From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-142.mta0.migadu.com [91.218.175.142]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 917EB446C0C for ; Tue, 15 Sep 2026 06:59:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.142 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789455579; cv=none; b=ZfD2/FkhlMoOoSBRyUR8TsQul3Dh2ISeT4slLcf9uE9fDREFPUNvYdwli30YBBmi4KYPFF8Dcw8y/1s9eZngBZcId2rgzVddRL2PYw/Oi/jG89eLYFHeIsx9ZlkP8V9MyelSHD5wNGbHCm/JsTMW1SnDXkd19jvtuyLuG/Dwr7w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789455579; c=relaxed/simple; bh=j1q5lh6+pcNupQnOWdCoKiNEOrdrCXWiA588ffNXkqk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ls3L3FiRfu5H1kh1Bi7x+Mp+eB3J9GSx0INnv7oR0TjaVfuxMowy8OfhkemiG5RmzelStxAZH81olV3XIPrZxr92/TibygyhU8A3dW4F3dfMH73TUkNYnF01Z0KLYJtjj3aAqTg9PAE7gjvfJUqo2EQRyQO9l5wEmfzwxEHTI9M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=kcwewssJ; arc=none smtp.client-ip=91.218.175.142 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="kcwewssJ" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=j1q5lh6+pcNupQnOWdCoKiNEOrdrCXWiA588ffNXkqk=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1789455575; v=1; x=1790060375; b=kcwewssJoV9tjMvq8zA7F36JiK8XsZIx99HA4Hi5iMdA43G12vyPbV1ZVYHEEokVJwK7u2Rt ei+2BuSYhJdWwYhFP5Oxwg9tn2YuBTTaZ2w4Yta/OFq6ZPIylRd1vQVCI5BoSZuQ4uX4l/Q+AS1 OII+G2A3x2Iw5fyISiEg6HpM= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 245cf166983b45cf; Tue, 15 Sep 2026 06:59:35 +0000 X-Mizu-Trace-ID: 245cf166983b45cf X-Migadu-Flow: FLOW_OUT From: Hao Ge To: Luis Chamberlain , Petr Pavlu , Daniel Gomez , Sami Tolvanen , Aaron Tomlin , Suren Baghdasaryan , Kent Overstreet , Hao Ge , Andrew Morton Cc: linux-modules@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Sashiko , stable@vger.kernel.org Subject: [PATCH v10 5/6] alloc_tag: skip percpu counter allocation when profiling is disabled Date: Tue, 15 Sep 2026 15:00:00 +0800 Message-Id: <20260915070001.113559-6-hao.ge@linux.dev> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260915070001.113559-1-hao.ge@linux.dev> References: <20260915070001.113559-1-hao.ge@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit After shutdown_mem_profiling() clears mem_profiling_support, needs_section_mem() returns false, so later modules have their codetag section placed as regular data and never enter the alloc_tag maple tree. codetag_load_module() still called load_module(), which allocated a percpu counter for every tag; release_module_tags() could not find these modules on unload, so the counters leaked. Return -EOPNOTSUPP from load_module() when profiling is off: codetag_module_init() drops the module's cmod, no counters are allocated and the module loads without its tags. codetag_unload_module() now always calls free_section_mem(), since a module whose module_load() returned -EOPNOTSUPP is not in the idr but may still hold a reserved section. Reported-by: Sashiko Fixes: 4835f747d3ed ("alloc_tag: support for page allocation tag compression") Cc: stable@vger.kernel.org Suggested-by: Suren Baghdasaryan Acked-by: Suren Baghdasaryan Signed-off-by: Hao Ge --- lib/codetag.c | 10 ++++++++-- mm/alloc_tag.c | 4 ++++ 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/lib/codetag.c b/lib/codetag.c index a9cda4c962a3..a0b600720afc 100644 --- a/lib/codetag.c +++ b/lib/codetag.c @@ -240,7 +240,9 @@ static int codetag_module_init(struct codetag_type *cttype, struct module *mod) if (err < 0) { kfree(cmod); - return err; + /* -EOPNOTSUPP means we can load the module without its tag. */ + if (err != -EOPNOTSUPP) + return err; } return 0; @@ -388,7 +390,11 @@ void codetag_unload_module(struct module *mod) ++cttype->content_id; } up_write(&cttype->mod_lock); - if (found && cttype->desc.free_section_mem) + /* + * A module whose module_load() returned -EOPNOTSUPP is not + * in the idr but may still hold reserved section memory. + */ + if (cttype->desc.free_section_mem) cttype->desc.free_section_mem(mod, true); } mutex_unlock(&codetag_lock); diff --git a/mm/alloc_tag.c b/mm/alloc_tag.c index 5836803898ad..1ca0409b492b 100644 --- a/mm/alloc_tag.c +++ b/mm/alloc_tag.c @@ -988,6 +988,10 @@ static int load_module(struct module *mod, struct codetag *start, struct codetag struct alloc_tag *stop_tag; struct alloc_tag *tag; + /* Profiling disabled: load the module without its tags. */ + if (!mem_profiling_support) + return -EOPNOTSUPP; + /* percpu counters for core allocations are already statically allocated */ if (!mod) return 0; -- 2.25.1