Re: [GIT PULL -tip v3] fix 39 'make headers_check' warnings

[Avi Kivity]

Sam Ravnborg wrote:
> > They are.  This bits advertise to userspace what features kvm supports, 
> > both compile- and run-time.
> >     
>
> This is wrong...
> The headers does not change with the kernel configuration and advertising the
> kvm features via a .h file like this is simply plain broken.
>   

Ok.  Don't know why I thought unifdef was supplied with the full 
configuration.

> You cannot assume that the header files are generated with the exact same config
> as used by the running kernel.
>   

This is just for arch specific defines.  I'll move these to asm/kvm.h.

> And userspace has in no way access to the CONFIG_ namespace which is purely kernel-internal.
>
> I cannot see how you have ever seen kcm advertise that for example KVM_CAP_USER_NMI
> equals to 22 because CONFIG_X86 is never (supposed to be) defined in userspace -
> except if you did so yourself by some means.
>   

We did, we ship a hacked-up kvm.h (generated by unifdef) with our userspace.

Thanks for the clarifications, helpful as always.

--
error compiling committee.c: too many arguments to function

--
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/