diff options
author | Lukas Wunner <lukas@wunner.de> | 2018-02-11 10:38:28 +0100 |
---|---|---|
committer | Lukas Wunner <lukas@wunner.de> | 2018-02-16 22:37:27 +0100 |
commit | 15734feff2bdac24aa3266c437cffa42851990e3 (patch) | |
tree | b6946b33b8bd815730b2e2e8fbca98d40598f0b7 /drivers/gpu | |
parent | d61a5c1063515e855bedb1b81e20e50b0ac3541e (diff) |
drm/radeon: Fix deadlock on runtime suspend
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 <ismo.toijala@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Dave Airlie <airlied@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/64ea02c44f91dda19bc563902b97bbc699040392.1518338789.git.lukas@wunner.de
Diffstat (limited to 'drivers/gpu')
-rw-r--r-- | drivers/gpu/drm/radeon/radeon_connectors.c | 74 |
1 files changed, 49 insertions, 25 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c index 59dcefb2df3b..30e129684c7c 100644 --- a/drivers/gpu/drm/radeon/radeon_connectors.c +++ b/drivers/gpu/drm/radeon/radeon_connectors.c @@ -900,9 +900,11 @@ radeon_lvds_detect(struct drm_connector *connector, bool force) 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); @@ -925,8 +927,12 @@ radeon_lvds_detect(struct drm_connector *connector, bool force) /* 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; } @@ -1040,9 +1046,11 @@ radeon_vga_detect(struct drm_connector *connector, bool force) 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) @@ -1109,8 +1117,10 @@ radeon_vga_detect(struct drm_connector *connector, bool force) 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; } @@ -1174,9 +1184,11 @@ radeon_tv_detect(struct drm_connector *connector, bool force) 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) @@ -1188,8 +1200,12 @@ radeon_tv_detect(struct drm_connector *connector, bool force) 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; } @@ -1252,9 +1268,11 @@ radeon_dvi_detect(struct drm_connector *connector, bool force) 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; @@ -1437,8 +1455,10 @@ 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; } @@ -1689,9 +1709,11 @@ radeon_dp_detect(struct drm_connector *connector, bool force) 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; @@ -1778,8 +1800,10 @@ radeon_dp_detect(struct drm_connector *connector, bool force) } 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; } |