Re: [PATCH 3/3] drm/amdgpu: Implement bad_page_threshold = -2 case

["Lazar, Lijo" <lijo.lazar@amd.com>]

On 10/20/2021 10:05 PM, Kent Russell wrote:
> If the bad_page_threshold kernel parameter is set to -2,
> continue to post the GPU. Print a warning to dmesg that this action has
> been done, and that page retirement will obviously not work for said GPU
> 
> Cc: Luben Tuikov <luben.tuikov@amd.com>
> Cc: Mukul Joshi <Mukul.Joshi@amd.com>
> Signed-off-by: Kent Russell <kent.russell@amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c | 13 +++++++++----
>   1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c
> index 1ede0f0d6f55..31852330c1db 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c
> @@ -1115,11 +1115,16 @@ int amdgpu_ras_eeprom_init(struct amdgpu_ras_eeprom_control *control,
>   			res = amdgpu_ras_eeprom_correct_header_tag(control,
>   								   RAS_TABLE_HDR_VAL);
>   		} else {
> -			*exceed_err_limit = true;
> -			dev_err(adev->dev,
> -				"RAS records:%d exceed threshold:%d, "
> -				"GPU will not be initialized. Replace this GPU or increase the threshold",
> +			dev_err(adev->dev, "RAS records:%d exceed threshold:%d",
>   				control->ras_num_recs, ras->bad_page_cnt_threshold);
> +			if (amdgpu_bad_page_threshold == -2) {
> +				dev_warn(adev->dev, "GPU will be initialized due to bad_page_threshold = -2.");
> +				dev_warn(adev->dev, "Page retirement will not work for this GPU in this state.");

Now, this looks as good as booting with 0 = disable bad page retirement. 
I thought page retirement will work as long as EEPROM has space, but it 
won't bother about the threshold. If the intent is to ignore bad page 
retirement, then 0 is good enough and -2 is not required.

Also, when user passes threshold=-2, what is the threshold being 
compared against to say *exceed_err_limit = true?

Thanks,
Lijo

> +				res = 0;
> +			} else {
> +				*exceed_err_limit = true;
> +				dev_err(adev->dev, "GPU will not be initialized. Replace this GPU or increase the threshold.");
> +			}
>   		}
>   	} else {
>   		DRM_INFO("Creating a new EEPROM table");
>