drm/amdgpu: SRIOV flr_work should take write_lock
authorJingwen Chen <Jingwen.Chen2@amd.com>
Thu, 1 Jul 2021 02:19:17 +0000 (10:19 +0800)
committerAlex Deucher <alexander.deucher@amd.com>
Thu, 8 Jul 2021 19:12:58 +0000 (15:12 -0400)
[Why]
If flr_work takes read_lock, then other threads who takes
read_lock can access hardware when host is doing vf flr.

[How]
flr_work should take write_lock to avoid this case.

Signed-off-by: Jingwen Chen <Jingwen.Chen2@amd.com>
Reviewed-by: Monk Liu <monk.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drivers/gpu/drm/amd/amdgpu/mxgpu_ai.c
drivers/gpu/drm/amd/amdgpu/mxgpu_nv.c

index 3ee4815..ff2307d 100644 (file)
@@ -252,7 +252,7 @@ static void xgpu_ai_mailbox_flr_work(struct work_struct *work)
         * otherwise the mailbox msg will be ruined/reseted by
         * the VF FLR.
         */
-       if (!down_read_trylock(&adev->reset_sem))
+       if (!down_write_trylock(&adev->reset_sem))
                return;
 
        amdgpu_virt_fini_data_exchange(adev);
@@ -268,7 +268,7 @@ static void xgpu_ai_mailbox_flr_work(struct work_struct *work)
 
 flr_done:
        atomic_set(&adev->in_gpu_reset, 0);
-       up_read(&adev->reset_sem);
+       up_write(&adev->reset_sem);
 
        /* Trigger recovery for world switch failure if no TDR */
        if (amdgpu_device_should_recover_gpu(adev)
index 48e588d..9f7aac4 100644 (file)
@@ -273,7 +273,7 @@ static void xgpu_nv_mailbox_flr_work(struct work_struct *work)
         * otherwise the mailbox msg will be ruined/reseted by
         * the VF FLR.
         */
-       if (!down_read_trylock(&adev->reset_sem))
+       if (!down_write_trylock(&adev->reset_sem))
                return;
 
        amdgpu_virt_fini_data_exchange(adev);
@@ -289,7 +289,7 @@ static void xgpu_nv_mailbox_flr_work(struct work_struct *work)
 
 flr_done:
        atomic_set(&adev->in_gpu_reset, 0);
-       up_read(&adev->reset_sem);
+       up_write(&adev->reset_sem);
 
        /* Trigger recovery for world switch failure if no TDR */
        if (amdgpu_device_should_recover_gpu(adev)