radeon: Fix locking in power management paths

The ttm code could take vram_mutex followed by cp_mutex, while the
reclocking code would do the reverse. Hilarity could ensue.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 4 insertions, 14 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
index 7cc54c804cb0..134b19537d11 100644
--- a/drivers/gpu/drm/radeon/radeon_pm.c
+++ b/drivers/gpu/drm/radeon/radeon_pm.c
@@ -61,6 +61,8 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev, int static_switch)
         if (!static_switch)
                 radeon_get_power_state(rdev, rdev->pm.planned_action);
 
+        mutex_lock(&rdev->ddev->struct_mutex);
+        mutex_lock(&rdev->vram_mutex);
         mutex_lock(&rdev->cp.mutex);
 
         /* wait for GPU idle */
@@ -73,8 +75,6 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev, int static_switch)
         rdev->irq.gui_idle = false;
         radeon_irq_set(rdev);
 
-        mutex_lock(&rdev->vram_mutex);
-
         radeon_unmap_vram_bos(rdev);
 
         if (!static_switch) {
@@ -97,8 +97,6 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev, int static_switch)
                 }
         }
 
-        mutex_unlock(&rdev->vram_mutex);
-        
         /* update display watermarks based on new power state */
         radeon_update_bandwidth_info(rdev);
         if (rdev->pm.active_crtc_count)
@@ -107,6 +105,8 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev, int static_switch)
         rdev->pm.planned_action = PM_ACTION_NONE;
 
         mutex_unlock(&rdev->cp.mutex);
+        mutex_unlock(&rdev->vram_mutex);
+        mutex_unlock(&rdev->ddev->struct_mutex);
 }
 
 static ssize_t radeon_get_power_state_static(struct device *dev,
@@ -134,7 +134,6 @@ static ssize_t radeon_set_power_state_static(struct device *dev,
                 return count;
         }
 
-        mutex_lock(&rdev->ddev->struct_mutex);
         mutex_lock(&rdev->pm.mutex);
         if ((ps >= 0) && (ps < rdev->pm.num_power_states) &&
             (cm >= 0) && (cm < rdev->pm.power_state[ps].num_clock_modes)) {
@@ -152,7 +151,6 @@ static ssize_t radeon_set_power_state_static(struct device *dev,
         } else
                 DRM_ERROR("Invalid power state: %d.%d\n\n", ps, cm);
         mutex_unlock(&rdev->pm.mutex);
-        mutex_unlock(&rdev->ddev->struct_mutex);
 
         return count;
 }
@@ -189,13 +187,11 @@ static ssize_t radeon_set_dynpm(struct device *dev,
         } else if (tmp == 1) {
                 if (rdev->pm.num_power_states > 1) {
                         /* enable dynpm */
-                        mutex_lock(&rdev->ddev->struct_mutex);
                         mutex_lock(&rdev->pm.mutex);
                         rdev->pm.state = PM_STATE_PAUSED;
                         rdev->pm.planned_action = PM_ACTION_DEFAULT;
                         radeon_get_power_state(rdev, rdev->pm.planned_action);
                         mutex_unlock(&rdev->pm.mutex);
-                        mutex_unlock(&rdev->ddev->struct_mutex);
                         /* update power mode info */
                         radeon_pm_compute_clocks(rdev);
                         DRM_INFO("radeon: dynamic power management enabled\n");
@@ -318,11 +314,9 @@ void radeon_pm_fini(struct radeon_device *rdev)
                    (rdev->pm.current_clock_mode_index != 0)) {
                 rdev->pm.requested_power_state_index = rdev->pm.default_power_state_index;
                 rdev->pm.requested_clock_mode_index = 0;
-                mutex_lock(&rdev->ddev->struct_mutex);
                 mutex_lock(&rdev->pm.mutex);
                 radeon_pm_set_clocks(rdev, true);
                 mutex_unlock(&rdev->pm.mutex);
-                mutex_unlock(&rdev->ddev->struct_mutex);
         }
 
         device_remove_file(rdev->dev, &dev_attr_power_state);
@@ -341,7 +335,6 @@ void radeon_pm_compute_clocks(struct radeon_device *rdev)
         if (rdev->pm.state == PM_STATE_DISABLED)
                 return;
 
-        mutex_lock(&rdev->ddev->struct_mutex);
         mutex_lock(&rdev->pm.mutex);
 
         rdev->pm.active_crtcs = 0;
@@ -392,7 +385,6 @@ void radeon_pm_compute_clocks(struct radeon_device *rdev)
         }
 
         mutex_unlock(&rdev->pm.mutex);
-        mutex_unlock(&rdev->ddev->struct_mutex);
 }
 
 bool radeon_pm_debug_check_in_vbl(struct radeon_device *rdev, bool finish)
@@ -468,7 +460,6 @@ static void radeon_pm_idle_work_handler(struct work_struct *work)
                                 pm.idle_work.work);
 
         resched = ttm_bo_lock_delayed_workqueue(&rdev->mman.bdev);
-        mutex_lock(&rdev->ddev->struct_mutex);
         mutex_lock(&rdev->pm.mutex);
         if (rdev->pm.state == PM_STATE_ACTIVE) {
                 unsigned long irq_flags;
@@ -513,7 +504,6 @@ static void radeon_pm_idle_work_handler(struct work_struct *work)
                 }
         }
         mutex_unlock(&rdev->pm.mutex);
-        mutex_unlock(&rdev->ddev->struct_mutex);
         ttm_bo_unlock_delayed_workqueue(&rdev->mman.bdev, resched);
 
         queue_delayed_work(rdev->wq, &rdev->pm.idle_work,