Re: [PATCH] Release the mutex hold before backtracing for not supported mxgpu.

[Christian König]

Am 20.12.2017 um 03:44 schrieb Yu, Xiangliang:

This patch releases the mutex held soon before entering the initialization
function in case the device doesn't support mxgpu.

Signed-off-by: José Pekkarinen 
---
  drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c | 1 +
  1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
b/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
index c25a831f94ec..cac1d8b003e6 100644
--- a/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
+++ b/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
@@ -307,6 +307,7 @@ void xgpu_vi_init_golden_registers(struct
amdgpu_device *adev)

xgpu_tonga_golden_common_all));
break;
default:
+   mutex_unlock(>grbm_idx_mutex);
BUG_ON("Doesn't support chip type.\n");
break;
}

The release mutex in here has no meaning as kernel will hang later.


A BUG_ON() results in killing the current process/thread. That usually 
results in a kernel hang *BECAUSE* you usually don't cleanly unlock all 
the taken locks.


So this patch is actually the first step on cleaning up the code.

BTW: Also please use BUG() + comment instead of BUG_ON() with a fixed text.

Thanks,
Christian.


And Alex has submitted patch to check ASIC IP during detecting SRIOV, so we 
can't see the case anymore. Please drop the patch.

Thanks!


--
2.13.6

___
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx

___
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx


___
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx

RE: [PATCH] Release the mutex hold before backtracing for not supported mxgpu.

[Yu, Xiangliang]

> This patch releases the mutex held soon before entering the initialization
> function in case the device doesn't support mxgpu.
> 
> Signed-off-by: José Pekkarinen 
> ---
>  drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
> b/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
> index c25a831f94ec..cac1d8b003e6 100644
> --- a/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
> +++ b/drivers/gpu/drm/amd/amdgpu/mxgpu_vi.c
> @@ -307,6 +307,7 @@ void xgpu_vi_init_golden_registers(struct
> amdgpu_device *adev)
> 
> xgpu_tonga_golden_common_all));
>   break;
>   default:
> + mutex_unlock(>grbm_idx_mutex);
>   BUG_ON("Doesn't support chip type.\n");
>   break;
>   }

The release mutex in here has no meaning as kernel will hang later. And Alex 
has submitted patch to check ASIC IP during detecting SRIOV, so we can't see 
the case anymore. Please drop the patch.

Thanks!

> --
> 2.13.6
> 
> ___
> amd-gfx mailing list
> amd-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
___
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx