From patchwork Fri Oct 9 07:59:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11825275 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7ABCC109B for ; Fri, 9 Oct 2020 08:01:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D9B422277 for ; Fri, 9 Oct 2020 08:01:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="X+lVFEzk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732864AbgJIIBH (ORCPT ); Fri, 9 Oct 2020 04:01:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732739AbgJIIAN (ORCPT ); Fri, 9 Oct 2020 04:00:13 -0400 Received: from mail-wr1-x443.google.com (mail-wr1-x443.google.com [IPv6:2a00:1450:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05A09C0610CF for ; Fri, 9 Oct 2020 01:00:08 -0700 (PDT) Received: by mail-wr1-x443.google.com with SMTP id m6so9257860wrn.0 for ; Fri, 09 Oct 2020 01:00:07 -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=N5MezEhvq/wwBRTty0X109hZVMwHizCfP5Lc200+OeU=; b=X+lVFEzkJG7G1y1hQOMHpq9aH/9wMcZRASu3pf5WwWkSy+lBQfhcJFHkD+mB+HB+8B 6q3Z/oFWS+IjpKniri9mdKD+xWh4Pb1kxxRnhtmA75fRmXM2leSVVQ9O6mzJ2s2pjdNF FwYvxU8GuH0ylVTYs9gfzX5C6vRDllxk8cWjE= 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=N5MezEhvq/wwBRTty0X109hZVMwHizCfP5Lc200+OeU=; b=ZwvOsV98/4tTXxIHSRK6Y2wAudF7xq58u8FPOihLTQtdnmKxhHYAIFtAqLZfCrlaGy 92Yef0FbE4KmbIKtniRan9IDkS3DsZlvDKB0l/leEYpKLsNQN0btNh8UWXUKeWTqTXcy Cbmg256MYf1LXzI7Md34fQo5bMrWYP4SUqrEpeULO8XwoxNxjEHUESyfxg8ulFtGxZBr N9sWGGy6fPxcv96NJWng7kRxDqlLO4ilhaggJmCCPs2DJHY+6rU6aipdCyJ0Eq5a8sHe n31QmPvVlA3lwRJ8hycqXMQbdNz95vrpxrsoTu1JN/iHhfJYCYz4QQCBLnYALwoFE8vJ w9gA== X-Gm-Message-State: AOAM532/IK5NfS9TNBTIBXyJIzFju5Jqco+ryshEM/JqWJeU7XC3zQHz COg04CJuBFkgBc/NAMgyQ+Oy8w== X-Google-Smtp-Source: ABdhPJzMUouKiCH6SJK6dyAVSQS46IBJV9EJgv/XkHUvyqgT9BYelO/ICRgl0rBnswqZFheeRzPOMA== X-Received: by 2002:adf:9dd1:: with SMTP id q17mr6771139wre.317.1602230406671; Fri, 09 Oct 2020 01:00:06 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id u17sm11634118wri.45.2020.10.09.01.00.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Oct 2020 01:00:05 -0700 (PDT) From: Daniel Vetter To: DRI Development , LKML Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, linux-s390@vger.kernel.org, Daniel Vetter , Daniel Vetter , Jason Gunthorpe , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Pawel Osciak , Marek Szyprowski , Kyungmin Park , Tomasz Figa , Laurent Dufour , Vlastimil Babka , Daniel Jordan , Michel Lespinasse Subject: [PATCH v2 10/17] media/videbuf1|2: Mark follow_pfn usage as unsafe Date: Fri, 9 Oct 2020 09:59:27 +0200 Message-Id: <20201009075934.3509076-11-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201009075934.3509076-1-daniel.vetter@ffwll.ch> References: <20201009075934.3509076-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org 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. 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 --- 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 2b0b97761d15..a1b85fe9e7c1 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;