Re: [patch V3 05/11] x86/mm/cpa: Add debug mechanism

[Peter Zijlstra]

On Fri, Sep 21, 2018 at 09:40:36AM -0700, Dave Hansen wrote:
> On 09/17/2018 07:29 AM, Thomas Gleixner wrote:
> > The whole static protection magic is silently fixing up anything which is
> > handed in. That's just wrong. The offending call sites need to be fixed.
> > 
> > Add a debug mechanism which emits a warning if a requested mapping needs to be
> > fixed up. The DETECT debug mechanism is really not meant to be enabled except
> > for developers, so limit the output hard to the protection fixups.
> ...
> > +enum cpa_warn {
> > +	CPA_PROTECT,
> > +	CPA_DETECT,
> > +};
> > +
> > +static const int cpa_warn_level = CPA_PROTECT;
> 
> Even if this is intended for developers only, should we also add some
> config option here so things like 0day can still get warnings out of this?
> 
> Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxx>

OTOH, I really wish there was something like: depends !RANDCONFIG
for some of those things, because I triggered
GCC_PLUGIN_STRUCTLEAK_VERBOSE in a randconfig the other day and thought
everything was busted due to the massive output.