Re: [Qemu-devel] [V6 2/4] hw/core: Add AMD IOMMU to machine properties

[David Kiarie]

On 21/02/16 23:09, Jan Kiszka wrote:
> On 2016-02-21 19:10, David Kiarie wrote:
> > diff --git a/qemu-options.hx b/qemu-options.hx
> > index 2f0465e..dad160f 100644
> > --- a/qemu-options.hx
> > +++ b/qemu-options.hx
> > @@ -38,7 +38,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
> >       "                kvm_shadow_mem=size of KVM shadow MMU\n"
> >       "                dump-guest-core=on|off include guest memory in a core dump 
> > (default=on)\n"
> >       "                mem-merge=on|off controls memory merge support (default: 
> > on)\n"
> > -    "                iommu=on|off controls emulated Intel IOMMU (VT-d) support 
> > (default=off)\n"
> > +    "                iommu=amd|intel enables and selects the emulated IOMMU 
> > (default: off)\n"
> We should also support "iommu=off" or "none" to explicitly disable it.
> That is consistent with other switches, and maybe there will once be a
> machine type (chipset) with IOMMU enabled by default.

We could have such but this will not be referenced anywhere in the code 
as the IOMMU is 'off' by default. Most of the other such switches relate 
to properties that are 'on' by default.

> Jan