From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E202C55178 for ; Mon, 2 Nov 2020 17:16:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB2FE21D91 for ; Mon, 2 Nov 2020 17:16:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="OzpU9SvL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727779AbgKBRQn (ORCPT ); Mon, 2 Nov 2020 12:16:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727388AbgKBRQm (ORCPT ); Mon, 2 Nov 2020 12:16:42 -0500 Received: from mail-qk1-x741.google.com (mail-qk1-x741.google.com [IPv6:2607:f8b0:4864:20::741]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C866C061A48 for ; Mon, 2 Nov 2020 09:16:41 -0800 (PST) Received: by mail-qk1-x741.google.com with SMTP id r7so12162730qkf.3 for ; Mon, 02 Nov 2020 09:16:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=nOooqOL2HAfCzA3WbZS617x/HCXK3f8ujSR4To+U+xs=; b=OzpU9SvL4LQMiSZU+/wC8SOY7Kd5nwVlGSTQjG9d88TeMJ4WpFyipjmaUdp1TxOYVn 7vidwyiSRCZj33RSLCqu0pXEDxMU/dAAoukKMfQfZuIAjtLdwwP4N2zY3W8B92Z6AwFE OTED+BMjliDXrbRWrDsPovc1pCXjBe20TOvquBC1aoMM7tLd9pJLJZOtf/olLrbdulv4 wmYRU9+3HhHbwX4F5ELPi2SPcx5nfQMbB/P20GVamTcL6w1vdCvhRKxx/L/E22ILoMnS rmp9SSiTbFRAYQDj9HHFQ8bEOTeAHdVsxV9Tfe2mGZkEyeAYsnLrRuqy6EC2kl3h/BMa 5ZGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=nOooqOL2HAfCzA3WbZS617x/HCXK3f8ujSR4To+U+xs=; b=kPylm/nssAmagmJg6LAcWcBF7NyLozKq+8oeLdrePDC8lL9s28yaLTYQGUSsP5rbF4 Colep2Tf1f9Fla+Nl8l07+Greqq07pHBPYjtbIT8ZJETpd45wKojISo3CcGmGX2tISU3 FygV0mSYYu3qfpEzq+yxYnz8afe6BFzplpDaCAbV9DlEOoiuhHuYlAGccwqQ4bjbp3zy JIZtupRPO6GQsUgd47u7wGLbIFwLSVJWEum7sVHwfMFQi+b+qqy7w3kIMrY2BwY/4Or4 nsPyf7l1dtgvXgG+qKe5S27U1OS3hR2CYy+DwwmJmCkDnEIU4IJ6VwpKeZRE4eoPXO0l 81xw== X-Gm-Message-State: AOAM532KLqYH5OCJ/UdeHcV5KVHmHvP7LRtKYKnRuHAxOgsarkdb+dad zu2SymBUjpgtOv0DoYJVtCaFAw== X-Google-Smtp-Source: ABdhPJzKAXEdRCm0W3ToJIDRDSewKlEjp6I2L8WD4tRBCiFlVxj0ALakWiSn3a8Exau8avpdo4ShfA== X-Received: by 2002:a37:f503:: with SMTP id l3mr6457698qkk.160.1604337400730; Mon, 02 Nov 2020 09:16:40 -0800 (PST) Received: from ziepe.ca (hlfxns017vw-156-34-48-30.dhcp-dynamic.fibreop.ns.bellaliant.net. [156.34.48.30]) by smtp.gmail.com with ESMTPSA id c76sm8677260qkb.20.2020.11.02.09.16.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 02 Nov 2020 09:16:40 -0800 (PST) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1kZdRf-00FI9F-Az; Mon, 02 Nov 2020 13:16:39 -0400 Date: Mon, 2 Nov 2020 13:16:39 -0400 From: Jason Gunthorpe To: Daniel Vetter Cc: Christoph Hellwig , DRI Development , LKML , KVM list , Linux MM , Linux ARM , linux-samsung-soc , "open list:DMA BUFFER SHARING FRAMEWORK" , Daniel Vetter , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , J??r??me Glisse , Jan Kara Subject: Re: [PATCH v5 08/15] mm: Add unsafe_follow_pfn Message-ID: <20201102171639.GH36674@ziepe.ca> References: <20201030100815.2269-1-daniel.vetter@ffwll.ch> <20201030100815.2269-9-daniel.vetter@ffwll.ch> <20201102072931.GA16419@infradead.org> <20201102130115.GC36674@ziepe.ca> <20201102155256.GG36674@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org On Mon, Nov 02, 2020 at 05:42:20PM +0100, Daniel Vetter wrote: > > Need to hold the lock to check that and there are two ways to register > > notifiers these days, so it feels to expensive to me. > > Uh I mixed stuff up all along, struct mmu_notifier *subcription that > all the mmu notifier users use has the ->mm pointer we want right > there. That's good enough I think. Yah, if you can pass in one of those instead of the raw mm it would be fine Jason