diff options
| author | Jesse.Zhang <Jesse.Zhang@amd.com> | 2025-10-24 16:09:25 +0800 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2025-11-11 22:50:22 -0500 |
| commit | 6623c5f9fd877868fba133b4ae4dab0052e82dad (patch) | |
| tree | 256b10f40733c86b45eba3636f6d715c1cf3379f | |
| parent | 9f8fd538e244b87e4556833da51ddd986f50cc81 (diff) | |
| download | net-6623c5f9fd877868fba133b4ae4dab0052e82dad.tar.gz | |
drm/amdgpu: fix lock warning in amdgpu_userq_fence_driver_process
Fix a potential deadlock caused by inconsistent spinlock usage
between interrupt and process contexts in the userq fence driver.
The issue occurs when amdgpu_userq_fence_driver_process() is called
from both:
- Interrupt context: gfx_v11_0_eop_irq() -> amdgpu_userq_fence_driver_process()
- Process context: amdgpu_eviction_fence_suspend_worker() ->
amdgpu_userq_fence_driver_force_completion() -> amdgpu_userq_fence_driver_process()
In interrupt context, the spinlock was acquired without disabling
interrupts, leaving it in {IN-HARDIRQ-W} state. When the same lock
is acquired in process context, the kernel detects inconsistent
locking since the process context acquisition would enable interrupts
while holding a lock previously acquired in interrupt context.
Kernel log shows:
[ 4039.310790] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
[ 4039.310804] kworker/7:2/409 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 4039.310818] ffff9284e1bed000 (&fence_drv->fence_list_lock){?...}-{3:3},
[ 4039.310993] {IN-HARDIRQ-W} state was registered at:
[ 4039.311004] lock_acquire+0xc6/0x300
[ 4039.311018] _raw_spin_lock+0x39/0x80
[ 4039.311031] amdgpu_userq_fence_driver_process.part.0+0x30/0x180 [amdgpu]
[ 4039.311146] amdgpu_userq_fence_driver_process+0x17/0x30 [amdgpu]
[ 4039.311257] gfx_v11_0_eop_irq+0x132/0x170 [amdgpu]
Fix by using spin_lock_irqsave()/spin_unlock_irqrestore() to properly
manage interrupt state regardless of calling context.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jesse Zhang <Jesse.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit ded3ad780cf97a04927773c4600823b84f7f3cc2)
Cc: stable@vger.kernel.org
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c index 761bad98da3ec4..4d0096d0baa9d0 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c @@ -151,15 +151,16 @@ void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_d { struct amdgpu_userq_fence *userq_fence, *tmp; struct dma_fence *fence; + unsigned long flags; u64 rptr; int i; if (!fence_drv) return; + spin_lock_irqsave(&fence_drv->fence_list_lock, flags); rptr = amdgpu_userq_fence_read(fence_drv); - spin_lock(&fence_drv->fence_list_lock); list_for_each_entry_safe(userq_fence, tmp, &fence_drv->fences, link) { fence = &userq_fence->base; @@ -174,7 +175,7 @@ void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_d list_del(&userq_fence->link); dma_fence_put(fence); } - spin_unlock(&fence_drv->fence_list_lock); + spin_unlock_irqrestore(&fence_drv->fence_list_lock, flags); } void amdgpu_userq_fence_driver_destroy(struct kref *ref) |