Re: [RFC PATCH 00/16] x86/split_lock: Enable #AC exception for split locked accesses

From: Thomas Gleixner
Date: Fri Jun 22 2018 - 05:28:32 EST


On Thu, 21 Jun 2018, Fenghua Yu wrote:
> The control knob for firmware is to choose continuing firmware execution
> by disabling #AC split lock (default) or stopping firmware execution
> by enabling #AC for split lock. Stopping firmware execution may be useful
> in hard real time system to identify any split lock issue on the platform.

There is no maybe on a real-time system. Either the thing is sane or it's
not. There is no middle ground. The default has to be fail otherwise
firmware wont be fixed ever.

> So the control knobs may be useful for different scenarios, right?

The control knobs are just helping to proliferate crap, so they are not
useful, they are outright counterproductive.

Thanks,

tglx