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received-spf: None (protection.outlook.com: microsoft.com does not designate permitted sender hosts) authentication-results: spf=none (sender IP is ) smtp.mailfrom=Alexander.Levin@microsoft.com; x-microsoft-antispam-message-info: EqT8I1Xy+YZYij55Z+fXVxXlxA6CugUwj4FM7g+iA5+3YIumUfHQjg7jhJFXJMWosBNhuY6Y/7cQ+CGeWKkUNAE62gbwQiRCb/3rzdJpwt4SCCn2LKGTB6cdjC3iJf1HOSlwvIWwf3tfmGFa24thxm+8hJXB5q83xY+GsdrJpvnL8K4UE8oifdfuQ2kq21BjPC1U0FQmjNLWgz3NjHKAYIU0JR6/zdDpkzngtLeTtoYDUs8lbmPEDIKDCwJuUo5DHCrNXze2ktkqqUukGJSnVxCjewXKBMb6eUcCk/b5CN0sG0mwE9cNFT/Hp5B1q8+Bt8W/PAZTv7HvD9QBqQebl1FuaTO6wErWzlfBg22ZEO8= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3c8a597d-cf87-4492-6893-08d624b2bb4f X-MS-Exchange-CrossTenant-originalarrivaltime: 27 Sep 2018 19:52:18.3815 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR21MB0630 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 17, 2018 at 08:50:27AM -0300, Ezequiel Garcia wrote: >Hi Sasha, > >On Mon, 2018-09-17 at 03:03 +0000, Sasha Levin wrote: >> From: Ezequiel Garcia >> >> [ Upstream commit cd63c0288fd760ce7de247fba618e2bbcfc0c35c ] >> >> Currently, this driver does not serialize its video4linux >> ioctls, which is a bug, as race conditions might appear. >> >> In addition, video_device and vb2_queue locks are now both >> mandatory. Add them, and implement wait_prepare and >> wait_finish. >> >> To stay on the safe side, this commit uses a single mutex >> for both locks. Better latency can be obtained by separating >> these if needed. >> >> Signed-off-by: Ezequiel Garcia >> Signed-off-by: Hans Verkuil >> Signed-off-by: Mauro Carvalho Chehab >> Signed-off-by: Sasha Levin > >Hm, I am not so sure this patch should go to -stable, >as it's not fixing a real bug we've seen out there. You don't really need to wait for a report of this happening if you're certain that this can happen in the "real world". Having a report is not a prerequisite of inclusion in stable. However, if you prefer not to, I can just remove it.=