Re: [PATCH 4/5] KVM: x86: Wrong register masking in 64-bit mode

[Paolo Bonzini]

Il 07/05/2014 16:50, Bandan Das ha scritto:
> > > +static void assign_masked(ulong *dest, ulong src, int bytes)
> > >  {
> > > -	*dest = (*dest & ~mask) | (src & mask);
> > > +	switch (bytes) {
> > > +	case 2:
> > > +		*dest = (u16)src | (*dest & ~0xfffful);
> > > +		break;
> > > +	case 4:
> > > +		*dest = (u32)src;
> > > +		break;
> > > +	case 8:
> > > +		*dest = src;
> > > +		break;
> > > +	default:
> > > +		BUG();
> IIRC, Paolo mentioned that a WARN() is preferable. But I see
> a lot other places where BUG() is called, maybe, he can confirm.

There is really no reason to crash the host for a misused API, so I do 
believe that a WARN() is preferable.

Paolo
--
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/