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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 975A7C35640 for ; Fri, 21 Feb 2020 08:25:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 638FB2469F for ; Fri, 21 Feb 2020 08:25:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582273510; bh=J82JkTofHDDCykmw5UKeVbFfNcfQzl+TMlBOTvHz5nY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DpLULOgOmQSHhLE4som1LSYBS0o7VvP55rOWmHnBEa80RuTLjx4BEdBtEORtnnXpu 9/tO37XdD2VTuQe/Oe905QQeUr6DcQ2elrcHE6hPYHjM0AHwp7770W6Nz/61mfGlFH xAScWqUZXBhwh181nMVDjD22Zvo+RGsAv2ZtXnt0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388760AbgBUIZJ (ORCPT ); Fri, 21 Feb 2020 03:25:09 -0500 Received: from mail.kernel.org ([198.145.29.99]:37788 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388306AbgBUIZF (ORCPT ); Fri, 21 Feb 2020 03:25:05 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D85AD2469F; Fri, 21 Feb 2020 08:25:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582273505; bh=J82JkTofHDDCykmw5UKeVbFfNcfQzl+TMlBOTvHz5nY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Df1ctL+eHaK/b2pvXAFjqADRNLgXmaUgkjIeos4aSPGUHmAjSuBEobvyHZ5qtkUfT zWoOBw6ovLP23gWDBfN6OUybv0DxG50AFAYHSYuGiuPRxnfHfbwgfgu/h/QoqFDmZC N+cnZ1XZIH3GN883taknSm4UShacURRbj3w7fxA4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ben Skeggs , Sasha Levin Subject: [PATCH 4.19 172/191] drm/nouveau/disp/nv50-: prevent oops when no channel method map provided Date: Fri, 21 Feb 2020 08:42:25 +0100 Message-Id: <20200221072311.291921344@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200221072250.732482588@linuxfoundation.org> References: <20200221072250.732482588@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ben Skeggs [ Upstream commit 0e6176c6d286316e9431b4f695940cfac4ffe6c2 ] The implementations for most channel types contains a map of methods to priv registers in order to provide debugging info when a disp exception has been raised. This info is missing from the implementation of PIO channels as they're rather simplistic already, however, if an exception is raised by one of them, we'd end up triggering a NULL-pointer deref. Not ideal... Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206299 Signed-off-by: Ben Skeggs Signed-off-by: Sasha Levin --- drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c index bcf32d92ee5a9..50e3539f33d22 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c @@ -74,6 +74,8 @@ nv50_disp_chan_mthd(struct nv50_disp_chan *chan, int debug) if (debug > subdev->debug) return; + if (!mthd) + return; for (i = 0; (list = mthd->data[i].mthd) != NULL; i++) { u32 base = chan->head * mthd->addr; -- 2.20.1