Messages in this thread | | | From | Linus Torvalds <> | Date | Wed, 17 Aug 2016 14:35:46 -0700 | Subject | Re: RFC: Petition Intel/AMD to add POPF_IF insn |
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On Wed, Aug 17, 2016 at 2:26 PM, Linus Torvalds <torvalds@linux-foundation.org> wrote: > > Of course, if somebody uses native_restore_fl() to actually *disable* > interrupts (when they weren't already disabled), then this untested > patch will just not work. But why would you do somethign so stupid? > Famous last words...
Looking around, the vsmp code actually uses "native_restore_fl()" to not just set the interrupt flag, but AC as well.
And the PV spinlock case has that "push;popf" sequence encoded in an alternate.
So that trivial patch may (or may not - still not tested) work for some quick testing, but needs more effort for any *real* use.
Linus
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