> 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