Re: [Qemu-arm] [PATCH RFC 1/8] target-i386: cpu: move features logic that requires CPUState to realize time

[Eduardo Habkost]

On Thu, Jun 02, 2016 at 08:23:37PM +0200, Igor Mammedov wrote:
> On Thu, 2 Jun 2016 14:34:27 -0300
> Eduardo Habkost <address@hidden> wrote:
[...]
> > > > > 
> > > > > I don't plan to replace plus/minus_features with anything nor to
> > > > > make this variables a global ones to spread +- x86/sparc legacy
> > > > > format everywhere.  
> > > > 
> > > > Can't the +/- semantics be emulated by simply registering
> > > > plus_features/minus_features after the other global properties
> > > > are registered inside x86_cpu_parse_featurestr()?
> > > it could be done, at the first glance it will take 2 extra parsing
> > > passes
> > > 
> > > 1: copy featurestr, parse feat=x,feat
> > > 2: copy featurestr, parse +feat
> > > 3: copy featurestr, parse -feat
> > 
> > Why? Can't we just replace plus_features and minus_features with
> > two string lists (or a QDict), and make the corresponding
> > object_property_parse()/qdev_prop_register_global() calls after
> > the main parsing loop?
> > 
> > (Didn't you do that in your old "target-i386: set [+-]feature
> > using static properties" patch?)
> ok, I'll do that.

Thanks!

[...]
> > But as I said above: if we are not deleting any code (and are
> > adding extra code instead), I don't see the point of forcibly
> > disabling it. We can just leave it there and print a warning.
> ok, lets go with warning, saying"
> 
> "[+-]feature syntax is obsoleted and will be removed in future,
> it's recommended to use canonical property syntax 'feature=value'"

We could print "+%s is obsolete [...] use '%s=on'" and
"-%s is obsolete [...] use '%s=off'", depending on the case. This
way, users can see more easily what's the proper syntax.

-- 
Eduardo