From patchwork Sun Jun 7 21:25:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Imre Deak X-Patchwork-Id: 11592299 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D3EEB618 for ; Sun, 7 Jun 2020 21:25:37 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BB44D2073B for ; Sun, 7 Jun 2020 21:25:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BB44D2073B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A1AF86E185; Sun, 7 Jun 2020 21:25:30 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4E6876E0B7; Sun, 7 Jun 2020 21:25:29 +0000 (UTC) IronPort-SDR: AUcy4zek1upvualNQuwztIW4MYZqSMyxYnuIaL+qGXFA9Id/HO4qrQZOR87mUdwEg7iILcJX4H YNUAtMfb2OcQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jun 2020 14:25:28 -0700 IronPort-SDR: SmnAHvw9l+jvzaBdh3BczrDKs8dLSbTDUNpLYM5MTNMCHIEt+cdbk9DpzbxOeBZFpS5VnZOK9I twGEyIP/pz1w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,485,1583222400"; d="scan'208";a="270317161" Received: from ideak-desk.fi.intel.com ([10.237.72.183]) by orsmga003.jf.intel.com with ESMTP; 07 Jun 2020 14:25:27 -0700 From: Imre Deak To: intel-gfx@lists.freedesktop.org Subject: [PATCH 1/3] drm/dp_mst: Fix the DDC I2C device unregistration of an MST port Date: Mon, 8 Jun 2020 00:25:20 +0300 Message-Id: <20200607212522.16935-1-imre.deak@intel.com> X-Mailer: git-send-email 2.23.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: stable@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The WARN below triggers during the removal of an MST port. The problem is that the parent device's (the connector's kdev) sysfs directory is removed recursively when the connector is unregistered (even though the I2C device holds a reference on the parent device). To fix this set first the Peer Device Type to none which will remove the I2C device. Note that atm, inconsistently, the parent of the I2C device is initially set to the DRM kdev and after a Connection Status Notification the parent may be reset to be the connector's kdev. This problem is addressed by the next patch. [ 4462.989299] ------------[ cut here ]------------ [ 4463.014940] sysfs group 'power' not found for kobject 'i2c-24' [ 4463.034664] WARNING: CPU: 0 PID: 970 at fs/sysfs/group.c:281 sysfs_remove_group+0x71/0x80 [ 4463.044357] Modules linked in: snd_hda_intel i915 drm_kms_helper(O) drm netconsole snd_hda_codec_hdmi mei_hdcp x86_pkg_temp_thermal coretemp crct10dif_pclmul snd_intel_dspcf g crc32_pclmul snd_hda_codec snd_hwdep ghash_clmulni_intel snd_hda_core asix usbnet kvm_intel mii i2c_algo_bit snd_pcm syscopyarea sysfillrect e1000e sysimgblt fb_sys_fops prim e_numbers ptp pps_core i2c_i801 r8169 mei_me realtek mei [last unloaded: drm] [ 4463.044399] CPU: 0 PID: 970 Comm: kworker/0:2 Tainted: G O 5.7.0+ #172 [ 4463.044402] Hardware name: Intel Corporation Tiger Lake Client Platform/TigerLake U DDR4 SODIMM RVP [ 4463.044423] Workqueue: events drm_dp_delayed_destroy_work [drm_kms_helper] [ 4463.044428] RIP: 0010:sysfs_remove_group+0x71/0x80 [ 4463.044431] Code: 48 89 df 5b 5d 41 5c e9 cd b6 ff ff 48 89 df e8 95 b4 ff ff eb cb 49 8b 14 24 48 8b 75 00 48 c7 c7 20 0f 3f 82 e8 9f c5 d7 ff <0f> 0b 5b 5d 41 5c c3 0f 1f 84 00 00 00 00 00 48 85 f6 74 31 41 54 [ 4463.044433] RSP: 0018:ffffc900018bfbf0 EFLAGS: 00010282 [ 4463.044436] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 [ 4463.044439] RDX: 0000000080000001 RSI: ffff88849e828f38 RDI: 00000000ffffffff [ 4463.052970] [drm:drm_atomic_get_plane_state [drm]] Added [PLANE:100:plane 2B] 00000000c2160caa state to 00000000d172564a [ 4463.070533] RBP: ffffffff820cea20 R08: ffff88847f4b8958 R09: 0000000000000000 [ 4463.070535] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88848a725018 [ 4463.070537] R13: 0000000000000000 R14: ffffffff827090e0 R15: 0000000000000002 [ 4463.070539] FS: 0000000000000000(0000) GS:ffff88849e800000(0000) knlGS:0000000000000000 [ 4463.070541] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4463.070543] CR2: 00007fdf8a756538 CR3: 0000000489684001 CR4: 0000000000760ef0 [ 4463.070545] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4463.070547] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4463.070549] PKRU: 55555554 [ 4463.070551] Call Trace: [ 4463.070560] device_del+0x84/0x400 [ 4463.070571] cdev_device_del+0x10/0x30 [ 4463.070578] put_i2c_dev+0x69/0x80 [ 4463.070584] i2cdev_detach_adapter+0x2e/0x60 [ 4463.070591] notifier_call_chain+0x34/0x90 [ 4463.070599] blocking_notifier_call_chain+0x3f/0x60 [ 4463.070606] device_del+0x7c/0x400 [ 4463.087817] ? lockdep_init_map_waits+0x57/0x210 [ 4463.087825] device_unregister+0x11/0x60 [ 4463.087829] i2c_del_adapter+0x249/0x310 [ 4463.087846] drm_dp_port_set_pdt+0x6b/0x2c0 [drm_kms_helper] [ 4463.087862] drm_dp_delayed_destroy_work+0x2af/0x350 [drm_kms_helper] [ 4463.087876] process_one_work+0x268/0x600 [ 4463.105438] ? __schedule+0x30c/0x920 [ 4463.105451] worker_thread+0x37/0x380 [ 4463.105457] ? process_one_work+0x600/0x600 [ 4463.105462] kthread+0x140/0x160 [ 4463.105466] ? kthread_park+0x80/0x80 [ 4463.105474] ret_from_fork+0x24/0x50 Cc: Signed-off-by: Imre Deak Reviewed-by: Stanislav Lisovskiy --- drivers/gpu/drm/drm_dp_mst_topology.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 2a309fb2c4cc..02c800b8199f 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -4669,12 +4669,13 @@ static void drm_dp_tx_work(struct work_struct *work) static inline void drm_dp_delayed_destroy_port(struct drm_dp_mst_port *port) { + drm_dp_port_set_pdt(port, DP_PEER_DEVICE_NONE, port->mcs); + if (port->connector) { drm_connector_unregister(port->connector); drm_connector_put(port->connector); } - drm_dp_port_set_pdt(port, DP_PEER_DEVICE_NONE, port->mcs); drm_dp_mst_put_port_malloc(port); } From patchwork Sun Jun 7 21:25:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Imre Deak X-Patchwork-Id: 11592303 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 82D88618 for ; Sun, 7 Jun 2020 21:25:41 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6AACB2078B for ; Sun, 7 Jun 2020 21:25:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6AACB2078B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0EBA86E1F3; Sun, 7 Jun 2020 21:25:33 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1F1AA6E1F3; Sun, 7 Jun 2020 21:25:31 +0000 (UTC) IronPort-SDR: Chj/mk8k3uB8kVzyaz5PUrSCMqhxOk0mmew3rk8YdjCvLAj1XkvKbaLBm5WVp5ByIPhJ5Nlj/V 4tJJj1ZRCyew== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jun 2020 14:25:30 -0700 IronPort-SDR: kIuXvujiVBRu8DPzrjhtSBz9LifRZZM00MPAOqrF3ms14XUfOuHxSwOJD1CYGHK2vOPNnn7JzU VjGSA7YyL1oA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,485,1583222400"; d="scan'208";a="270317164" Received: from ideak-desk.fi.intel.com ([10.237.72.183]) by orsmga003.jf.intel.com with ESMTP; 07 Jun 2020 14:25:28 -0700 From: Imre Deak To: intel-gfx@lists.freedesktop.org Subject: [PATCH 2/3] drm/dp_mst: Fix the DDC I2C device registration of an MST port Date: Mon, 8 Jun 2020 00:25:21 +0300 Message-Id: <20200607212522.16935-2-imre.deak@intel.com> X-Mailer: git-send-email 2.23.1 In-Reply-To: <20200607212522.16935-1-imre.deak@intel.com> References: <20200607212522.16935-1-imre.deak@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: stable@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" During the initial MST probing an MST port's I2C device will be registered using the kdev of the DRM device as a parent. Later after MST Connection Status Notifications this I2C device will be re-registered with the kdev of the port's connector. This will also move