From nobody Thu Oct 2 03:27:35 2025 Received: from cstnet.cn (smtp84.cstnet.cn [159.226.251.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5248013777E; Mon, 29 Sep 2025 01:30:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759109439; cv=none; b=pKVRPPPFtnNGrmdBCtDtdRw3fw9yJtu1DGTXKE+Ow7l6q94+R3kITLcpqUmwgIO1/l1KjQia6V11DoKPS/2Y54RbauwYhdcFurSau1KP5D5TJwLK4wzXIkzVDja3VLx7zWNMPmQCt58ljd5cOz7RWRq5dj2/OCu6Kq8RszMFId4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759109439; c=relaxed/simple; bh=jgYfnGlpJUsBLnIp0dgG9Um0H/BiAyG/N/ufXTWeP7g=; h=From:To:Cc:Subject:Date:Message-Id; b=Tuna/Fz8wTFMWXE+KpZzKYNy4oxjDBs2Arf3sY0LEDNLBVtNhe56oLXt56peyDNuWr1snK6r+FCJPJIwa2qduV0obBKlRsFvbFeb0kqmW3UADxvIIKyKu79kdBnl//qfO/xL1LHF8IjtqVG8e3+zG9eqg8ubfX3GDd/3K/oPftY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [202.112.113.212]) by APP-05 (Coremail) with SMTP id zQCowADHaRMg4dloIUR_CA--.42010S2; Mon, 29 Sep 2025 09:30:19 +0800 (CST) From: Ma Ke To: sakari.ailus@linux.intel.com, bingbu.cao@intel.com, lixu.zhang@intel.com, stanislaw.gruszka@linux.intel.com, mchehab@kernel.org, wentong.wu@intel.com Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Ma Ke Subject: [PATCH v5] media: pci: intel: ivsc: improve device reference counting in mei_ace driver Date: Mon, 29 Sep 2025 09:30:07 +0800 Message-Id: <20250929013007.1920-1-make24@iscas.ac.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: zQCowADHaRMg4dloIUR_CA--.42010S2 X-Coremail-Antispam: 1UD129KBjvJXoW7WFWfWrWDAr1kCryDtF1fWFg_yoW8CF1kpr Wq9FWkKFWUXr4jgr1UAa18ZFyrWa1Sya9xGr43Aa1xu3W5Z347try0qa47Ca4YqFZrCFy7 AF13KryfAF40yw7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUP014x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gr 1j6F4UJwAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40E FcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr 0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8v x2IErcIFxwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCY02Avz4 vE14v_KwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Jr0_Gr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r 4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Jr0_GrUvcSsGvfC2KfnxnUUI43ZEXa7VUb9mitUU UUU== X-CM-SenderInfo: ppdnvj2u6l2u1dvotugofq/ Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The device reference counting in mei_ace_setup_dev_link() was incomplete, as the reference acquired by device_find_child_by_name() was not released immediately on the success path. Add put_device() to properly balance the reference count. Additionally, the redundant put_device() in mei_ace_remove() is removed. Found by code review. Signed-off-by: Ma Ke --- Changes in v5: - jumped to err instead of err_put to avoid calling put_device() again in e= rr_put as reviewer's instructions; Changes in v4: - updated the subject as suggestions; Changes in v3: - deleted the tag of Fixes and CC, and moved put_device() to immediately af= ter device_link_add() as suggestions; Changes in v2: - modified the put_device() operations and the patch title as suggestions. --- drivers/media/pci/intel/ivsc/mei_ace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/pci/intel/ivsc/mei_ace.c b/drivers/media/pci/int= el/ivsc/mei_ace.c index 98310b8511b1..b306a320b70f 100644 --- a/drivers/media/pci/intel/ivsc/mei_ace.c +++ b/drivers/media/pci/intel/ivsc/mei_ace.c @@ -414,10 +414,11 @@ static int mei_ace_setup_dev_link(struct mei_ace *ace) /* setup link between mei_ace and mei_csi */ ace->csi_link =3D device_link_add(csi_dev, dev, DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE | DL_FLAG_STATELESS); + put_device(csi_dev); if (!ace->csi_link) { ret =3D -EINVAL; dev_err(dev, "failed to link to %s\n", dev_name(csi_dev)); - goto err_put; + goto err; } =20 ace->csi_dev =3D csi_dev; @@ -522,7 +523,6 @@ static void mei_ace_remove(struct mei_cl_device *cldev) cancel_work_sync(&ace->work); =20 device_link_del(ace->csi_link); - put_device(ace->csi_dev); =20 pm_runtime_disable(&cldev->dev); pm_runtime_set_suspended(&cldev->dev); --=20 2.17.1