On Mon, Jun 29, 2026 at 5:50 AM H. Peter Anvin <[email protected]> wrote: > > On 2026-06-28 21:43, Matthew Wilcox wrote: > > On Sun, Jun 28, 2026 at 07:09:37PM -0700, H. Peter Anvin wrote: > >> > >>> 2) `enter` is not rare since we can take part in the instruction. > >> > >> This sentence doesn't parse. > > > > They mean that we can jump into the middle of an instruction, and it is > > not rare to see a 'c8' byte in the instruction stream. > > > > OK, I see the point now. The main difference is that ENTER doesn't require a > REX prefix, whereas ADD/SUB/LEA do (otherwise it truncates RSP and everything > immediately dies as a result of SMAP violations [you are welcome].) >
Yes, Matthew's explanation is correct. (Btw, thanks Matthew!) Xiang > This means that an offending bit combination is far less common. > > -hpa >
