On Wed, Jan 10, 2018 at 09:59:01AM +0100, Ingo Molnar wrote: > > * Willy Tarreau <[email protected]> wrote: > > > On Wed, Jan 10, 2018 at 09:01:02AM +0100, Ingo Molnar wrote: > > > > > > * Willy Tarreau <[email protected]> wrote: > > > > > > > [...] If we had "pit_enabled", something like this could be confusing > > > > because > > > > it's not obvious whether this pti_enabled *enforces* PTI or if its > > > > absence > > > > disables it : > > > > > > > > cmpb $0, PER_CPU_VAR(pti_enabled) > > > > jz .Lend\@ > > > > > > The natural sequence would be: > > > > > > cmpb $1, PER_CPU_VAR(pti_enabled) > > > jne .Lend\@ > > > > > > which is not confusing to me at all. > > > > In fact I think I know now why it still poses me a problem : this > > pti_enabled flag alone is not sufficient to enable PTI, it's just part > > of the condition, as another part comes from the X86_FEATURE_PTI flag. > > However, pti_disabled is sufficient to disable PTI so actually its > > effect matches its name (note BTW that I called it "pti_disable" as a > > verb indicating an action -- "I want to disable pti", and not as a past > > form "pti is disabled"). > > If it's a verb then please name it in the proper order, i.e. 'disable_pti'. > > I'm fine with that approach.
OK thanks. Willy
