Even if Device-TLB and PCI ATS is enabled, the guest can reject to use it. For example, this situation appears when Windows Server 2022 is running with intel-iommu with device-iotlb=on and virtio-net-pci with vhost=on. The guest implies that no address translation info cached in device IOTLB and doesn't send device IOTLB invalidation commands. So, it leads to irrelevant address translations in vhost-net in the host kernel. Therefore network frames from the guest in host tap interface contains wrong payload data.
This patch enables IOTLB unmap events (IOMMU_NOTIFIER_UNMAP) along with Device-TLB unmap events (IOMMU_NOTIFIER_DEVIOTLB_UNMAP) handling for proper vhost IOTLB unmapping when the guest isn't aware of Device-TLB. Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2001312 Signed-off-by: Viktor Prutyanov <vik...@daynix.com> --- Tested on Windows Server 2022 and Fedora guests with -device virtio-net-pci,bus=pci.3,netdev=nd0,iommu_platform=on,ats=on -netdev tap,id=nd0,ifname=tap1,script=no,downscript=no,vhost=on -device intel-iommu,intremap=on,eim=on,device-iotlb=on/off hw/virtio/vhost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index a266396576..968ca18fce 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -796,7 +796,7 @@ static void vhost_iommu_region_add(MemoryListener *listener, iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, MEMTXATTRS_UNSPECIFIED); iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, - IOMMU_NOTIFIER_DEVIOTLB_UNMAP, + IOMMU_NOTIFIER_DEVIOTLB_UNMAP | IOMMU_NOTIFIER_UNMAP, section->offset_within_region, int128_get64(end), iommu_idx); -- 2.35.1