inconsistently the I2C device's sysfs entry from the DRM device's sysfs dir to the connector's dir. Fix the above by keeping the DRM kdev as the parent of the I2C device. Ideally the connector's kdev would be used as a parent, similarly to non-MST connectors, however that needs some more refactoring to ensure the connector's kdev is already available early enough. So keep the existing (initial) behavior for now. Cc: Signed-off-by: Imre Deak Reviewed-by: Stanislav Lisovskiy --- drivers/gpu/drm/drm_dp_mst_topology.c | 28 +++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 02c800b8199f..083255c33ee0 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -88,8 +88,8 @@ static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, u8 *guid); -static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux); -static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux); +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); #define DBG_PREFIX "[dp_mst]" @@ -1993,7 +1993,7 @@ drm_dp_port_set_pdt(struct drm_dp_mst_port *port, u8 new_pdt, } /* remove i2c over sideband */ - drm_dp_mst_unregister_i2c_bus(&port->aux); + drm_dp_mst_unregister_i2c_bus(port); } else { mutex_lock(&mgr->lock); drm_dp_mst_topology_put_mstb(port->mstb); @@ -2008,7 +2008,7 @@ drm_dp_port_set_pdt(struct drm_dp_mst_port *port, u8 new_pdt, if (port->pdt != DP_PEER_DEVICE_NONE) { if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { /* add i2c over sideband */ - ret = drm_dp_mst_register_i2c_bus(&port->aux); + ret = drm_dp_mst_register_i2c_bus(port); } else { lct = drm_dp_calculate_rad(port, rad); mstb = drm_dp_add_mst_branch_device(lct, rad); @@ -5375,22 +5375,26 @@ static const struct i2c_algorithm drm_dp_mst_i2c_algo = { /** * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX - * @aux: DisplayPort AUX channel + * @port: The port to add the I2C bus on * * Returns 0 on success or a negative error code on failure. */ -static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux) +static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port) { + struct drm_dp_aux *aux = &port->aux; + struct device *parent_dev = port->mgr->dev->dev; + aux->ddc.algo = &drm_dp_mst_i2c_algo; aux->ddc.algo_data = aux; aux->ddc.retries = 3; aux->ddc.class = I2C_CLASS_DDC; aux->ddc.owner = THIS_MODULE; - aux->ddc.dev.parent = aux->dev; - aux->ddc.dev.of_node = aux->dev->of_node; + /* FIXME: set the kdev of the port's connector as parent */ + aux->ddc.dev.parent = parent_dev; + aux->ddc.dev.of_node = parent_dev->of_node; - strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), + strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(parent_dev), sizeof(aux->ddc.name)); return i2c_add_adapter(&aux->ddc); @@ -5398,11 +5402,11 @@ static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux) /** * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter - * @aux: DisplayPort AUX channel + * @port: The port to remove the I2C bus from */ -static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux) +static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port) { - i2c_del_adapter(&aux->ddc); + i2c_del_adapter(&port->aux.ddc); } /** From patchwork Sun Jun 7 21:25:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Imre Deak X-Patchwork-Id: 11592305 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 912BF618 for ; Sun, 7 Jun 2020 21:25:43 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 783952073B for ; Sun, 7 Jun 2020 21:25:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 783952073B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 94BC66E202; Sun, 7 Jun 2020 21:25:35 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 32B586E1C0; Sun, 7 Jun 2020 21:25:32 +0000 (UTC) IronPort-SDR: