Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Andy Duan <fugang.duan@nxp.com>
To:     David Miller <davem@davemloft.net>,
        "navid.emamdoost@gmail.com" <navid.emamdoost@gmail.com>
CC:     "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "emamd001@umn.edu" <emamd001@umn.edu>,
        "wu000273@umn.edu" <wu000273@umn.edu>,
        "kjlu@umn.edu" <kjlu@umn.edu>,
        "mccamant@cs.umn.edu" <mccamant@cs.umn.edu>
Subject: RE: [EXT] Re: [PATCH] net: fec: fix ref count leaking when
 pm_runtime_get_sync fails
Thread-Topic: [EXT] Re: [PATCH] net: fec: fix ref count leaking when
 pm_runtime_get_sync fails
Thread-Index: AQHWQ1V3+vVzwdRR0UC91oL2FbKQiKjafRmA
Date:   Tue, 16 Jun 2020 02:03:25 +0000
Message-ID: <AM6PR0402MB3607327188F1F9178A7E5BFBFF9D0@AM6PR0402MB3607.eurprd04.prod.outlook.com>
References: <20200614053801.94112-1-navid.emamdoost@gmail.com>
 <20200615.134216.1492983787088475104.davem@davemloft.net>
In-Reply-To: <20200615.134216.1492983787088475104.davem@davemloft.net>
Accept-Language: zh-CN, en-US
Content-Language: en-US
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: 2d597b26-cc42-4139-45f3-08d8119974da
X-MS-Exchange-CrossTenant-originalarrivaltime: 16 Jun 2020 02:03:26.0002
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: MFTm/1ua0Y7jEM5qvv4gk+2FWGqpwx6sYl9XUu2ehhJeRJ4Xm6ZMSHh4pJsrLuiIVHMnrocENEU0YRGmWKR2qA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM6PR0402MB3430
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

From: David Miller <davem@davemloft.net> Sent: Tuesday, June 16, 2020 4:42 =
AM
> From: Navid Emamdoost <navid.emamdoost@gmail.com>
> Date: Sun, 14 Jun 2020 00:38:01 -0500
>=20
> > in fec_enet_mdio_read, fec_enet_mdio_write, fec_enet_get_regs,
> > fec_enet_open and fec_drv_remove, pm_runtime_get_sync is called which
> > increments the counter even in case of failure, leading to incorrect
> > ref count. In case of failure, decrement the ref count before returning=
.
> >
> > Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
>=20
> This does not apply to the net tree.

Wolfram Sang wonder if such de-reference can be better handled by pm runtim=
e core code.
https://lkml.org/lkml/2020/6/14/76