From patchwork Mon Oct 26 10:58:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11856555 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=-12.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 940B6C8300C for ; Mon, 26 Oct 2020 10:58:51 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 503072231B for ; Mon, 26 Oct 2020 10:58:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="BE6oxOGm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 503072231B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3BE796E9B9; Mon, 26 Oct 2020 10:58:46 +0000 (UTC) Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by gabe.freedesktop.org (Postfix) with ESMTPS id CEB226E96E for ; Mon, 26 Oct 2020 10:58:39 +0000 (UTC) Received: by mail-wr1-x442.google.com with SMTP id e17so11866564wru.12 for ; Mon, 26 Oct 2020 03:58:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=fFEiUvLl06c3j38++d5NzLL6L7leWWZ4E8u91rYq/3A=; b=BE6oxOGm6LpmFehTBcLW4JPuAVn0ztXRRhPFdKmp1PBfZHMfOH6ZZMUim7N+RidGFG 0CE8UiBULFscc13H0ar8GrDLO4yJ1P0bnnkFlnldicZz6vS1PSOwsA2+DLJdMtAv2h85 Tg25hld8e9Oy330GCD/SQEbTeh0mowIk6eEfA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=fFEiUvLl06c3j38++d5NzLL6L7leWWZ4E8u91rYq/3A=; b=cjmxciQRlPj1di65a0pVk3E2vWSzAmetSIacQbYYZ/GCd7TqHUki+RDxTbrlbLlFHY fdysnCA38VXN/rJloXJWK2FflRdDvjRRAio1kYrxjrZFfl1bjk7Oa/c9/uVHdGNMA8bh HsJ/DWbJt3l/KFukOd2278IqWscwFyfibdET3x4seKJU76aTj1E/N+rrlHqp3B7+9BSH ZlcUAglfJuU2JqkCL3NWwqWpIvhZDh2HrP2BfrlRS3gAtLIUFVfWjil4sKscx964XJf6 I4APnIOfTsw2LhgpuIMzgD0Bz5F3PcI8UXBurzqO/xXWYMbkRmKy8IDPhYzfvOE8nkJs WdyA== X-Gm-Message-State: AOAM53011ac8ydFsWe7IJcy5+H+ydgXKmasz3N9QP7O/jDqDf/J7SdqB gy5QIXdbQRV3ulqsHZzJ0f8c0WAf3+65t077 X-Google-Smtp-Source: ABdhPJyJPBqr4xzE4feUIHJFFKeriugShRo0uGRtLd+TVzcLzKKWgkZaYccYEU5/Oo10Zk0lMDMkEw== X-Received: by 2002:a05:6000:12c9:: with SMTP id l9mr16792055wrx.309.1603709918272; Mon, 26 Oct 2020 03:58:38 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id w83sm21165156wmg.48.2020.10.26.03.58.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 26 Oct 2020 03:58:37 -0700 (PDT) From: Daniel Vetter To: DRI Development , LKML Subject: [PATCH v4 09/15] media/videbuf1|2: Mark follow_pfn usage as unsafe Date: Mon, 26 Oct 2020 11:58:12 +0100 Message-Id: <20201026105818.2585306-10-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201026105818.2585306-1-daniel.vetter@ffwll.ch> References: <20201026105818.2585306-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jan Kara , kvm@vger.kernel.org, Daniel Vetter , linux-mm@kvack.org, Daniel Vetter , Michel Lespinasse , Marek Szyprowski , linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, Daniel Jordan , Jason Gunthorpe , linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, Kees Cook , Pawel Osciak , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Dan Williams , Laurent Dufour , Vlastimil Babka , Tomasz Figa , Kyungmin Park , Andrew Morton Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The media model assumes that buffers are all preallocated, so that when a media pipeline is running we never miss a deadline because the buffers aren't allocated or available. This means we cannot fix the v4l follow_pfn usage through mmu_notifier, without breaking how this all works. The only real fix is to deprecate userptr support for VM_IO | VM_PFNMAP mappings and tell everyone to cut over to dma-buf memory sharing for zerocopy. userptr for normal memory will keep working as-is, this only affects the zerocopy userptr usage enabled in 50ac952d2263 ("[media] videobuf2-dma-sg: Support io userptr operations on io memory"). Signed-off-by: Daniel Vetter Cc: Jason Gunthorpe Cc: Kees Cook Cc: Dan Williams Cc: Andrew Morton Cc: John Hubbard Cc: Jérôme Glisse Cc: Jan Kara Cc: Dan Williams Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Pawel Osciak Cc: Marek Szyprowski Cc: Kyungmin Park Cc: Tomasz Figa Cc: Laurent Dufour Cc: Vlastimil Babka Cc: Daniel Jordan Cc: Michel Lespinasse Signed-off-by: Daniel Vetter Acked-by: Tomasz Figa --- v3: - Reference the commit that enabled the zerocopy userptr use case to make it abundandtly clear that this patch only affects that, and not normal memory userptr. The old commit message already explained that normal memory userptr is unaffected, but I guess that was not clear enough. --- drivers/media/common/videobuf2/frame_vector.c | 2 +- drivers/media/v4l2-core/videobuf-dma-contig.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/common/videobuf2/frame_vector.c b/drivers/media/common/videobuf2/frame_vector.c index 6590987c14bd..e630494da65c 100644 --- a/drivers/media/common/videobuf2/frame_vector.c +++ b/drivers/media/common/videobuf2/frame_vector.c @@ -69,7 +69,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, break; while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) { - err = follow_pfn(vma, start, &nums[ret]); + err = unsafe_follow_pfn(vma, start, &nums[ret]); if (err) { if (ret == 0) ret = err; diff --git a/drivers/media/v4l2-core/videobuf-dma-contig.c b/drivers/media/v4l2-core/videobuf-dma-contig.c index 52312ce2ba05..821c4a76ab96 100644 --- a/drivers/media/v4l2-core/videobuf-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf-dma-contig.c @@ -183,7 +183,7 @@ static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem, user_address = untagged_baddr; while (pages_done < (mem->size >> PAGE_SHIFT)) { - ret = follow_pfn(vma, user_address, &this_pfn); + ret = unsafe_follow_pfn(vma, user_address, &this_pfn); if (ret) break;