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 DCFBF1684BE for ; Tue, 24 Mar 2026 23:16:13 +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=1774394173; cv=none; b=txlzRV5aCp0hjz62Dt4qXVJcEpQlxI1W0Mrm8aDCNtxdUzxRFg0S3sboDRZpcQdV+bs1kXrl3LK47QCnvkFO+5F/vMwxOPAexNE4p4cDAfH5hipQhvHyOZhA9t6mQT01E41tWwRuMiMLfR3UUI+grGFPqn4fQcQt6UJkdDJStGA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774394173; c=relaxed/simple; bh=oEDra/0g8/JR9FNoByAjU/kc1wRLOftf5KJJYdriGQ8=; h=Date:To:From:Subject:Message-Id; b=S2685MleWpqYARROgNAI6NG85wu5yGCK/4H0wA2jjkxQHqzLT8aGJGAcDXx+SIluuGybzy8f2VCdQiTbpt2a4X3iEJx/JaSLd2YTzWhjIEZOEqBmcbrGMoo4YuVCUrrmC5t/XOqXfbnnuAiRZ5D+dCMmoETICADroTtOutZwK4M= 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=BpDw2saQ; 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="BpDw2saQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84FC0C19424; Tue, 24 Mar 2026 23:16:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1774394173; bh=oEDra/0g8/JR9FNoByAjU/kc1wRLOftf5KJJYdriGQ8=; h=Date:To:From:Subject:From; b=BpDw2saQUXPFZrna7BoROdMTyeol48t/HzHjU88u8lAfxDjHG3SNBCqQFMXcHPEV5 rgwCqSSPwaQ8b+LXylGllvTwsNCBbyn/OF6aT+mtRDBNROqfEywCFpjR1jL3r3WydY vEFQZIlWvp8CI/y1nU4LrH+8YJRKerwl2amk5+Ag= Date: Tue, 24 Mar 2026 16:16:13 -0700 To: mm-commits@vger.kernel.org,zhengqi.arch@bytedance.com,shakeel.butt@linux.dev,roman.gushchin@linux.dev,muchun.song@linux.dev,mhocko@kernel.org,hannes@cmpxchg.org,devnexen@gmail.com,akpm@linux-foundation.org From: Andrew Morton Subject: [folded-merged] mm-memcontrol-convert-objcg-to-be-per-memcg-per-node-type-fix-fix-fix-2.patch removed from -mm tree Message-Id: <20260324231613.84FC0C19424@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/memcontrol: fix obj_cgroup leak in mem_cgroup_css_online() error path has been removed from the -mm tree. Its filename was mm-memcontrol-convert-objcg-to-be-per-memcg-per-node-type-fix-fix-fix-2.patch This patch was dropped because it was folded into mm-memcontrol-convert-objcg-to-be-per-memcg-per-node-type.patch ------------------------------------------------------ From: David Carlier Subject: mm/memcontrol: fix obj_cgroup leak in mem_cgroup_css_online() error path Date: Sun, 22 Mar 2026 19:36:31 +0000 When obj_cgroup_alloc() fails partway through the NUMA node loop in mem_cgroup_css_online(), the free_objcg error path drops the extra reference held by pn->orig_objcg but never kills the initial percpu_ref from obj_cgroup_alloc() stored in pn->objcg. Since css_offline is never called when css_online fails, memcg_reparent_objcgs() never runs, so the percpu_ref_kill() that normally drops this initial reference never executes. The obj_cgroup and its per-cpu ref allocations are leaked. Clear pn->objcg via rcu_replace_pointer() and add the missing percpu_ref_kill() in the error path, matching the normal teardown sequence in memcg_reparent_objcgs(). Also add a NULL check for pn in __mem_cgroup_free() to prevent a NULL pointer dereference when alloc_mem_cgroup_per_node_info() fails partway through the node loop in mem_cgroup_alloc(). Link: https://lkml.kernel.org/r/20260322193631.45457-1-devnexen@gmail.com Signed-off-by: David Carlier Acked-by: Qi Zheng Cc: Johannes Weiner Cc: Michal Hocko Cc: Muchun Song Cc: Roman Gushchin Cc: Shakeel Butt Signed-off-by: Andrew Morton --- mm/memcontrol.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/mm/memcontrol.c~mm-memcontrol-convert-objcg-to-be-per-memcg-per-node-type-fix-fix-fix-2 +++ a/mm/memcontrol.c @@ -3854,6 +3854,8 @@ static void __mem_cgroup_free(struct mem for_each_node(node) { struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; + if (!pn) + continue; obj_cgroup_put(pn->orig_objcg); free_mem_cgroup_per_node_info(pn); @@ -4055,8 +4057,11 @@ static int mem_cgroup_css_online(struct free_objcg: for_each_node(nid) { struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; + objcg = rcu_replace_pointer(pn->objcg, NULL, true); + if (objcg) + percpu_ref_kill(&objcg->refcnt); - if (pn && pn->orig_objcg) { + if (pn->orig_objcg) { obj_cgroup_put(pn->orig_objcg); /* * Reset pn->orig_objcg to NULL to prevent _ Patches currently in -mm which might be from devnexen@gmail.com are mm-hugetlb-restore-reservation-on-error-in-hugetlb_mfill_atomic_pte-resubmission-path.patch mm-memcontrol-convert-objcg-to-be-per-memcg-per-node-type.patch mm-memcontrol-convert-objcg-to-be-per-memcg-per-node-type-fix-fix-fix-2-fix.patch mm-page_io-fix-pswpin-undercount-for-large-folios-in-sio_read_complete.patch