Hi all,
On Tue, Sep 13, 2022 at 01:55:48PM -0700, Nathan Huckleberry wrote:
> The mode_valid field in drm_connector_helper_funcs is expected to be of
> type:
> enum drm_mode_status (* mode_valid) (struct drm_connector *connector,
> struct drm_display_mode *mode);
>
> The mismatched return type breaks forward edge kCFI since the underlying
> function definition does not match the function hook definition.
>
> The return type of mdp4_lvds_connector_mode_valid 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]>
> ---
> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
> index 7288041dd86a..7444b75c4215 100644
> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
> @@ -56,8 +56,9 @@ static int mdp4_lvds_connector_get_modes(struct drm_connector *connector)
> return ret;
> }
>
> -static int mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
> - struct drm_display_mode *mode)
> +static enum drm_mode_status
> +mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
> + struct drm_display_mode *mode)
> {
> struct mdp4_lvds_connector *mdp4_lvds_connector =
> to_mdp4_lvds_connector(connector);
> --
> 2.37.2.789.g6183377224-goog
>
>
Did this patch get lost somewhere? I do not see it picked up. It is
needed to avoid a new WIP warning from clang for catching these CFI
failures:
drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c:89:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict]
.mode_valid = mdp4_lvds_connector_mode_valid,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
Cheers,
Nathan
On 01/11/2022 01:10, Nathan Chancellor wrote:
> On Tue, Sep 13, 2022 at 01:55:48PM -0700, Nathan Huckleberry wrote:
>> The mode_valid field in drm_connector_helper_funcs is expected to be of
>> type:
>> enum drm_mode_status (* mode_valid) (struct drm_connector *connector,
>> struct drm_display_mode *mode);
>>
>> The mismatched return type breaks forward edge kCFI since the underlying
>> function definition does not match the function hook definition.
>>
>> The return type of mdp4_lvds_connector_mode_valid 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]>
>> ---
>> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c | 5 +++--
>> 1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>> index 7288041dd86a..7444b75c4215 100644
>> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>> @@ -56,8 +56,9 @@ static int mdp4_lvds_connector_get_modes(struct drm_connector *connector)
>> return ret;
>> }
>>
>> -static int mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
>> - struct drm_display_mode *mode)
>> +static enum drm_mode_status
>> +mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
>> + struct drm_display_mode *mode)
>> {
>> struct mdp4_lvds_connector *mdp4_lvds_connector =
>> to_mdp4_lvds_connector(connector);
>> --
>> 2.37.2.789.g6183377224-goog
>>
>>
>
> Did this patch get lost somewhere? I do not see it picked up. It is
> needed to avoid a new WIP warning from clang for catching these CFI
> failures:
>
> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c:89:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict]
> .mode_valid = mdp4_lvds_connector_mode_valid,
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 1 error generated.
It will be picked into 6.1-rc and then propagate through the stable
kernel updates.
Anyway:
Fixes: 3e87599b68e7 ("drm/msm/mdp4: add LVDS panel support")
Reviewed-by: Dmitry Baryshkov <[email protected]>
--
With best wishes
Dmitry
On 10/31/2022 5:24 PM, Dmitry Baryshkov wrote:
> On 01/11/2022 01:10, Nathan Chancellor wrote:
>> On Tue, Sep 13, 2022 at 01:55:48PM -0700, Nathan Huckleberry wrote:
>>> The mode_valid field in drm_connector_helper_funcs is expected to be of
>>> type:
>>> enum drm_mode_status (* mode_valid) (struct drm_connector *connector,
>>> struct drm_display_mode *mode);
>>>
>>> The mismatched return type breaks forward edge kCFI since the underlying
>>> function definition does not match the function hook definition.
>>>
>>> The return type of mdp4_lvds_connector_mode_valid 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]>
>>> ---
>>> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c | 5 +++--
>>> 1 file changed, 3 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>>> b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>>> index 7288041dd86a..7444b75c4215 100644
>>> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>>> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
>>> @@ -56,8 +56,9 @@ static int mdp4_lvds_connector_get_modes(struct
>>> drm_connector *connector)
>>> return ret;
>>> }
>>> -static int mdp4_lvds_connector_mode_valid(struct drm_connector
>>> *connector,
>>> - struct drm_display_mode *mode)
>>> +static enum drm_mode_status
>>> +mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
>>> + struct drm_display_mode *mode)
>>> {
>>> struct mdp4_lvds_connector *mdp4_lvds_connector =
>>> to_mdp4_lvds_connector(connector);
>>> --
>>> 2.37.2.789.g6183377224-goog
>>>
>>>
>>
>> Did this patch get lost somewhere? I do not see it picked up. It is
>> needed to avoid a new WIP warning from clang for catching these CFI
>> failures:
>>
>> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c:89:16: error:
>> incompatible function pointer types initializing 'enum drm_mode_status
>> (*)(struct drm_connector *, struct drm_display_mode *)' with an
>> expression of type 'int (struct drm_connector *, struct
>> drm_display_mode *)'
>> [-Werror,-Wincompatible-function-pointer-types-strict]
>> .mode_valid = mdp4_lvds_connector_mode_valid,
>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> 1 error generated.
>
> It will be picked into 6.1-rc and then propagate through the stable
> kernel updates.
>
> Anyway:
>
> Fixes: 3e87599b68e7 ("drm/msm/mdp4: add LVDS panel support")
> Reviewed-by: Dmitry Baryshkov <[email protected]>
Yes, it was already merged to the -fixes tree and a PR with it was sent
out for 6.1-rc
https://gitlab.freedesktop.org/drm/msm/-/commit/0b33a33bd15d5bab73b87152b220a8d0153a4587
>
>