Re: [PATCH] platform/surface: aggregator: fix a bit test

[Maximilian Luz]

On 4/20/21 10:44 AM, Dan Carpenter wrote:
> The "funcs" variable is a u64.  If "func" is more than 31 then the
> BIT() shift will wrap instead of testing the high bits.
>
> Fixes: c167b9c7e3d6 ("platform/surface: Add Surface Aggregator subsystem")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

Thanks!

Reviewed-by: Maximilian Luz <luzmaximilian@xxxxxxxxx>

> ---
>   drivers/platform/surface/aggregator/controller.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
> index 00e38284885a..69e86cd599d3 100644
> --- a/drivers/platform/surface/aggregator/controller.c
> +++ b/drivers/platform/surface/aggregator/controller.c
> @@ -1040,7 +1040,7 @@ static int ssam_dsm_load_u32(acpi_handle handle, u64 funcs, u64 func, u32 *ret)
>   	union acpi_object *obj;
>   	u64 val;
>   
> -	if (!(funcs & BIT(func)))
> +	if (!(funcs & BIT_ULL(func)))
>   		return 0; /* Not supported, leave *ret at its default value */
>   
>   	obj = acpi_evaluate_dsm_typed(handle, &SSAM_SSH_DSM_GUID,