From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3555996-1521221671-2-16589964579577909773 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES enroca, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521221670; b=Uzoy60xOoJ5EH6n4/7rck2zPOX2KYf0fbKnPWM3/+YENUcX hpVEgwL3869AVlqzsd5/2h59ds208baQpkmQl54f+qu7fYxzBySmnjD0kEyaJ/wh B7gPi2paPQS/gI+xKx78ajOMnE5xT70rcoIOOZBoz1BXXj+eLBKi1gMHamX1zIln a3cWnMWrzUyx9Wg47UPCHk5fwNcdmYzqthHbs8OQdfPcmC6n60lZmlF0qdJ/w41c yekqurHnGsdkCFXzcyDH/P5lpCwv3gQXrszNknZh6S2Sv/cjsQsTwzVIHbtxsqi1 u+Fo/izZw7VH7wtDcahYJZiyFnv+snNVl4azEDw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1521221670; bh=0YdSRuqgC6OTplfVSHGgPFbrPL GueWcNwiqkPJAHyRI=; b=qs4UrfouhqFUzoX5AUEQoU85P5dZStptJXoP1sxRAT 7hxGKXuIaqc55DwOme6MKvUq/UXJb0dF8qdoEo11xfMhzatdmJOLnd070vNxdzkE 6eAy9ptUCGRW273slHx2dMM1RcN48ghXh/41bE6uziToR9twWCAjoTcquLmescIJ q0e3FB9yl/MMi/6N6bNf7kRPSXX24fAFH4EhSj0Vi0cjwmDCKRuJyp3g5Ybp7jTp UsB+xmtukvMdaayjf4xUNgM9wvrL5b7G1kV08l6gAVqGb7l3N16B8M2rLYtL/yiw N84qPCJTOl0prs1a+OfbNilO12/ZtVZqLE8MaP4JsPdA== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751014AbeCPReN (ORCPT ); Fri, 16 Mar 2018 13:34:13 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34092 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753920AbeCPP1I (ORCPT ); Fri, 16 Mar 2018 11:27:08 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ismo Toijala , Alex Deucher , Dave Airlie , Lyude Paul , Lukas Wunner Subject: [PATCH 4.4 08/63] drm/radeon: Fix deadlock on runtime suspend Date: Fri, 16 Mar 2018 16:22:40 +0100 Message-Id: <20180316152301.007767775@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180316152259.964532775@linuxfoundation.org> References: <20180316152259.964532775@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lukas Wunner commit 15734feff2bdac24aa3266c437cffa42851990e3 upstream. radeon's ->runtime_suspend hook calls drm_kms_helper_poll_disable(), which waits for the output poll worker to finish if it's running. The output poll worker meanwhile calls pm_runtime_get_sync() in radeon's ->detect hooks, which waits for the ongoing suspend to finish, causing a deadlock. Fix by not acquiring a runtime PM ref if the ->detect hooks are called in the output poll worker's context. This is safe because the poll worker is only enabled while runtime active and we know that ->runtime_suspend waits for it to finish. Stack trace for posterity: INFO: task kworker/0:3:31847 blocked for more than 120 seconds Workqueue: events output_poll_execute [drm_kms_helper] Call Trace: schedule+0x3c/0x90 rpm_resume+0x1e2/0x690 __pm_runtime_resume+0x3f/0x60 radeon_lvds_detect+0x39/0xf0 [radeon] output_poll_execute+0xda/0x1e0 [drm_kms_helper] process_one_work+0x14b/0x440 worker_thread+0x48/0x4a0 INFO: task kworker/2:0:10493 blocked for more than 120 seconds. Workqueue: pm pm_runtime_work Call Trace: schedule+0x3c/0x90 schedule_timeout+0x1b3/0x240 wait_for_common+0xc2/0x180 wait_for_completion+0x1d/0x20 flush_work+0xfc/0x1a0 __cancel_work_timer+0xa5/0x1d0 cancel_delayed_work_sync+0x13/0x20 drm_kms_helper_poll_disable+0x1f/0x30 [drm_kms_helper] radeon_pmops_runtime_suspend+0x3d/0xa0 [radeon] pci_pm_runtime_suspend+0x61/0x1a0 vga_switcheroo_runtime_suspend+0x21/0x70 __rpm_callback+0x32/0x70 rpm_callback+0x24/0x80 rpm_suspend+0x12b/0x640 pm_runtime_work+0x6f/0xb0 process_one_work+0x14b/0x440 worker_thread+0x48/0x4a0 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94147 Fixes: 10ebc0bc0934 ("drm/radeon: add runtime PM support (v2)") Cc: stable@vger.kernel.org # v3.13+: 27d4ee03078a: workqueue: Allow retrieval of current task's work struct Cc: stable@vger.kernel.org # v3.13+: 25c058ccaf2e: drm: Allow determining if current task is output poll worker Cc: Ismo Toijala Cc: Alex Deucher Cc: Dave Airlie Reviewed-by: Lyude Paul Signed-off-by: Lukas Wunner Link: https://patchwork.freedesktop.org/patch/msgid/64ea02c44f91dda19bc563902b97bbc699040392.1518338789.