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=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 A6F48C3F34D for ; Thu, 27 Feb 2020 13:49:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7C3C7246A1 for ; Thu, 27 Feb 2020 13:49:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582811364; bh=ky36aMu0AdjOm6TKsHBpxgM+ZwKEDz8HePbBtRxnoUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dHvUA8X0PFMDl+4FkxuMgda2m+s6LdYDOIc/7vaR3Wv1X6AbGi9kNTG0yR+3FC00D 6EbGdg6MdkkOPTCFwPet43TeKYoHsRKpagkWfEeTeu7L2LtzNe4ggDMwAoYnzZwLz0 QHVd+uZQovT5Nc4OeqnX9xd1AHZZOg02bUfRXXgI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731034AbgB0NtW (ORCPT ); Thu, 27 Feb 2020 08:49:22 -0500 Received: from mail.kernel.org ([198.145.29.99]:46580 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731021AbgB0NtR (ORCPT ); Thu, 27 Feb 2020 08:49:17 -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 AD53320801; Thu, 27 Feb 2020 13:49:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582811357; bh=ky36aMu0AdjOm6TKsHBpxgM+ZwKEDz8HePbBtRxnoUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MOwyslhLltGTKjk/hxhQPmRjjSqyZJnqWt93SHzrXOeA4XmONnoNZJDNQ9+PMv8M5 sxHdh/n0frWFt8mEddhtdmH/bmSDyB/Q4C/iLVJHpClAFYyT0yCsZCRJgR/Snsqt00 KbuloUmyPCTjkd8NOlxItXWJXeAsAMah5y2BZH1Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ben Skeggs , Sasha Levin Subject: [PATCH 4.9 102/165] drm/nouveau/disp/nv50-: prevent oops when no channel method map provided Date: Thu, 27 Feb 2020 14:36:16 +0100 Message-Id: <20200227132246.056555546@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200227132230.840899170@linuxfoundation.org> References: <20200227132230.840899170@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 9d90d8b4b7e65..f5a8db1bb8b72 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c @@ -72,6 +72,8 @@ 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