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,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 DAC94C388F9 for ; Wed, 4 Nov 2020 16:38:35 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 625B2206D9 for ; Wed, 4 Nov 2020 16:38:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="XgN2lvYK"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="SV1Q76qA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 625B2206D9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=fz/RmCRiDLgwevX4ci30lFWK4a7AeZC7KcFr1FE8qEg=; b=XgN2lvYKr+JVFF3i34R82vcSm dSk6vA6Sohrg/KGs6ktZXt1ITvvjCn9KTpm5dSXcPogO97QM3AICyEtc+PQWRifZ7Q1xPoL3RhOMK UmuZ9fgxkr1J6O3FIdPhpkwExMqE6PHueuMzlLV2vc85fPlYugqnT9bjwGh76hqeFTH3aknNm55d9 c3/635gY9Jt4JjOd5OfWcss76pqS5IP183DpZZeTfiNfMG8byelCYYZvIPli5736tWRlDqjhbVGpL VKBDQ9LgwiWMjh3iR82fOGfRVnBN0s3D37b5+tNpOKE1sgBPx/UBgN6XBZZZMb0Xg4bWULtTWyr+L rZTwVp65w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaLnQ-0005F0-4m; Wed, 04 Nov 2020 16:38:04 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaLnO-0005EU-4X for linux-arm-kernel@merlin.infradead.org; Wed, 04 Nov 2020 16:38:02 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=P/u2TF3oLcMxz3Wi4ZjMGw/7l9riNiufmGsS03PjdnQ=; b=SV1Q76qAq9NL10KuDO3HZIh5WZ ClhIDefsooYFvHzjdhyQlCy9uItacSE1no5LkH6CKQOlG0JPtJkofYxYBVmV3/EAsMU57Sql/OUjX bpyh7r2hT25LOULftRoPVyNR2Igi6nQuSLOh9HsyBN7SnRQnrweWZCutflGNkGXX66o/u5H2OUs0M /yofyKH41v8BQHxDWZIFSwAvzCNAK3gcCmPxt0vpaQslcyMtSPggjNGmQwbctMK4XiwL2xqdcwH2E tSfjmYIaJ9rEKCn/PPkUDoAnSmBE45GYCNSCNSISFljHATk9bDrm/JvO+TyzT4v5yh2DC9jFxBWN8 5VZgiqlA==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaLnL-0004eR-0B; Wed, 04 Nov 2020 16:37:59 +0000 Date: Wed, 4 Nov 2020 16:37:58 +0000 From: Christoph Hellwig To: Daniel Vetter Subject: Re: [PATCH v5 05/15] mm/frame-vector: Use FOLL_LONGTERM Message-ID: <20201104163758.GA17425@infradead.org> References: <446b2d5b-a1a1-a408-f884-f17a04b72c18@nvidia.com> <1f7cf690-35e2-c56f-6d3f-94400633edd2@nvidia.com> <7f29a42a-c408-525d-90b7-ef3c12b5826c@nvidia.com> <20201104140023.GQ36674@ziepe.ca> <20201104162125.GA13007@infradead.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-samsung-soc , Jan Kara , KVM list , Pawel Osciak , Linux MM , John Hubbard , LKML , DRI Development , Tomasz Figa , Christoph Hellwig , Jason Gunthorpe , J??r??me Glisse , "open list:DMA BUFFER SHARING FRAMEWORK" , Daniel Vetter , Kyungmin Park , Andrew Morton , Mauro Carvalho Chehab , Dan Williams , Linux ARM , Marek Szyprowski Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Nov 04, 2020 at 05:26:58PM +0100, Daniel Vetter wrote: > What we're discussing is whether gup_fast and pup_fast also obey this, > or fall over and can give you the struct page that's backing the > dma_mmap_* memory. Since the _fast variant doesn't check for > vma->vm_flags, and afaict that's the only thing which closes this gap. > And like you restate, that would be a bit a problem. So where's that > check which Jason&me aren't spotting? remap_pte_range uses pte_mkspecial to set up the PTEs, and gup_pte_range errors out on pte_special. Of course this only works for the CONFIG_ARCH_HAS_PTE_SPECIAL case, for other architectures we do have a real problem. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel