Re: [PATCH net-next v4 3/3] eventpoll: Add epoll ioctl for epoll_params

Joe Damato
2024-01-31T02:28:02Z

On Tue, Jan 30, 2024 at 06:08:36PM -0800, Greg Kroah-Hartman wrote:
> On Wed, Jan 31, 2024 at 01:47:33AM +0000, Joe Damato wrote:
> > +struct epoll_params {
> > + __aligned_u64 busy_poll_usecs;
> > + __u16 busy_poll_budget;
> > +
> > + /* pad the struct to a multiple of 64bits for alignment on all arches */
> > + __u8 __pad[6];
>
> You HAVE to check this padding to be sure it is all 0, otherwise it can
> never be used in the future for anything.

Is there some preferred mechanism for this in the kernel that I should be
using or is this as simple as adding a for loop to check each u8 == 0 ?

Thanks.