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Darwish" CC: Peter Xu , , Linus Torvalds , Andrea Arcangeli , Andrew Morton , Aneesh Kumar K.V , Christoph Hellwig , Hugh Dickins , Jan Kara , Jann Horn , John Hubbard , Kirill Shutemov , Kirill Tkhai , Leon Romanovsky , Linux-MM , Michal Hocko , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Will Deacon , Thomas Gleixner , Sebastian Siewior Subject: Re: [PATCH v2 2/2] mm: prevent gup_fast from racing with COW during fork Message-ID: <20201103002532.GL2620339@nvidia.com> References: <0-v2-dfe9ecdb6c74+2066-gup_fork_jgg@nvidia.com> <2-v2-dfe9ecdb6c74+2066-gup_fork_jgg@nvidia.com> <20201030225250.GB6357@xz-x1> <20201030235121.GQ2620339@nvidia.com> <20201103001712.GB52235@lx-t490> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20201103001712.GB52235@lx-t490> X-ClientProxiedBy: MN2PR11CA0026.namprd11.prod.outlook.com (2603:10b6:208:23b::31) To DM6PR12MB3834.namprd12.prod.outlook.com (2603:10b6:5:14a::12) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from mlx.ziepe.ca (156.34.48.30) by MN2PR11CA0026.namprd11.prod.outlook.com (2603:10b6:208:23b::31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3499.27 via Frontend Transport; Tue, 3 Nov 2020 00:25:33 +0000 Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1kZk8i-00Fil0-7b; Mon, 02 Nov 2020 20:25:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1604363139; bh=PcebY4tfQL3perSWSe4y29QCoLKdGs7bYoQZgZFL/wI=; h=ARC-Seal:ARC-Message-Signature:ARC-Authentication-Results:Date: From:To:CC:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:X-ClientProxiedBy:MIME-Version: X-MS-Exchange-MessageSentRepresentingType; b=GYNeJyKQtP05zeNRfQgp+d4pUlZrUHuE35LdpEornY6fw9PkBAoq6vb3Lb1TEwZ/e 4363Xd+idn2soHKH2ukOIkZ3NuONkaAaUSomTB7msrnbhnOjqEMWhrvzFKx3Iaee0l gS+zwrUHXPQdaM6uZdG4QpSxBr86HvnY9kqXCl6Irt15iFTRZ7tMTNygY8Ln/dg9HP J4GpeWCTtWGpN/v6FIL3g08NdbAe9uyzHorNKKgUWbSnjvtFWxXbOgcjk7CN/wBpbp GP28hyN8/gYoZBda0E4igcRwpepZ2BorPS06bOHQWJJolp7s1vXbhulduOt9ShxvnH NaWtmdTe44UGw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Nov 03, 2020 at 01:17:12AM +0100, Ahmed S. Darwish wrote: > Please stick with the official exported API: raw_write_seqcount_begin(). How did you know this was 'offical exported API' ?? > Exactly. '*_seqcount_t_*' is a seqlock.h implementation detail, and it > has _zero_ relevance to what is discussed in this thread actually. Add some leading __'s to them? Jason