From patchwork Thu Dec 20 00:19:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 10738373 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3BA7D1399 for ; Thu, 20 Dec 2018 00:24:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2B3E82852D for ; Thu, 20 Dec 2018 00:24:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1F4A628747; Thu, 20 Dec 2018 00:24:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CA4F62852D for ; Thu, 20 Dec 2018 00:24:47 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 350F56F233; Thu, 20 Dec 2018 00:24:23 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id 095E26F22A; Thu, 20 Dec 2018 00:24:20 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 90631356E7; Thu, 20 Dec 2018 00:24:19 +0000 (UTC) Received: from malachite.bss.redhat.com (dhcp-10-20-1-11.bss.redhat.com [10.20.1.11]) by smtp.corp.redhat.com (Postfix) with ESMTP id 825C510018F8; Thu, 20 Dec 2018 00:24:18 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, nouveau@lists.freedesktop.org, amd-gfx@lists.freedesktop.org Subject: [PATCH v2 09/16] drm/nouveau: Remove unnecessary VCPI checks in nv50_msto_cleanup() Date: Wed, 19 Dec 2018 19:19:53 -0500 Message-Id: <20181220001959.12486-10-lyude@redhat.com> In-Reply-To: <20181220001959.12486-1-lyude@redhat.com> References: <20181220001959.12486-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 20 Dec 2018 00:24:19 +0000 (UTC) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jerry Zuo , David Airlie , Juston Li Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP There is no need to look at the port's VCPI allocation before calling drm_dp_mst_deallocate_vcpi(), as we already have msto->disabled to let us avoid cleaning up an msto more then once. The DP MST core will never call drm_dp_mst_deallocate_vcpi() on it's own, which is presumably what these checks are meant to protect against. More importantly though, we're about to stop clearing mstc->port in the next commit, which means if we could potentially hit a use-after-free error if we tried to check mstc->port->vcpi here. So to make life easier for anyone who bisects this code in the future, use msto->disabled instead to check whether or not we need to deallocate VCPI instead. Signed-off-by: Lyude Paul Cc: Daniel Vetter Cc: David Airlie Cc: Jerry Zuo Cc: Harry Wentland Cc: Juston Li --- drivers/gpu/drm/nouveau/dispnv50/disp.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c index 641252208e67..0f7d72518604 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -704,14 +704,17 @@ nv50_msto_cleanup(struct nv50_msto *msto) struct nv50_mstc *mstc = msto->mstc; struct nv50_mstm *mstm = mstc->mstm; + if (!msto->disabled) + return; + NV_ATOMIC(drm, "%s: msto cleanup\n", msto->encoder.name); - if (mstc->port && mstc->port->vcpi.vcpi > 0 && !nv50_msto_payload(msto)) + + if (mstc->port) drm_dp_mst_deallocate_vcpi(&mstm->mgr, mstc->port); - if (msto->disabled) { - msto->mstc = NULL; - msto->head = NULL; - msto->disabled = false; - } + + msto->mstc = NULL; + msto->head = NULL; + msto->disabled = false; } static void