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29c90bf3e9
After commit c95036feef ("PM / devfreq: rockchip_dmc: Fix deadlock between dmcfreq and vop on/off"),
rockchip_dmcfreq_sem support down read recursive.
Try to avoid lockdep warning:
======================================================
WARNING: possible circular locking dependency detected
4.19.172 #9 Not tainted
------------------------------------------------------
composer@2.1-se/221 is trying to acquire lock:
00000000a1c9588b (&genpd->mlock){+.+.}, at: genpd_lock_mtx+0x14/0x1c
but task is already holding lock:
00000000cc938c9c (rockchip_dmcfreq_sem){++++}, at: rockchip_dmcfreq_lock+0x14/0x1c
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (rockchip_dmcfreq_sem){++++}:
down_read+0x50/0x94
rockchip_dmcfreq_lock+0x14/0x1c
rockchip_pd_power+0x3c/0x200
rockchip_pd_power_off+0x24/0x2c
genpd_power_off+0x168/0x27c
genpd_power_off_work_fn+0x34/0x50
process_one_work+0x300/0x66c
worker_thread+0x238/0x4c0
kthread+0x148/0x158
ret_from_fork+0x10/0x18
-> #1 (&pmu->mutex){+.+.}:
__mutex_lock_common+0xc8/0x1014
mutex_lock_nested+0x28/0x30
rockchip_pd_power+0x38/0x200
rockchip_pd_power_off+0x24/0x2c
genpd_power_off+0x168/0x27c
genpd_power_off_work_fn+0x34/0x50
process_one_work+0x300/0x66c
worker_thread+0x238/0x4c0
kthread+0x148/0x158
ret_from_fork+0x10/0x18
-> #0 (&genpd->mlock){+.+.}:
lock_acquire+0x124/0x1ec
__mutex_lock_common+0xc8/0x1014
mutex_lock_nested+0x28/0x30
genpd_lock_mtx+0x14/0x1c
genpd_runtime_suspend+0x1d8/0x21c
__rpm_callback+0x150/0x24c
rpm_suspend+0x278/0x7b0
rpm_idle+0x6c/0x444
__pm_runtime_idle+0x78/0x9c
vop2_crtc_atomic_disable+0x5ac/0x6b4
drm_atomic_helper_commit_modeset_disables+0x234/0x440
rockchip_atomic_commit_complete+0x140/0x378
rockchip_drm_atomic_commit+0x1c4/0x224
drm_atomic_connector_commit_dpms+0x110/0x128
drm_mode_obj_set_property_ioctl+0x144/0x2b4
drm_connector_property_set_ioctl+0x3c/0x60
drm_ioctl+0x2c0/0x454
do_vfs_ioctl+0x4dc/0x794
__arm64_sys_ioctl+0x70/0x98
el0_svc_common+0x9c/0x16c
el0_svc_handler+0x28/0x60
el0_svc+0x8/0xc
other info that might help us debug this:
Chain exists of:
&genpd->mlock --> &pmu->mutex --> rockchip_dmcfreq_sem
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(rockchip_dmcfreq_sem);
lock(&pmu->mutex);
lock(rockchip_dmcfreq_sem);
lock(&genpd->mlock);
*** DEADLOCK ***
4 locks held by composer@2.1-se/221:
#0: 0000000079852c0e (crtc_ww_class_acquire){+.+.}, at: drm_mode_obj_set_property_ioctl+0xe4/0x2b4
#1: 00000000a8d2d1f1 (crtc_ww_class_mutex){+.+.}, at: drm_modeset_backoff+0x118/0x230
#2: 000000008d649114 (&vop2->vop2_lock){+.+.}, at: vop2_crtc_atomic_disable+0x3c/0x6b4
#3: 00000000cc938c9c (rockchip_dmcfreq_sem){++++}, at: rockchip_dmcfreq_lock+0x14/0x1c
stack backtrace:
CPU: 0 PID: 221 Comm: composer@2.1-se Not tainted 4.19.172 #9
Hardware name: Rockchip RK3566 EVB2 LP4X V10 Board (DT)
Call trace:
dump_backtrace+0x0/0x160
show_stack+0x14/0x1c
dump_stack+0xd8/0x128
print_circular_bug+0x580/0x588
__lock_acquire+0x1bc4/0x1bd0
lock_acquire+0x124/0x1ec
__mutex_lock_common+0xc8/0x1014
mutex_lock_nested+0x28/0x30
genpd_lock_mtx+0x14/0x1c
genpd_runtime_suspend+0x1d8/0x21c
__rpm_callback+0x150/0x24c
rpm_suspend+0x278/0x7b0
rpm_idle+0x6c/0x444
__pm_runtime_idle+0x78/0x9c
vop2_crtc_atomic_disable+0x5ac/0x6b4
drm_atomic_helper_commit_modeset_disables+0x234/0x440
rockchip_atomic_commit_complete+0x140/0x378
rockchip_drm_atomic_commit+0x1c4/0x224
drm_atomic_connector_commit_dpms+0x110/0x128
drm_mode_obj_set_property_ioctl+0x144/0x2b4
drm_connector_property_set_ioctl+0x3c/0x60
drm_ioctl+0x2c0/0x454
do_vfs_ioctl+0x4dc/0x794
__arm64_sys_ioctl+0x70/0x98
el0_svc_common+0x9c/0x16c
el0_svc_handler+0x28/0x60
el0_svc+0x8/0xc
Signed-off-by: Tao Huang <huangtao@rock-chips.com>
Change-Id: Ic743189e335b0e9ae7fed9c3d542bf1d57f5d33a
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