj2qnPyY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775499263; c=relaxed/simple; bh=j6jsV0fJuS8L00HjM1qF18Ze0Unhn2fonu8m+hvR3sI=; h=Date:To:From:Subject:Message-Id; b=TE6YT7/QGDAqHr/keP1CJ/kMqvzXhJeeLvnTyKwWkT2RECBHWSE7/TQVuS4zu3zmi1nEK/wNRPY5/otDK4WAekDsg+zueLXsdJ8NqFg1vrtnx6DXQO+RmYx0n97w+bD8aYyZ0hZyMd31p/jC/ZCz6nfgAodYEBsAZHRf+3chm1w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=rCQ0TrJH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="rCQ0TrJH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D090C4CEF7; Mon, 6 Apr 2026 18:14:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1775499263; bh=j6jsV0fJuS8L00HjM1qF18Ze0Unhn2fonu8m+hvR3sI=; h=Date:To:From:Subject:From; b=rCQ0TrJH00TiQtPatwVYS34vAVLfW4NqladKW9Ra1sgRUJEtCnW19O3vNr5vV+Wj4 LZHy5NZ+BVIMsKdvuTudzI9e5KF0gwuIf/kgYUU4Qxp2iDS8vY9iHT1Hvn4oFl5J1Q t5tkP7jnWdfesSKR53iyn9nZdzRvsLhBo3iyhox8= Date: Mon, 06 Apr 2026 11:14:22 -0700 To: mm-commits@vger.kernel.org,vbabka@suse.cz,vbabka@kernel.org,stable@vger.kernel.org,osalvador@suse.de,joshua.hahnjy@gmail.com,harry@kernel.org,david@kernel.org,hao.li@linux.dev,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-hotfixes-stable] mm-memory_hotplug-maintain-n_normal_memory-during-hotplug.patch removed from -mm tree Message-Id: <20260406181423.4D090C4CEF7@smtp.kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/memory_hotplug: maintain N_NORMAL_MEMORY during hotplug has been removed from the -mm tree. Its filename was mm-memory_hotplug-maintain-n_normal_memory-during-hotplug.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Hao Li Subject: mm/memory_hotplug: maintain N_NORMAL_MEMORY during hotplug Date: Mon, 30 Mar 2026 11:57:49 +0800 N_NORMAL_MEMORY is initialized from zone population at boot, but memory hotplug currently only updates N_MEMORY. As a result, a node that gains normal memory via hotplug can remain invisible to users iterating over N_NORMAL_MEMORY, while a node that loses its last normal memory can stay incorrectly marked as such. The most visible effect is that /sys/devices/system/node/has_normal_memory does not report a node even after that node has gained normal memory via hotplug. Also, list_lru-based shrinkers can undercount objects on such a node and may skip reclaim on that node entirely, which can lead to a higher memory footprint than expected. Restore N_NORMAL_MEMORY maintenance directly in online_pages() and offline_pages(). Set the bit when a node that currently lacks normal memory onlines pages into a zone <= ZONE_NORMAL, and clear it when offlining removes the last present pages from zones <= ZONE_NORMAL. This restores the intended semantics without bringing back the old status_change_nid_normal notifier plumbing which was removed in 8d2882a8edb8. Current users that benefit include list_lru, zswap, nfsd filecache, hugetlb_cgroup, and has_normal_memory sysfs reporting. Link: https://lkml.kernel.org/r/20260330035941.518186-1-hao.li@linux.dev Fixes: 8d2882a8edb8 ("mm,memory_hotplug: remove status_change_nid_normal and update documentation") Signed-off-by: Hao Li Reviewed-by: Harry Yoo (Oracle) Acked-by: Vlastimil Babka (SUSE) Reviewed-by: Joshua Hahn Acked-by: David Hildenbrand (Arm) Cc: Oscar Salvador Cc: Vlastimil Babka Cc: Signed-off-by: Andrew Morton --- mm/memory_hotplug.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) --- a/mm/memory_hotplug.c~mm-memory_hotplug-maintain-n_normal_memory-during-hotplug +++ a/mm/memory_hotplug.c @@ -1209,6 +1209,13 @@ int online_pages(unsigned long pfn, unsi if (node_arg.nid >= 0) node_set_state(nid, N_MEMORY); + /* + * Check whether we are adding normal memory to the node for the first + * time. + */ + if (!node_state(nid, N_NORMAL_MEMORY) && zone_idx(zone) <= ZONE_NORMAL) + node_set_state(nid, N_NORMAL_MEMORY); + if (need_zonelists_rebuild) build_all_zonelists(NULL); @@ -1908,6 +1915,8 @@ int offline_pages(unsigned long start_pf unsigned long flags; char *reason; int ret; + unsigned long normal_pages = 0; + enum zone_type zt; /* * {on,off}lining is constrained to full memory sections (or more @@ -2056,6 +2065,17 @@ int offline_pages(unsigned long start_pf init_per_zone_wmark_min(); /* + * Check whether this operation removes the last normal memory from + * the node. We do this before clearing N_MEMORY to avoid the possible + * transient "!N_MEMORY && N_NORMAL_MEMORY" state. + */ + if (zone_idx(zone) <= ZONE_NORMAL) { + for (zt = 0; zt <= ZONE_NORMAL; zt++) + normal_pages += pgdat->node_zones[zt].present_pages; + if (!normal_pages) + node_clear_state(node, N_NORMAL_MEMORY); + } + /* * Make sure to mark the node as memory-less before rebuilding the zone * list. Otherwise this node would still appear in the fallback lists. */ _ Patches currently in -mm which might be from hao.li@linux.dev are