On Sun, 7 Feb 2021 10:08:11 + (UTC), Christophe Leroy wrote:
> barrier_nospec() in uaccess helpers is there to protect against
> speculative accesses around access_ok().
>
> When using user_access_begin() sequences together with
> unsafe_get_user() like macros, barrier_nospec() is called for
>
barrier_nospec() in uaccess helpers is there to protect against
speculative accesses around access_ok().
When using user_access_begin() sequences together with
unsafe_get_user() like macros, barrier_nospec() is called for
every single read although we know the access_ok() is done
onece.
Since all