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/radeon/radeon_connectors.c | 74 +++++++++++++++++++---------- 1 file changed, 49 insertions(+), 25 deletions(-) --- a/drivers/gpu/drm/radeon/radeon_connectors.c +++ b/drivers/gpu/drm/radeon/radeon_connectors.c @@ -891,9 +891,11 @@ radeon_lvds_detect(struct drm_connector enum drm_connector_status ret = connector_status_disconnected; int r; - r = pm_runtime_get_sync(connector->dev->dev); - if (r < 0) - return connector_status_disconnected; + if (!drm_kms_helper_is_poll_worker()) { + r = pm_runtime_get_sync(connector->dev->dev); + if (r < 0) + return connector_status_disconnected; + } if (encoder) { struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder); @@ -916,8 +918,12 @@ radeon_lvds_detect(struct drm_connector /* check acpi lid status ??? */ radeon_connector_update_scratch_regs(connector, ret); - pm_runtime_mark_last_busy(connector->dev->dev); - pm_runtime_put_autosuspend(connector->dev->dev); + + if (!drm_kms_helper_is_poll_worker()) { + pm_runtime_mark_last_busy(connector->dev->dev); + pm_runtime_put_autosuspend(connector->dev->dev); + } + return ret; } @@ -1020,9 +1026,11 @@ radeon_vga_detect(struct drm_connector * enum drm_connector_status ret = connector_status_disconnected; int r; - r = pm_runtime_get_sync(connector->dev->dev); - if (r < 0) - return connector_status_disconnected; + if (!drm_kms_helper_is_poll_worker()) { + r = pm_runtime_get_sync(connector->dev->dev); + if (r < 0) + return connector_status_disconnected; + } encoder = radeon_best_single_encoder(connector); if (!encoder) @@ -1089,8 +1097,10 @@ radeon_vga_detect(struct drm_connector * radeon_connector_update_scratch_regs(connector, ret); out: - pm_runtime_mark_last_busy(connector->dev->dev); - pm_runtime_put_autosuspend(connector->dev->dev); + if (!drm_kms_helper_is_poll_worker()) { + pm_runtime_mark_last_busy(connector->dev->dev); + pm_runtime_put_autosuspend(connector->dev->dev); + } return ret; } @@ -1153,9 +1163,11 @@ radeon_tv_detect(struct drm_connector *c if (!radeon_connector->dac_load_detect) return ret; - r = pm_runtime_get_sync(connector->dev->dev); - if (r < 0) - return connector_status_disconnected; + if (!drm_kms_helper_is_poll_worker()) { + r = pm_runtime_get_sync(connector->dev->dev); + if (r < 0) + return connector_status_disconnected; + } encoder = radeon_best_single_encoder(connector); if (!encoder) @@ -1167,8 +1179,12 @@ radeon_tv_detect(struct drm_connector *c if (ret == connector_status_connected) ret = radeon_connector_analog_encoder_conflict_solve(connector, encoder, ret, false); radeon_connector_update_scratch_regs(connector, ret); - pm_runtime_mark_last_busy(connector->dev->dev); - pm_runtime_put_autosuspend(connector->dev->dev); + + if (!drm_kms_helper_is_poll_worker()) { + pm_runtime_mark_last_busy(connector->dev->dev); + pm_runtime_put_autosuspend(connector->dev->dev); + } + return ret; } @@ -1230,9 +1246,11 @@ radeon_dvi_detect(struct drm_connector * enum drm_connector_status ret = connector_status_disconnected; bool dret = false, broken_edid = false; - r = pm_runtime_get_sync(connector->dev->dev); - if (r < 0) - return connector_status_disconnected; + if (!drm_kms_helper_is_poll_worker()) { + r = pm_runtime_get_sync(connector->dev->dev); + if (r < 0) + return connector_status_disconnected; + } if (radeon_connector->detected_hpd_without_ddc) { force = true; @@ -1415,8 +1433,10 @@ out: } exit: - pm_runtime_mark_last_busy(connector->dev->dev); - pm_runtime_put_autosuspend(connector->dev->dev); + if (!drm_kms_helper_is_poll_worker()) { + pm_runtime_mark_last_busy(connector->dev->dev); + pm_runtime_put_autosuspend(connector->dev->dev); + } return ret; } @@ -1666,9 +1686,11 @@ radeon_dp_detect(struct drm_connector *c if (radeon_dig_connector->is_mst) return connector_status_disconnected; - r = pm_runtime_get_sync(connector->dev->dev); - if (r < 0) - return connector_status_disconnected; + if (!drm_kms_helper_is_poll_worker()) { + r = pm_runtime_get_sync(connector->dev->dev); + if (r < 0) + return connector_status_disconnected; + } if (!force && radeon_check_hpd_status_unchanged(connector)) { ret = connector->status; @@ -1755,8 +1777,10 @@ radeon_dp_detect(struct drm_connector *c } out: - pm_runtime_mark_last_busy(connector->dev->dev); - pm_runtime_put_autosuspend(connector->dev->dev); + if (!drm_kms_helper_is_poll_worker()) { + pm_runtime_mark_last_busy(connector->dev->dev); + pm_runtime_put_autosuspend(connector->dev->dev); + } return ret; }