Messages in this thread | | | From | Andy Lutomirski <> | Date | Fri, 4 Dec 2015 14:34:52 -0800 | Subject | Re: [Patch V0] x86, mce: Ensure offline CPU's don't participate in mce rendezvous process. |
| |
On Fri, Dec 4, 2015 at 9:53 AM, Luck, Tony <tony.luck@intel.com> wrote: >> I don't mean that - I mean the stuff we do before we call >> cpu_is_offline() like ist_enter, this_cpu_inc(mce_exception_count), >> etc. Then we do a whole another bunch of stuff at the "out:" label like >> printk and whatnot which shouldn't run on an offlined CPU. > > ist_enter() is black magic to me. Andy? Would you be worried about executing > ist_{enter,exit}() on a cpu that was once online, but is currently marked offline > by Linux?
Offline CPUs are black magic to me. But as long as the CPU works the way that the normal specs say it should, then ist_enter is fair game. In any event, if context tracking blows up on an offline CPU, I'd argue that's a context tracking bug and needs to be fixed.
But maybe offlined CPUs are supposed to have all interrupts off (including MCE?) and the argument goes the other way? Dunno.
--Andy
| |