diff --git a/OvmfPkg/VirtioRngDxe/VirtioRng.c b/OvmfPkg/VirtioRngDxe/VirtioRng.c index d916534aac..1a186d0408 100644 --- a/OvmfPkg/VirtioRngDxe/VirtioRng.c +++ b/OvmfPkg/VirtioRngDxe/VirtioRng.c @@ -242,6 +242,19 @@ VirtioRngInit ( goto Failed; } + Features &= VIRTIO_F_VERSION_1; + + // + // In virtio-1.0, feature negotiation is expected to complete before queue + // discovery, and the device can also reject the selected set of features. + // + if (Dev->VirtIo->Revision >= VIRTIO_SPEC_REVISION (1, 0, 0)) { + Status = Virtio10WriteFeatures (Dev->VirtIo, Features, &NextDevStat); + if (EFI_ERROR (Status)) { + goto Failed; + } + } + // // step 4b -- allocate request virtqueue, just use #0 // @@ -290,14 +303,14 @@ VirtioRngInit ( } // - // step 5 -- Report understood features and guest-tuneables. None are - // currently defined for VirtioRng, and no generic features are needed by - // this driver. + // step 5 -- Report understood features and guest-tuneables. // - Features &= 0; - Status = Dev->VirtIo->SetGuestFeatures (Dev->VirtIo, Features); - if (EFI_ERROR (Status)) { - goto ReleaseQueue; + if (Dev->VirtIo->Revision < VIRTIO_SPEC_REVISION (1, 0, 0)) { + Features &= ~(UINT64)VIRTIO_F_VERSION_1; + Status = Dev->VirtIo->SetGuestFeatures (Dev->VirtIo, Features); + if (EFI_ERROR (Status)) { + goto ReleaseQueue; + } } //