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=-6.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 5C49DC388F9 for ; Wed, 21 Oct 2020 18:21:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDBAD2245B for ; Wed, 21 Oct 2020 18:21:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=intel-com.20150623.gappssmtp.com header.i=@intel-com.20150623.gappssmtp.com header.b="aI4DCgQQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2504052AbgJUSVa (ORCPT ); Wed, 21 Oct 2020 14:21:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2504040AbgJUSV3 (ORCPT ); Wed, 21 Oct 2020 14:21:29 -0400 Received: from mail-ej1-x642.google.com (mail-ej1-x642.google.com [IPv6:2a00:1450:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46BE1C0613D2 for ; Wed, 21 Oct 2020 11:21:29 -0700 (PDT) Received: by mail-ej1-x642.google.com with SMTP id w27so705193ejb.3 for ; Wed, 21 Oct 2020 11:21:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=lBYBT2trM0zWLuScJPu/8MEsMxH22DaNGgcD4PxkzgM=; b=aI4DCgQQ2pNgP8FJefkPAHWyeYDZ6gBOdUW5ASwTjCdJPt6/F0D5IUw+ryIpjQNXm7 gK4+rVdRij2UezhsYNKjky15pbLyx71SXm/fZWi7e8Q4m+RVncNlw0/EQHwWG71kG1jW swatZpkYTu5yAZOXhuMbyP3n0EJyZ6Tj4Y/cuYa29u3olktUJdc4M4TJ2rd4I+0DOH8g zGBna8sz6bZsljPuc9avDUo1nfa6ddJFnaen4gYQFZ8z/YYqPo9kDiLM1CATyUVyGmG8 pnWq4b5N/m5mvr9ZCnxufY7oD2D56MpGg2WZMNT6wzDAol9vlUAst1BSJiogsIkNya2g yS+g== 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:content-transfer-encoding; bh=lBYBT2trM0zWLuScJPu/8MEsMxH22DaNGgcD4PxkzgM=; b=VUrbb1v+TaBpZ2V9CWWG5UMjW865f8AqkRYJVN9BUjwFD6QvDYuyUp+id7w7fBQgw0 DMA8Y1IK39hJQDT1V/2QEOEBWzFi/CHfITIfncePT4Ggq0sOKNi23jnendOIFxIIZY6q 0sYWwR4JQtRrmqe6EhDh7NKCzJidSVFHElwvzuaSXWhIY0of8qXD7kHq+Zf/0aRrX0sN RPz9pEEwG+IKE+DIR2A/TWRybtvjma6+9yHnQnvuCeZ8hAQ+J+o8ZjfNubAM5+/lxXI5 3xztN0mcV4246tQy8EP3Kcyzw3CJyS4Jqp32ZMdGiGwQBUAMEZFTsVmfxmvbJs+naHG0 7Dpw== X-Gm-Message-State: AOAM532E8Pz7ZlWQvEJR5AjW4wZoyjp429Rg+NeVZZQpaN3LKnoUos2r szWgwhgdZedy+MCC/YFLpzX9YMlqxBpVhumVuOALdA== X-Google-Smtp-Source: ABdhPJzA1jSls/Kx/Mwjc1+1+EpDhh/HoRUDuIKQ8K0ggJGziicPcEE6tEKertKBv/kwHwmxQELgJDflTG3MPc+CL3w= X-Received: by 2002:a17:906:c20f:: with SMTP id d15mr4627011ejz.341.1603304487981; Wed, 21 Oct 2020 11:21:27 -0700 (PDT) MIME-Version: 1.0 References: <20201021085655.1192025-1-daniel.vetter@ffwll.ch> <20201021085655.1192025-14-daniel.vetter@ffwll.ch> In-Reply-To: <20201021085655.1192025-14-daniel.vetter@ffwll.ch> From: Dan Williams Date: Wed, 21 Oct 2020 11:21:17 -0700 Message-ID: Subject: Re: [PATCH v3 13/16] /dev/mem: Only set filp->f_mapping To: Daniel Vetter Cc: DRI Development , LKML , KVM list , Linux MM , Linux ARM , linux-samsung-soc , "Linux-media@vger.kernel.org" , linux-s390 , Daniel Vetter , Jason Gunthorpe , Kees Cook , Andrew Morton , John Hubbard , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Daniel Vetter Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 21, 2020 at 1:57 AM Daniel Vetter wrot= e: > > When we care about pagecache maintenance, we need to make sure that > both f_mapping and i_mapping point at the right mapping. > > But for iomem mappings we only care about the virtual/pte side of > things, so f_mapping is enough. Also setting inode->i_mapping was > confusing me as a driver maintainer, since in e.g. drivers/gpu we > don't do that. Per Dan this seems to be copypasta from places which do > care about pagecache consistency, but not needed. Hence remove it for > slightly less confusion. > > Signed-off-by: Daniel Vetter > Cc: Jason Gunthorpe > Cc: Kees Cook > Cc: Dan Williams > Cc: Andrew Morton > Cc: John Hubbard > Cc: J=C3=A9r=C3=B4me Glisse > Cc: Jan Kara > Cc: Dan Williams Reviewed-by: Dan Williams