Re: SLAB_TYPESAFE_BY_RCU without constructors (was Re: [PATCH v4 13/17] khwasan: add hooks implementation)

[Eric Dumazet]

On Tue, Jul 31, 2018 at 10:51 AM Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:
>
>
> Is it OK to overwrite ct->status? It seems that are some read and
> writes to it right after atomic_inc_not_zero.

If it is after a (successful) atomic_inc_not_zero(),
the object is guaranteed to be alive (not freed or about to be freed).

About readind/writing a specific field, all traditional locking rules apply.

For TCP socket, we would generally grab the socket lock before
reading/writing various fields.

ct->status seems to be manipulated with set_bit() and clear_bit()
which are SMP safe.