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=-3.8 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,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 9103DC56202 for ; Thu, 22 Oct 2020 13:04:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3B2324171 for ; Thu, 22 Oct 2020 13:04:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="hFupg462" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2899254AbgJVNE2 (ORCPT ); Thu, 22 Oct 2020 09:04:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2899241AbgJVNE1 (ORCPT ); Thu, 22 Oct 2020 09:04:27 -0400 Received: from mail-ot1-x343.google.com (mail-ot1-x343.google.com [IPv6:2607:f8b0:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DA45C0613CF for ; Thu, 22 Oct 2020 06:04:26 -0700 (PDT) Received: by mail-ot1-x343.google.com with SMTP id n11so1409892ota.2 for ; Thu, 22 Oct 2020 06:04:26 -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=ZyNrxU7+apn6xOGNK6avkKI1+/ers9vOGia4XvYK0qo=; b=hFupg462AQWF/3SYEGt7TdCBz7vmVV24cGf5H3PsZJ3NHOF7ARTtk1Xj9pQ6xHZuZX osgTY+1RlCMoExun5CEMIKW0/Q22JFrGKszrr35SoM6z+n1XQ4DOZb0ztKWF8FqsQ0rj YYO9Ror43OTX+8WLAdJnTsM4HmBRXtLFYIBBA= 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=ZyNrxU7+apn6xOGNK6avkKI1+/ers9vOGia4XvYK0qo=; b=dR9K5PUve3emtFqZXgpfC8vfgrcC3EpAiQ67Pj8dGcXB49Ns1No1IAuGo4ZxiNOLC9 noCPfKgUYk3fXNOuieuxbSnZ7DruHv7B7bBL0tAVNj0P3nXjcSFTeMfBeDCh5G4mTDun ua9vJ7Nj9F6gEP+DytfI/XLRs6sOxSknhyeOuArJUKavn2J7+GojPImuKVKYR7IDkJKs KNpMo/LkJZB0dbX/mSPeZU3SrzxCJ0iTUQEo4aZLcOobqpn8xNDFjcnrplnCkhzbrBTF sKLRXIx5E2yKvwd/UdAtlMkDSL6yXcLpd0Sf5HpvLNSH+utYRn0AB0k1oBpHSl15wEsB NYqQ== X-Gm-Message-State: AOAM530uCqeT/d52V83PVYmU00Gkv1NlJ6LEsyONUExFpixI0SogCQ8i Zy2es3EOVZbinWK5HQQB1aRjl/SMF7chwdeFkatn9Q== X-Google-Smtp-Source: ABdhPJx8bjchuHtk5X5j8AOy5uSsJ+M716njPCO+bint+3P1gD9xIsXgxoepgb7cnqWbI4FroPmfqz6vrX/g4fdQHsY= X-Received: by 2002:a05:6830:1647:: with SMTP id h7mr1916643otr.281.1603371865933; Thu, 22 Oct 2020 06:04:25 -0700 (PDT) MIME-Version: 1.0 References: <20201021085655.1192025-1-daniel.vetter@ffwll.ch> <20201021085655.1192025-13-daniel.vetter@ffwll.ch> <20201021125030.GK36674@ziepe.ca> <20201021151352.GL36674@ziepe.ca> <20201021163702.GM36674@ziepe.ca> <20201021232022.GN36674@ziepe.ca> <20201022114345.GO36674@ziepe.ca> In-Reply-To: <20201022114345.GO36674@ziepe.ca> From: Daniel Vetter Date: Thu, 22 Oct 2020 15:04:14 +0200 Message-ID: Subject: Re: [PATCH v3 12/16] PCI: Obey iomem restrictions for procfs mmap To: Jason Gunthorpe Cc: DRI Development , LKML , KVM list , Linux MM , Linux ARM , linux-samsung-soc , "open list:DMA BUFFER SHARING FRAMEWORK" , linux-s390 , Daniel Vetter , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Bjorn Helgaas , Linux PCI , Daniel Vetter Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 22, 2020 at 1:43 PM Jason Gunthorpe wrote: > > On Thu, Oct 22, 2020 at 09:00:44AM +0200, Daniel Vetter wrote: > > On Thu, Oct 22, 2020 at 1:20 AM Jason Gunthorpe wrote: > > > > > > On Wed, Oct 21, 2020 at 09:24:08PM +0200, Daniel Vetter wrote: > > > > On Wed, Oct 21, 2020 at 6:37 PM Jason Gunthorpe wrote: > > > > > > > > > > On Wed, Oct 21, 2020 at 05:54:54PM +0200, Daniel Vetter wrote: > > > > > > > > > > > The trouble is that io_remap_pfn adjust vma->pgoff, so we'd need to > > > > > > split that. So ideally ->mmap would never set up any ptes. > > > > > > > > > > /dev/mem makes pgoff == pfn so it doesn't get changed by remap. > > > > > > > > > > pgoff doesn't get touched for MAP_SHARED either, so there are other > > > > > users that could work like this - eg anyone mmaping IO memory is > > > > > probably OK. > > > > > > > > I was more generally thinking for io_remap_pfn_users because of the > > > > mkwrite use-case we might have in fbdev emulation in drm. > > > > > > You have a use case for MAP_PRIVATE and io_remap_pfn_range()?? > > > > Uh no :-) > > So it is fine, the pgoff mangling only happens for MAP_PRIVATE Ah right I got confused, thanks for clarifying. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch