On Mon, Jun 26, 2023 at 12:13 PM Viktor Prutyanov <vik...@daynix.com> wrote: > > When IOMMU and vhost are enabled together, QEMU tracks IOTLB or > Device-TLB unmap events depending on whether Device-TLB is enabled. But > 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 series adds checking of ATS state for proper unmap flag register > (IOMMU_NOTIFIER_UNMAP or IOMMU_NOTIFIER_DEVIOTLB_UNMAP). > > Tested on Windows Server 2022, Windows 11 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 > Tested on Fedora guest with > -device virtio-iommu > > Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2001312 > > v5: add vhost_toggle_device_iotlb to vhost-stub > v4: call vhost_toggle_device_iotlb regardless of vhost backend, > move vhost_started check to generic part > v3: call virtio_pci_ats_ctrl_trigger directly, remove > IOMMU_NOTIFIER_UNMAP fallbacks > v2: remove memory_region_iommu_notify_flags_changed, move trigger to > VirtioDeviceClass, use vhost_ops, use device_iotlb name > > Viktor Prutyanov (2): > vhost: register and change IOMMU flag depending on Device-TLB state > virtio-net: pass Device-TLB enable/disable events to vhost > > hw/net/virtio-net.c | 1 + > hw/virtio/vhost-stub.c | 4 ++++ > hw/virtio/vhost.c | 38 ++++++++++++++++++++++++++------------ > include/hw/virtio/vhost.h | 1 + > 4 files changed, 32 insertions(+), 12 deletions(-) > > -- > 2.21.0 >
ping
