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=-5.8 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 D8C7BC4332B for ; Wed, 17 Mar 2021 08:05:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42DF164F7F for ; Wed, 17 Mar 2021 08:05:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230064AbhCQIFU (ORCPT ); Wed, 17 Mar 2021 04:05:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230196AbhCQIFC (ORCPT ); Wed, 17 Mar 2021 04:05:02 -0400 Received: from mail-oi1-x230.google.com (mail-oi1-x230.google.com [IPv6:2607:f8b0:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E083C061762 for ; Wed, 17 Mar 2021 01:05:02 -0700 (PDT) Received: by mail-oi1-x230.google.com with SMTP id x78so40966442oix.1 for ; Wed, 17 Mar 2021 01:05:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=EI5qglqxsKAU/W0ZKYTsFSvZf8l0B/oXcoORkaxMSD8=; b=fb1VA654QtgBN7yjx24Vbsgr8qILHcsfU8IERmXJmGaXai7ib/t/sz/A2+trz33o9V +jZ2x+KTzIoXu9ur15pcoOP0mcety3wwVzOYYhW2IDGTduuc/R5KdINLJaadqXnV3Anw TPbRuol5s8uvpHLE2zkBMQ0iFY8Iob2xpapBI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=EI5qglqxsKAU/W0ZKYTsFSvZf8l0B/oXcoORkaxMSD8=; b=LXQMeMMKuIegoJAKc56ejWgA5V6tCREjFi9c8/qc8Ma3RDSd23mH6us9/Bc9MECO7Y 9iDZdscTdOPHVvYIygFgnpVlRTi/Dax6OroS9+G075h1NRT11l4Rtei3AAtr5exFbA7C HCatDRUvk2mK5mLjBrsf+Vm7BT2pWxBueYzRDPiVy4cS6gXp4WWsJ3GmuLqVTtLIC5M7 U3OsuDIh28KjdyldTvw2QYeQ9488n1RCZKJ8lRG8hUIjbg9nXqlMH9bTH5K1akHOOkxt lhEg1ozBvJ/VeoZ8npZbEdETVWCPG2/lZvCsX4WsNiYm0RSg32juErMJEsqHtdPlNen0 SNLQ== X-Gm-Message-State: AOAM531P1oQWCMcdZMBGIbYHkef9s7o+znnNOGVOcN1RdKl5ujaia1O5 A1s2vywYUqOcjm5wCDRQjzl6ChY09VTF+mm0j6kpXQ== X-Google-Smtp-Source: ABdhPJwZYNnRwoTd/kuED1Yfh8EqOUzOIuqMpTc+matmHqjzLk6Tn4x3yBWT0QFOmmnBuxIzgcZ9JwEdKsAutEEaYeo= X-Received: by 2002:aca:4188:: with SMTP id o130mr1878713oia.101.1615968301447; Wed, 17 Mar 2021 01:05:01 -0700 (PDT) MIME-Version: 1.0 References: <20210316153303.3216674-1-daniel.vetter@ffwll.ch> <20210316153303.3216674-3-daniel.vetter@ffwll.ch> <20210316154549.GA60450@infradead.org> <20210317072248.GA284559@infradead.org> In-Reply-To: <20210317072248.GA284559@infradead.org> From: Daniel Vetter Date: Wed, 17 Mar 2021 09:04:50 +0100 Message-ID: Subject: Re: [PATCH 2/3] media/videobuf1|2: Mark follow_pfn usage as unsafe To: Christoph Hellwig Cc: DRI Development , LKML , KVM list , Linux MM , Linux ARM , linux-samsung-soc , "open list:DMA BUFFER SHARING FRAMEWORK" , Tomasz Figa , Hans Verkuil , Daniel Vetter , Jason Gunthorpe , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , "J??r??me Glisse" , Jan Kara , Pawel Osciak , Marek Szyprowski , Kyungmin Park , Laurent Dufour , Vlastimil Babka , Daniel Jordan , Michel Lespinasse Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Wed, Mar 17, 2021 at 8:22 AM Christoph Hellwig wrote: > On Tue, Mar 16, 2021 at 04:52:44PM +0100, Daniel Vetter wrote: > > My understanding is mostly, but with some objections. And I kinda > > don't want to let this die in a bikeshed and then not getting rid of > > follow_pfn as a result. There's enough people who acked this, and the > > full removal got some nack from Mauro iirc. > > Hmm, ok I must have missed that. I defintively prefer your series over > doing nothing, but killing the dead horse ASAP would be even better. I have a bunch of slow-burner things I need to fix in this area of driver mmaps vs get_user_/follow_ conflicts anyway, I'll add a note to put the horse out of it's misery in due time. We have a few problems still where things might get pinned or used where it really shouldn't be. Can I count that as an ack on the series? You've touched this quite a bit recently. Thanks, Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch