2022-09-13 23:22:33

by Nathan Chancellor

Subject: Re: [PATCH] drm/i915: Fix return type of mode_valid function hook

On Tue, Sep 13, 2022 at 01:55:27PM -0700, Nathan Huckleberry wrote:
> All of the functions used for intel_dvo_dev_ops.mode_valid have a return
> type of enum drm_mode_status, but the mode_valid field in the struct
> definition has a return type of int.
>
> The mismatched return type breaks forward edge kCFI since the underlying
> function definitions do not match the function hook definition.
>
> The return type of the mode_valid field should be changed from int to
> enum drm_mode_status.
>
> Reported-by: Dan Carpenter <[email protected]>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1703
> Cc: [email protected]
> Signed-off-by: Nathan Huckleberry <[email protected]>

Reviewed-by: Nathan Chancellor <[email protected]>

> ---
> drivers/gpu/drm/i915/display/intel_dvo_dev.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dvo_dev.h b/drivers/gpu/drm/i915/display/intel_dvo_dev.h
> index d96c3cc46e50..50205f064d93 100644
> --- a/drivers/gpu/drm/i915/display/intel_dvo_dev.h
> +++ b/drivers/gpu/drm/i915/display/intel_dvo_dev.h
> @@ -75,8 +75,8 @@ struct intel_dvo_dev_ops {
> *
> * \return MODE_OK if the mode is valid, or another MODE_* otherwise.
> */
> - int (*mode_valid)(struct intel_dvo_device *dvo,
> - struct drm_display_mode *mode);
> + enum drm_mode_status (*mode_valid)(struct intel_dvo_device *dvo,
> + struct drm_display_mode *mode);
>
> /*
> * Callback for preparing mode changes on an output
> --
> 2.37.2.789.g6183377224-goog
>

2022-09-15 08:00:12

by Jani Nikula

Subject: Re: [PATCH] drm/i915: Fix return type of mode_valid function hook

On Tue, 13 Sep 2022, Nathan Chancellor <[email protected]> wrote:
> On Tue, Sep 13, 2022 at 01:55:27PM -0700, Nathan Huckleberry wrote:
>> All of the functions used for intel_dvo_dev_ops.mode_valid have a return
>> type of enum drm_mode_status, but the mode_valid field in the struct
>> definition has a return type of int.
>>
>> The mismatched return type breaks forward edge kCFI since the underlying
>> function definitions do not match the function hook definition.
>>
>> The return type of the mode_valid field should be changed from int to
>> enum drm_mode_status.
>>
>> Reported-by: Dan Carpenter <[email protected]>
>> Link: https://github.com/ClangBuiltLinux/linux/issues/1703
>> Cc: [email protected]
>> Signed-off-by: Nathan Huckleberry <[email protected]>
>
> Reviewed-by: Nathan Chancellor <[email protected]>

Thanks for the patch and reviews, pushed to drm-intel-next.

BR,
Jani.

>
>> ---
>> drivers/gpu/drm/i915/display/intel_dvo_dev.h | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_dvo_dev.h b/drivers/gpu/drm/i915/display/intel_dvo_dev.h
>> index d96c3cc46e50..50205f064d93 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dvo_dev.h
>> +++ b/drivers/gpu/drm/i915/display/intel_dvo_dev.h
>> @@ -75,8 +75,8 @@ struct intel_dvo_dev_ops {
>> *
>> * \return MODE_OK if the mode is valid, or another MODE_* otherwise.
>> */
>> - int (*mode_valid)(struct intel_dvo_device *dvo,
>> - struct drm_display_mode *mode);
>> + enum drm_mode_status (*mode_valid)(struct intel_dvo_device *dvo,
>> + struct drm_display_mode *mode);
>>
>> /*
>> * Callback for preparing mode changes on an output
>> --
>> 2.37.2.789.g6183377224-goog
>>

--
Jani Nikula, Intel Open Source Graphics Center