amdgpu'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 amdgpu'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. Fixes: d38ceaf99ed0 ("drm/amdgpu: add core driver (v4)") Cc: stable@xxxxxxxxxxxxxxx # v4.2+: 1234567890ab: workqueue: Allow retrieval of current task's work struct Cc: stable@xxxxxxxxxxxxxxx # v4.2+: 1234567890ab: drm: Allow determining if current task is output poll worker Cc: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx> --- drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c | 58 +++++++++++++++++--------- 1 file changed, 38 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c index 8ca3783f2deb..74d2efaec52f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c @@ -736,9 +736,11 @@ amdgpu_connector_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 amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(encoder); @@ -757,8 +759,12 @@ amdgpu_connector_lvds_detect(struct drm_connector *connector, bool force) /* check acpi lid status ??? */ amdgpu_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; } @@ -868,9 +874,11 @@ amdgpu_connector_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 = amdgpu_connector_best_single_encoder(connector); if (!encoder) @@ -924,8 +932,10 @@ amdgpu_connector_vga_detect(struct drm_connector *connector, bool force) amdgpu_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; } @@ -988,9 +998,11 @@ amdgpu_connector_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 (!force && amdgpu_connector_check_hpd_status_unchanged(connector)) { ret = connector->status; @@ -1115,8 +1127,10 @@ amdgpu_connector_dvi_detect(struct drm_connector *connector, bool force) amdgpu_connector_update_scratch_regs(connector, ret); 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; } @@ -1359,9 +1373,11 @@ amdgpu_connector_dp_detect(struct drm_connector *connector, bool force) struct drm_encoder *encoder = amdgpu_connector_best_single_encoder(connector); 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 (!force && amdgpu_connector_check_hpd_status_unchanged(connector)) { ret = connector->status; @@ -1429,8 +1445,10 @@ amdgpu_connector_dp_detect(struct drm_connector *connector, bool force) amdgpu_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; } -- 2.15.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx