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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 ADF7DC67879 for ; Mon, 8 Oct 2018 23:24:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7484B2145D for ; Mon, 8 Oct 2018 23:24:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7484B2145D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726683AbeJIGi4 (ORCPT ); Tue, 9 Oct 2018 02:38:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48654 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725759AbeJIGiz (ORCPT ); Tue, 9 Oct 2018 02:38:55 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6946C308A94E; Mon, 8 Oct 2018 23:24:49 +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 5D50F6888C; Mon, 8 Oct 2018 23:24:48 +0000 (UTC) From: Lyude Paul To: intel-gfx@lists.freedesktop.org, nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org, Gustavo Padovan , Maarten Lankhorst , Sean Paul , David Airlie , linux-kernel@vger.kernel.org Subject: [PATCH v7 1/5] drm/atomic_helper: Disallow new modesets on unregistered connectors Date: Mon, 8 Oct 2018 19:24:30 -0400 Message-Id: <20181008232437.5571-2-lyude@redhat.com> In-Reply-To: <20181008232437.5571-1-lyude@redhat.com> References: <20181008232437.5571-1-lyude@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Mon, 08 Oct 2018 23:24:49 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With the exception of modesets which would switch the DPMS state of a connector from on to off, we want to make sure that we disallow all modesets which would result in enabling a new monitor or a new mode configuration on a monitor if the connector for the display in question is no longer registered. This allows us to stop userspace from trying to enable new displays on connectors for an MST topology that were just removed from the system, without preventing userspace from disabling DPMS on those connectors. Changes since v5: - Fix typo in comment, nothing else Signed-off-by: Lyude Paul Reviewed-by: Daniel Vetter Cc: stable@vger.kernel.org --- drivers/gpu/drm/drm_atomic_helper.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 6f66777dca4b..e6a2cf72de5e 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -319,6 +319,26 @@ update_connector_routing(struct drm_atomic_state *state, return 0; } + crtc_state = drm_atomic_get_new_crtc_state(state, + new_connector_state->crtc); + /* + * For compatibility with legacy users, we want to make sure that + * we allow DPMS On->Off modesets on unregistered connectors. Modesets + * which would result in anything else must be considered invalid, to + * avoid turning on new displays on dead connectors. + * + * Since the connector can be unregistered at any point during an + * atomic check or commit, this is racy. But that's OK: all we care + * about is ensuring that userspace can't do anything but shut off the + * display on a connector that was destroyed after its been notified, + * not before. + */ + if (!READ_ONCE(connector->registered) && crtc_state->active) { + DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n", + connector->base.id, connector->name); + return -EINVAL; + } + funcs = connector->helper_private; if (funcs->atomic_best_encoder) @@ -363,7 +383,6 @@ update_connector_routing(struct drm_atomic_state *state, set_best_encoder(state, new_connector_state, new_encoder); - crtc_state = drm_atomic_get_new_crtc_state(state, new_connector_state->crtc); crtc_state->connectors_changed = true; DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d:%s]\n", -- 2.17.1