Re: [PATCHv3 2/3] kernel: add support for live patching

[Josh Poimboeuf]

On Fri, Nov 21, 2014 at 04:27:57PM +0100, Jiri Kosina wrote:
> On Fri, 21 Nov 2014, Josh Poimboeuf wrote:
> 
> > I think we can use "depends on HAVE_FENTRY" to accomplish this, since 
> > CC_USING_FENTRY gets set by the top level kernel Makefile if 
> > CONFIG_HAVE_FENTRY is set.
> 
> The problem is that HAVE_FENTRY is set automatically on x86_64, no matter 
> whether your actual compiler supports it or not.
> 
> CC_USING_FENTRY is defined if and only if the actual currently used 
> compiler supports it, but that can't be expressed in Kconfig.

Ah, light bulb moment.  Now I understand what "$(call cc-option, ...)"
does.

Thanks :-)

-- 
Josh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/