Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> writes: > On Sun, Nov 18, 2018 at 2:17 PM Jiri Kosina <jikos@xxxxxxxxxx> wrote: >> Which gets us back to Tim's fixup patch. Do you still prefer the revert, >> given the existence of that? > > I don't think the code needs to be reverted, but the *behavior* of > just unconditionally enabling STIBP needs to be reverted. Actually I think it should be reverted. Yes of course opt-in is needed. But also when you opt-in it doesn't make sense to set STIBP when the sibling is running the same security context, which is actually a common case. So to even use it properly you would need some scheduler support to detect these cases and only enable it then with opt-in. These patches didn't even try to tackle this problem. -Andi
