Re: [PATCH 06/18] x86, barrier: stop speculation for failed access_ok

Willy Tarreau
2018-01-07T20:12:11Z

On Sun, Jan 07, 2018 at 11:47:07AM -0800, Linus Torvalds wrote:
> And the whole "normal people won't even notice" is pure garbage too.
> Don't spread that bullshit when you see actual normal people
> complaining.
>
> Performance matters. A *LOT*.

Linus, no need to explain that to me, I'm precisely trying to see how
to disable PTI for a specific process because I face up to 45% loss in
certain circumstances, making it a no-go. But while a few of us have
very specific workloads emphasizing this impact, others have very
different ones and will not notice. For example my laptop did boot
pretty fine and I didn't notice anything until I fire a network
benchmark.

Willy