From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([213.167.242.64]:43802 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729770AbeGMQRQ (ORCPT ); Fri, 13 Jul 2018 12:17:16 -0400 Reply-To: kieran.bingham@ideasonboard.com To: Linux Media Mailing List , Linux-Renesas , Laurent Pinchart From: Kieran Bingham Subject: rcar-du/vsp1: possible recursive locking detected Message-ID: <97d625f6-9eb5-d08a-0222-f1cb244f5089@ideasonboard.com> Date: Fri, 13 Jul 2018 17:01:55 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org List-ID: Observing this on linux-media/master branch, while running a simple kmstest with dual outputs (HDMI, VGA) Just reporting for the moment. We'll have to look at bisecting to see if it was introduced recently. [ 31.644076] ============================================ [ 31.649412] WARNING: possible recursive locking detected [ 31.654752] 4.18.0-rc2-arm64-renesas-12862-g666e994aa227 #25 Not tainted [ 31.661483] -------------------------------------------- [ 31.666818] kmstest/986 is trying to acquire lock: [ 31.671631] 000000008bb5ef8e (&vsp1->drm->lock){+.+.}, at: vsp1_du_setup_lif+0x90/0x438 [ 31.679693] [ 31.679693] but task is already holding lock: [ 31.685551] 00000000ef2edc5c (&vsp1->drm->lock){+.+.}, at: vsp1_du_atomic_begin+0x1c/0x28 [ 31.693775] [ 31.693775] other info that might help us debug this: [ 31.700331] Possible unsafe locking scenario: [ 31.700331] [ 31.706276] CPU0 [ 31.708731] ---- [ 31.711185] lock(&vsp1->drm->lock); [ 31.714864] lock(&vsp1->drm->lock); [ 31.718543] [ 31.718543] *** DEADLOCK *** [ 31.718543] [ 31.724489] May be due to missing lock nesting notation [ 31.724489] [ 31.731308] 3 locks held by kmstest/986: [ 31.735246] #0: 0000000073af26f9 (crtc_ww_class_acquire){+.+.}, at: drm_mode_atomic_ioctl+0xa0/0xa50 [ 31.744523] #1: 000000007a933c3a (crtc_ww_class_mutex){+.+.}, at: drm_modeset_lock+0x64/0x118 [ 31.753184] #2: 00000000ef2edc5c (&vsp1->drm->lock){+.+.}, at: vsp1_du_atomic_begin+0x1c/0x28 [ 31.761844] [ 31.761844] stack backtrace: [ 31.766223] CPU: 1 PID: 986 Comm: kmstest Not tainted 4.18.0-rc2-arm64-renesas-12862-g666e994aa227 #25 [ 31.775571] Hardware name: Renesas Salvator-X 2nd version board based on r8a7795 ES2.0+ (DT) [ 31.784047] Call trace: [ 31.786509] dump_backtrace+0x0/0x1c8 [ 31.790187] show_stack+0x14/0x20 [ 31.793521] dump_stack+0xbc/0xf4 [ 31.796853] __lock_acquire+0x964/0x1888 [ 31.800792] lock_acquire+0x48/0x64 [ 31.804297] __mutex_lock+0x70/0x838 [ 31.807887] mutex_lock_nested+0x1c/0x28 [ 31.811826] vsp1_du_setup_lif+0x90/0x438 [ 31.815856] rcar_du_vsp_enable+0x108/0x138 [ 31.820057] rcar_du_crtc_setup+0x3d8/0x548 [ 31.824258] rcar_du_crtc_atomic_begin+0x5c/0x70 [ 31.828899] drm_atomic_helper_commit_planes+0x70/0x208 [ 31.834147] rcar_du_atomic_commit_tail+0x30/0x68 [ 31.838871] commit_tail+0x44/0x78 [ 31.842287] drm_atomic_helper_commit+0xe8/0x160 [ 31.846925] drm_atomic_commit+0x48/0x58 [ 31.850865] drm_mode_atomic_ioctl+0x850/0xa50 [ 31.855328] drm_ioctl_kernel+0x88/0x108 [ 31.859267] drm_ioctl+0x1b8/0x400 [ 31.862686] do_vfs_ioctl+0xb8/0xa20 [ 31.866276] ksys_ioctl+0x44/0x90 [ 31.869605] sys_ioctl+0xc/0x18 [ 31.872759] el0_svc_naked+0x30/0x34 -- Regards -- Kieran