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
