From: Jason Wang <jasow...@redhat.com>
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.
Reviewed-by: Eric Auger <eric.au...@redhat.com>
Tested-by: Viktor Prutyanov <vik...@daynix.com>
Signed-off-by: Jason Wang <jasow...@redhat.com>
Message-Id: <20230223065924.42503-2-jasow...@redhat.com>
Reviewed-by: Peter Xu <pet...@redhat.com>
Reviewed-by: Michael S. Tsirkin <m...@redhat.com>
Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
(cherry picked from commit b8d78277c091f26fdd64f239bc8bb7e55d74cecf)
Signed-off-by: Michael Tokarev <m...@tls.msk.ru>
---
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;
--
2.30.2
