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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 F1D86C07E96 for ; Thu, 15 Jul 2021 12:31:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D3E1A6136E for ; Thu, 15 Jul 2021 12:31:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229604AbhGOMeT (ORCPT ); Thu, 15 Jul 2021 08:34:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:36468 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229595AbhGOMeT (ORCPT ); Thu, 15 Jul 2021 08:34:19 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5995E61178; Thu, 15 Jul 2021 12:31:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626352285; bh=+8WklqRIPbMK19FjViu3eg+7qwGpJSy+13/U9X/Qr9g=; h=Subject:To:Cc:From:Date:From; b=GU4lDjpjrw0Pkt4FQpCKx/my6/grXg0DoPDELIS31mAqH2xNQ/kGApD9ZLaHsv15L uZZr17bEx9dQFE7j55o7xIWXJFfe3vTXLiP7cXlMwJeb44W9I9GZcjKN5GRZwjRKsV 1thY9OFW5W6b5sddVmxCZ/RLSQa6KehtLZa3O4+w= Subject: FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree To: Wayne.Lin@amd.com, lyude@redhat.com Cc: From: Date: Thu, 15 Jul 2021 14:17:18 +0200 Message-ID: <16263514381332@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.13-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 3769e4c0af5b82c8ea21d037013cb9564dfaa51f Mon Sep 17 00:00:00 2001 From: Wayne Lin Date: Wed, 16 Jun 2021 11:55:01 +0800 Subject: [PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale topology [Why] After unplug/hotplug hub from the system, userspace might start to clear stale payloads gradually. If we call drm_dp_mst_deallocate_vcpi() to release stale VCPI of those ports which are not relating to current topology, we have chane to wrongly clear active payload table entry for current topology. E.g. We have allocated VCPI 1 in current payload table and we call drm_dp_mst_deallocate_vcpi() to clean VCPI 1 in stale topology. In drm_dp_mst_deallocate_vcpi(), it will call drm_dp_mst_put_payload_id() tp put VCPI 1 and which means ID 1 is available again. Thereafter, if we want to allocate a new payload stream, it will find ID 1 is available by drm_dp_mst_assign_payload_id(). However, ID 1 is being used [How] Check target sink is relating to current topology or not before doing any payload table update. Searching upward to find the target sink's relevant root branch device. If the found root branch device is not the same root of current topology, don't update payload table. Changes since v1: * Change debug macro to use drm_dbg_kms() instead * Amend the commit message to add Cc tag. Signed-off-by: Wayne Lin Cc: stable@vger.kernel.org Signed-off-by: Lyude Paul Link: https://patchwork.freedesktop.org/patch/msgid/20210616035501.3776-3-Wayne.Lin@amd.com Reviewed-by: Lyude Paul diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index b41b837db66d..9ac148efd9e4 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -94,6 +94,9 @@ static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port); static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port); static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr); +static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port, + struct drm_dp_mst_branch *branch); + #define DBG_PREFIX "[dp_mst]" #define DP_STR(x) [DP_ ## x] = #x @@ -3366,6 +3369,7 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr) struct drm_dp_mst_port *port; int i, j; int cur_slots = 1; + bool skip; mutex_lock(&mgr->payload_lock); for (i = 0; i < mgr->max_payloads; i++) { @@ -3380,6 +3384,14 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr) port = container_of(vcpi, struct drm_dp_mst_port, vcpi); + mutex_lock(&mgr->lock); + skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary); + mutex_unlock(&mgr->lock); + + if (skip) { + drm_dbg_kms("Virtual channel %d is not in current topology\n", i); + continue; + } /* Validated ports don't matter if we're releasing * VCPI */ @@ -3479,6 +3491,7 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr) struct drm_dp_mst_port *port; int i; int ret = 0; + bool skip; mutex_lock(&mgr->payload_lock); for (i = 0; i < mgr->max_payloads; i++) { @@ -3488,6 +3501,13 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr) port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); + mutex_lock(&mgr->lock); + skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary); + mutex_unlock(&mgr->lock); + + if (skip) + continue; + drm_dbg_kms(mgr->dev, "payload %d %d\n", i, mgr->payloads[i].payload_state); if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) { ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]); @@ -4574,9 +4594,18 @@ EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots); void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { + bool skip; + if (!port->vcpi.vcpi) return; + mutex_lock(&mgr->lock); + skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary); + mutex_unlock(&mgr->lock); + + if (skip) + return; + drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); port->vcpi.num_slots = 0; port->vcpi.pbn = 0;