Hi Jason, On 11/29/22 09:10, Jason Wang wrote: > Without caching mode, MAP notifier won't work correctly since guest > won't send IOTLB update event when it establishes new mappings in the > I/O page tables. Let's fail the IOMMU notifiers early instead of > misbehaving silently. > > Signed-off-by: Jason Wang <jasow...@redhat.com> Reviewed-by: Eric Auger <eric.au...@redhat.com>
Thanks Eric > --- > hw/i386/intel_iommu.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c > index a08ee85edf..9143376677 100644 > --- a/hw/i386/intel_iommu.c > +++ b/hw/i386/intel_iommu.c > @@ -3186,6 +3186,13 @@ static int > vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu, > "Snoop Control with vhost or VFIO is not > supported"); > return -ENOTSUP; > } > + if (!s->caching_mode && (new & IOMMU_NOTIFIER_MAP)) { > + error_setg_errno(errp, ENOTSUP, > + "device %02x.%02x.%x requires caching mode", > + pci_bus_num(vtd_as->bus), PCI_SLOT(vtd_as->devfn), > + PCI_FUNC(vtd_as->devfn)); > + return -ENOTSUP; > + } > > /* Update per-address-space notifier flags */ > vtd_as->notifier_flags = new;