----- On Jul 6, 2018, at 3:35 PM, Mathieu Desnoyers [email protected] wrote:
> ----- On Jul 6, 2018, at 3:31 PM, Linus Torvalds [email protected] > wrote: > >> On Fri, Jul 6, 2018 at 12:23 PM Mathieu Desnoyers >> <[email protected]> wrote: >>> >>> For -rc, I would favor the following simpler approach. Or I could even >>> just use get_user() instead. Thoughts ? >> >> Please just use "get_user()". >> >> In fact, we should be thinking seriosly about just removing >> __get_user() entirely. It's wrong. It optimizes the wrong thing >> entirely. It _used_ to be that the range check was noticeable, and it >> really isn't any more. These days the expensive parts are the SMAP >> costs, and both get_user() and __get_user() have those, except >> get_user() is safer and doesn't waste I$ on inlining the code to >> disable and re-enable SMAP. > > Will do, thanks! Should I change all 4 bytes __get_user()/__put_user() in kernel/rseq.c for get_user()/put_user() to ensure consistency ? Thanks, Mathieu > > Mathieu > > > -- > Mathieu Desnoyers > EfficiOS Inc. > http://www.efficios.com -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com
