On Thu, Jan 11, 2018 at 10:23 AM, David Woodhouse <[email protected]> wrote: > On Thu, 2018-01-11 at 10:22 -0500, Brian Gerst wrote: >> On Thu, Jan 11, 2018 at 9:32 AM, Peter Zijlstra <[email protected]> wrote: >> > On Thu, Jan 11, 2018 at 02:28:32PM +0000, David Woodhouse wrote: >> >> On Thu, 2018-01-11 at 08:20 -0600, Josh Poimboeuf wrote: >> >> > >> >> > This seems weird. I liked v1 a lot better. What's the problem with >> >> > patching in the whole thing? >> >> > >> >> > Also, if you go back to v1, it should be an easy objtool fix, just add >> >> > ANNOTATE_NOSPEC_ALTERNATIVE in front of it. >> >> >> >> The objection was that I was patching in a fairly long set of >> >> instructions. I confess I don't actually know why that's a problem, >> > >> > You get a giant string of NOPs, a single jmp should be faster. >> >> That could be handled in add_nops(), where if over a certain threshold >> it changes to a JMP. > > Currently that only processes the *altinstr* doesn't it? Not the > oldinstr?
It does both. -- Brian Gerst
