Hi Vitaly,
On 7/24/2026 3:48 AM, [email protected] wrote:
From: Vitaly Prosyak <[email protected]>
Add ddev->filelist_mutex as level 7 in the lockdep hierarchy, between
reset_lock (level 6) and srbm_mutex (now level 8). This teaches lockdep
the correct ordering for filelist_mutex relative to other amdgpu locks.
The ordering evidence comes from the GPU reset path: gpu_recover() holds
reset_domain->sem (write) and calls amdgpu_device_eventfd_signal_gpu_reset()
which acquires filelist_mutex to iterate the DRM file list and signal
eventfds. This places filelist_mutex inner to reset_domain->sem.
Existing filelist_mutex users (amdgpu_gem_force_release, debugfs vm_info)
do not hold any reset locks, so this ordering is consistent with all
current call paths.
Updated hierarchy (10 lock levels):
1. userq_sch_mutex - Global userq scheduler
2. userq_mutex - Per-context userq
3. notifier_lock - MMU notifier
4. vram_lock - VRAM allocator
5. reset_domain->sem - GPU reset synchronization
6. reset_lock - Reset control
The reset_domain->sem -> filelist_mutex ordering makes sense. But
placing it at level 7 also implies reset_lock -> filelist_mutex — is
there a real path doing that?
Otherwise looks good to me,
Acked-by: Arunpravin Paneer Selvam <[email protected]>
Regards,
Arun.
7. filelist_mutex - DRM file list iteration (NEW)
8. srbm_mutex - SRBM register access
9. grbm_idx_mutex - GRBM index access
10. mmio_idx_lock - MMIO index (spinlock, innermost)
Requested-by: Christian König <[email protected]>
Cc: Christian König <[email protected]>
Cc: Alex Deucher <[email protected]>
Cc: Jesse Zhang <[email protected]>
Cc: Arunpravin PaneerSelvam <[email protected]>
Signed-off-by: Vitaly Prosyak <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_lockdep.c | 29 ++++++++++++++++-----
1 file changed, 22 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_lockdep.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_lockdep.c
index 61450af539a6..b251350b1fb2 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_lockdep.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_lockdep.c
@@ -18,6 +18,7 @@
struct amdgpu_lockdep_dummy_locks {
struct mutex reset_lock;
+ struct mutex filelist_mutex;
struct mutex userq_sch_mutex;
struct mutex userq_mutex;
struct mutex notifier_lock;
@@ -34,6 +35,7 @@ static struct lock_class_key amdgpu_notifier_lock_key;
static struct lock_class_key amdgpu_vram_lock_key;
static struct lock_class_key amdgpu_reset_sem_key;
static struct lock_class_key amdgpu_reset_lock_key;
+static struct lock_class_key amdgpu_filelist_mutex_key;
static struct lock_class_key amdgpu_srbm_lock_key;
static struct lock_class_key amdgpu_grbm_lock_key;
static struct lock_class_key amdgpu_mmio_lock_key;
@@ -57,6 +59,9 @@ void amdgpu_lockdep_set_class(struct amdgpu_device *adev)
if (adev->reset_domain)
lockdep_set_class(&adev->reset_domain->sem,
&amdgpu_reset_sem_key);
+
+ lockdep_set_class(&adev_to_drm(adev)->filelist_mutex,
+ &amdgpu_filelist_mutex_key);
}
/**
@@ -74,9 +79,10 @@ void amdgpu_lockdep_set_class(struct amdgpu_device *adev)
* 4. vram_lock - VRAM allocator lock
* 5. reset_domain->sem - GPU reset synchronization
* 6. reset_lock - Reset control lock
- * 7. srbm_mutex - SRBM register access
- * 8. grbm_idx_mutex - GRBM index access
- * 9. mmio_idx_lock - MMIO index access (spinlock)
+ * 7. filelist_mutex - DRM file list iteration (ddev->filelist_mutex)
+ * 8. srbm_mutex - SRBM register access
+ * 9. grbm_idx_mutex - GRBM index access
+ * 10. mmio_idx_lock - MMIO index access (spinlock)
*
* Evidence:
* - userq_sch_mutex -> userq_mutex: amdgpu_gfx_kfd_sch_ctrl() calls
@@ -88,6 +94,9 @@ void amdgpu_lockdep_set_class(struct amdgpu_device *adev)
* must be outer to reset_domain->sem
* - vram_lock -> reset_domain->sem: VRAM management paths may need to
* wait for ongoing reset to complete
+ * - reset_domain->sem -> filelist_mutex: GPU reset path
+ * (amdgpu_device_gpu_recover) holds reset_domain->sem and calls
+ * amdgpu_device_eventfd_signal_gpu_reset() which takes filelist_mutex
*
* Note: mmap_lock ordering relative to GPU locks is already taught
* by dma-resv (drivers/dma-buf/dma-resv.c).
@@ -117,6 +126,7 @@ int amdgpu_lockdep_init(void)
mutex_init(&locks->notifier_lock);
mutex_init(&locks->vram_lock);
mutex_init(&locks->reset_lock);
+ mutex_init(&locks->filelist_mutex);
mutex_init(&locks->srbm_mutex);
mutex_init(&locks->grbm_idx_mutex);
spin_lock_init(&locks->mmio_idx_lock);
@@ -132,6 +142,7 @@ int amdgpu_lockdep_init(void)
lockdep_set_class(&locks->vram_lock, &amdgpu_vram_lock_key);
lockdep_set_class(&reset_domain->sem, &amdgpu_reset_sem_key);
lockdep_set_class(&locks->reset_lock, &amdgpu_reset_lock_key);
+ lockdep_set_class(&locks->filelist_mutex, &amdgpu_filelist_mutex_key);
lockdep_set_class(&locks->srbm_mutex, &amdgpu_srbm_lock_key);
lockdep_set_class(&locks->grbm_idx_mutex, &amdgpu_grbm_lock_key);
lockdep_set_class(&locks->mmio_idx_lock, &amdgpu_mmio_lock_key);
@@ -154,18 +165,21 @@ int amdgpu_lockdep_init(void)
/* Level 6: Reset control lock */
mutex_lock(&locks->reset_lock);
+
+ /* Level 7: DRM file list mutex */
+ mutex_lock(&locks->filelist_mutex);
/*
* Mark potential memory reclaim boundary.
* GPU operations might trigger memory allocation/reclaim.
*/
fs_reclaim_acquire(GFP_KERNEL);
- /* Level 7: SRBM register access */
+ /* Level 8: SRBM register access */
mutex_lock(&locks->srbm_mutex);
- /* Level 8: GRBM index access */
+ /* Level 9: GRBM index access */
mutex_lock(&locks->grbm_idx_mutex);
- /* Level 9: MMIO index access (innermost lock, spinlock) */
+ /* Level 10: MMIO index access (innermost lock, spinlock) */
spin_lock_irqsave(&locks->mmio_idx_lock, flags);
/*
* All locks acquired in order.
@@ -178,6 +192,7 @@ int amdgpu_lockdep_init(void)
mutex_unlock(&locks->srbm_mutex);
fs_reclaim_release(GFP_KERNEL);
+ mutex_unlock(&locks->filelist_mutex);
mutex_unlock(&locks->reset_lock);
up_read(&reset_domain->sem);
@@ -190,7 +205,7 @@ int amdgpu_lockdep_init(void)
amdgpu_reset_put_reset_domain(reset_domain);
kfree(locks);
- pr_info("AMDGPU: Lockdep annotations initialized (9 lock levels)\n");
+ pr_info("AMDGPU: Lockdep annotations initialized (10 lock levels)\n");
return 0;
}
