Re: [GIT PULL] x86/urgent for v5.11-rc7

[Andy Lutomirski]

> On Feb 9, 2021, at 10:09 AM, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
> 
> On Tue, Feb 9, 2021 at 8:55 AM Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
>> 
>> Or we hack up #CP to handle this case. I don’t quite know how I feel about this.
> 
> I think that's the sane model - if we've replaced the instruction with
> 'int3', and we end up getting #CP due to that, just do the #BP
> handling.
> 
> Anything else would just be insanely complicated, I feel.

The other model is “don’t do that then.”

I suppose a nice property of patching ENDBR to INT3 is that, not only is it atomic, but ENDBR is sort of a NOP, so we don’t need to replace the ENDBR with anything.

> 
>             Linus