LniwemmxuZDJZoUd10CzaVbpy7VqZshMAmezVNeQ1+n8kE584dkqXb6jinHEGY6HWzvWAnwVyJ SW7CiCjIDUww== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jun 2020 14:25:31 -0700 IronPort-SDR: Ubunfb68a83ey9+2yk6CzmgD1PEARNmg9IkTCcwb3BzuwvKEhAl6n24pS6luGRzRFOpiilMnLW HBNyZHz+JteA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,485,1583222400"; d="scan'208";a="270317167" Received: from ideak-desk.fi.intel.com ([10.237.72.183]) by orsmga003.jf.intel.com with ESMTP; 07 Jun 2020 14:25:30 -0700 From: Imre Deak To: intel-gfx@lists.freedesktop.org Subject: [PATCH 3/3] drm/dp_mst: Fix flushing the delayed port/mstb destroy work Date: Mon, 8 Jun 2020 00:25:22 +0300 Message-Id: <20200607212522.16935-3-imre.deak@intel.com> X-Mailer: git-send-email 2.23.1 In-Reply-To: <20200607212522.16935-1-imre.deak@intel.com> References: <20200607212522.16935-1-imre.deak@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Atm, a pending delayed destroy work during module removal will be canceled, leaving behind MST ports, mstbs. Fix this by using a dedicated workqueue which will be drained of requeued items as well when destroying it. Signed-off-by: Imre Deak Reviewed-by: Stanislav Lisovskiy --- drivers/gpu/drm/drm_dp_mst_topology.c | 17 ++++++++++++++--- include/drm/drm_dp_mst_helper.h | 8 ++++++++ 2 files changed, 22 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 083255c33ee0..075fb5ac9264 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -1630,7 +1630,7 @@ static void drm_dp_destroy_mst_branch_device(struct kref *kref) mutex_lock(&mgr->delayed_destroy_lock); list_add(&mstb->destroy_next, &mgr->destroy_branch_device_list); mutex_unlock(&mgr->delayed_destroy_lock); - schedule_work(&mgr->delayed_destroy_work); + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); } /** @@ -1747,7 +1747,7 @@ static void drm_dp_destroy_port(struct kref *kref) mutex_lock(&mgr->delayed_destroy_lock); list_add(&port->next, &mgr->destroy_port_list); mutex_unlock(&mgr->delayed_destroy_lock); - schedule_work(&mgr->delayed_destroy_work); + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); } /** @@ -5208,6 +5208,15 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, INIT_LIST_HEAD(&mgr->destroy_port_list); INIT_LIST_HEAD(&mgr->destroy_branch_device_list); INIT_LIST_HEAD(&mgr->up_req_list); + + /* + * delayed_destroy_work will be queued on a dedicated WQ, so that any + * requeuing will be also flushed when deiniting the topology manager. + */ + mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0); + if (mgr->delayed_destroy_wq == NULL) + return -ENOMEM; + INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); INIT_WORK(&mgr->tx_work, drm_dp_tx_work); INIT_WORK(&mgr->delayed_destroy_work, drm_dp_delayed_destroy_work); @@ -5252,7 +5261,9 @@ void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) { drm_dp_mst_topology_mgr_set_mst(mgr, false); flush_work(&mgr->work); - cancel_work_sync(&mgr->delayed_destroy_work); + /* The following will also drain any requeued work on the WQ. */ + destroy_workqueue(mgr->delayed_destroy_wq); + mgr->delayed_destroy_wq = NULL; mutex_lock(&mgr->payload_lock); kfree(mgr->payloads); mgr->payloads = NULL; diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h index b230ff6f7081..8b9eb4db3381 100644 --- a/include/drm/drm_dp_mst_helper.h +++ b/include/drm/drm_dp_mst_helper.h @@ -681,6 +681,14 @@ struct drm_dp_mst_topology_mgr { * @destroy_branch_device_list. */ struct mutex delayed_destroy_lock; + + /** + * @delayed_destroy_wq: Workqueue used for delayed_destroy_work items. + * A dedicated WQ makes it possible to drain any requeued work items + * on it. + */ + struct workqueue_struct *delayed_destroy_wq; + /** * @delayed_destroy_work: Work item to destroy MST port and branch * devices, needed to avoid locking inversion.