On Fri, Dec 2, 2022 at 12:03 AM Peter Xu <pet...@redhat.com> wrote: > > On Tue, Nov 29, 2022 at 04:10:36PM +0800, Jason Wang wrote: > > Without dt mode, device IOTLB notifier won't work since guest won't > > send device IOTLB invalidation descriptor in this case. Let's fail > > early instead of misbehaving silently. > > > > Signed-off-by: Jason Wang <jasow...@redhat.com> > > --- > > hw/i386/intel_iommu.c | 8 ++++++++ > > 1 file changed, 8 insertions(+) > > > > diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c > > index 9143376677..d025ef2873 100644 > > --- a/hw/i386/intel_iommu.c > > +++ b/hw/i386/intel_iommu.c > > @@ -3179,6 +3179,7 @@ static int > > vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu, > > { > > VTDAddressSpace *vtd_as = container_of(iommu, VTDAddressSpace, iommu); > > IntelIOMMUState *s = vtd_as->iommu_state; > > + X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s); > > > > /* TODO: add support for VFIO and vhost users */ > > if (s->snoop_control) { > > @@ -3193,6 +3194,13 @@ static int > > vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu, > > PCI_FUNC(vtd_as->devfn)); > > return -ENOTSUP; > > } > > + if (!x86_iommu->dt_supported && (new & IOMMU_NOTIFIER_DEVIOTLB_UNMAP)) > > { > > + error_setg_errno(errp, ENOTSUP, > > + "device %02x.%02x.%x requires device IOTLB mode", > > + pci_bus_num(vtd_as->bus), PCI_SLOT(vtd_as->devfn), > > + PCI_FUNC(vtd_as->devfn)); > > + return -ENOTSUP; > > + } > > While my r-b holds.. let's also do this for amd-iommu in the same patch? > dt never supported there, so we can fail as long as DEVIOTLB registered.
Looks like there's one implementation: Per spec: "" The INVALIDATE_IOTLB_PAGES command is only present in IOMMU implementations that support remote IOTLB caching of translations (see Capability Offset 00h[IotlbSup]). This command instructs the specified device to invalidate the given range of addresses in its IOTLB. The size of the invalidate command is determined by the S bit and the address. "" And it has one implementation (though buggy) iommu_inval_iotlb() which doesn't trigger any DEVIOTLB_UNMAP notifier. We can leave this for the future. (Last time I tried amd-iommu it didn't even boot). Thanks > > > > > /* Update per-address-space notifier flags */ > > vtd_as->notifier_flags = new; > > -- > > 2.25.1 > > > > -- > Peter Xu >