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Fri, 9 Aug 2019 10:23:09 +0000 From: "Adamski, Krzysztof (Nokia - PL/Wroclaw)" To: Wolfram Sang CC: "linux-i2c@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" Subject: Re: [PATCH] i2c: rcar: avoid race when unregistering slave client Thread-Topic: [PATCH] i2c: rcar: avoid race when unregistering slave client Thread-Index: AQHVTiD44nw1Shk3f0CzUXyjDPevKqbynJQA Date: Fri, 9 Aug 2019 10:23:09 +0000 Message-ID: <20190809102300.GB25406@localhost.localdomain> References: <20190808193910.12365-1-wsa+renesas@sang-engineering.com> In-Reply-To: <20190808193910.12365-1-wsa+renesas@sang-engineering.com> Accept-Language: pl-PL, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: HE1PR0901CA0066.eurprd09.prod.outlook.com (2603:10a6:3:45::34) To DB7PR07MB6042.eurprd07.prod.outlook.com (2603:10a6:10:8e::23) authentication-results: spf=none (sender IP is ) smtp.mailfrom=krzysztof.adamski@nokia.com; x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [131.228.32.167] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 8003b088-abb7-4c9c-d764-08d71cb3933b x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600148)(711020)(4605104)(1401327)(4618075)(2017052603328)(7193020);SRVR:DB7PR07MB5466; 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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: nokia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8003b088-abb7-4c9c-d764-08d71cb3933b X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Aug 2019 10:23:09.2899 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 5d471751-9675-428d-917b-70f44f9630b0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: RnISUFmCm0cX0u7D+0tMSijLZLAmqY1eF1Bx7Mi+LBrEaVKjA2514CbvmsshKlwwsbFm764smaR4rYmlsr5yCJSdP3O/KSgPXkynBch2F7Q= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB7PR07MB5466 Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org On Thu, Aug 08, 2019 at 09:39:10PM +0200, Wolfram Sang wrote: >After we disabled interrupts, there might still be an active one >running. Sync before clearing the pointer to the slave device. > >Reported-by: Krzysztof Adamski >Signed-off-by: Wolfram Sang >--- > >Tested with a Lager board (Renesas R-Car H2) and no regressions found. I >tried to run into this race via stress-testing but failed. The race >window is tiny, but it is still there, so let's fix it. > > drivers/i2c/busses/i2c-rcar.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > Reviewed-by: Krzysztof Adamski