Re: [PATCH] alloc_tag: avoid implicit padding in uapi

[Hao Ge]

On 2026/9/16 04:23, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> The impliied padding causes a harmless warning when testing the uapi
> headers with -Wpadded that could in theory indicate incompatibilies or
> data leaks:
> 
> ./usr/include/linux/alloc_tag.h:41:1: error: padding struct size to alignment boundary with 7 bytes [-Werror=padded]
> 
> The code here is fine, but it's better to make the padding explicit
> and avoid the warning here.
> 
> Fixes: 1d581ab2348c ("alloc_tag: add ioctl to /proc/allocinfo")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Thanks for the fix, with the nit from SJ.
Acked-by: Hao Ge <hao.ge@xxxxxxxxx>

Thanks
Best Regards
Hao

> ---
>  include/uapi/linux/alloc_tag.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/include/uapi/linux/alloc_tag.h b/include/uapi/linux/alloc_tag.h
> index e3ad94444864..7d4618bea043 100644
> --- a/include/uapi/linux/alloc_tag.h
> +++ b/include/uapi/linux/alloc_tag.h
> @@ -38,6 +38,7 @@ struct allocinfo_counter {
>  	__u64 bytes;
>  	__u64 calls;
>  	__u8 accurate;
> +	__u8 pad[7];
>  } __attribute__((aligned(8)));
>  
>  struct allocinfo_tag_data {