From patchwork Mon Aug 14 21:53:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?TWljaGHFgiBNaXJvc8WCYXc=?= X-Patchwork-Id: 801341 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-tegra-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=rere.qmqm.pl header.i=@rere.qmqm.pl header.b="omYo+jq8"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3xWTrs5wRnz9sNn for ; Tue, 15 Aug 2017 07:53:49 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752413AbdHNVxs (ORCPT ); Mon, 14 Aug 2017 17:53:48 -0400 Received: from 78-11-180-123.static.ip.netia.com.pl ([78.11.180.123]:49232 "EHLO rere.qmqm.pl" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752408AbdHNVxs (ORCPT ); Mon, 14 Aug 2017 17:53:48 -0400 Received: from remote.user (localhost [127.0.0.1]) by rere.qmqm.pl (Postfix) with ESMTPSA id 3xWTrp1qzTz39; Mon, 14 Aug 2017 23:53:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=rere.qmqm.pl; s=1; t=1502747626; bh=hR8kTpy0r7PzabQATKORPzaawWkNlQvba1+ddzT5vCk=; h=Date:From:Subject:To:Cc:From; b=omYo+jq8Uckra5SkFI7ZMkKKqhMnIhYxfCnyy+zQo/1ya0qe9e3ZhjJlmH7S01uFH Vr+vLWUc45N5jqm7QtSk35KH8wVSQdBVyElZyxVhbAJHiYtpELYrrpuCCjz1m+Fsa4 acWRb+4Eovvu7g72xZlaVfVVmG037hb0WQFvAGTqjrnjZMem+C3u2IHdjx13qJoCnF +xLsW1vV1tjbtSGTImGl4cLM2k+w4cKUrNKidwLbKZ8xFeji08H3R9MQqhbi55jj9j krv4UseIAxPKmbxakXY4XKiGYj0IYMBqHK3WsKg5WlJnfElupfZgf4MBMf24OB5T/J +enpC/bd3+gbw== X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.99.2 at rere Date: Mon, 14 Aug 2017 23:53:45 +0200 Message-Id: <7ca7b47df4aa1c164b7313172564923a2639dcc1.1502747460.git.mirq-linux@rere.qmqm.pl> From: =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= Subject: [PATCH] drm: tegra: fix NULL deref in debugfs/iova MIME-Version: 1.0 To: Thierry Reding , David Airlie , Jonathan Hunter Cc: dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org Sender: linux-tegra-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org When IOMMU is off, ->mm_lock is not initialized and ->mm is NULL. Signed-off-by: Michał Mirosław --- drivers/gpu/drm/tegra/drm.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c index 8b7842548b9f..f859c06b8ab0 100644 --- a/drivers/gpu/drm/tegra/drm.c +++ b/drivers/gpu/drm/tegra/drm.c @@ -1033,9 +1033,11 @@ static int tegra_debugfs_iova(struct seq_file *s, void *data) struct tegra_drm *tegra = drm->dev_private; struct drm_printer p = drm_seq_file_printer(s); - mutex_lock(&tegra->mm_lock); - drm_mm_print(&tegra->mm, &p); - mutex_unlock(&tegra->mm_lock); + if (tegra->domain) { + mutex_lock(&tegra->mm_lock); + drm_mm_print(&tegra->mm, &p); + mutex_unlock(&tegra->mm_lock); + } return 0; }