From 35ffe28a91a2ef08dd181d1a22695050ccbb6995 Mon Sep 17 00:00:00 2001
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Date: Mon, 9 Jan 2023 16:04:43 +0000
Subject: [PATCH 1/2] virtio-rng-pci: fix migration compat for vectors

RH-Author: Dr. David Alan Gilbert <dgilbert@redhat.com>
RH-MergeRequest: 131: virtio-rng-pci: fix migration compat for vectors
RH-Bugzilla: 2155749
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Commit: [1/1] 1a866491dd191b073d71ae1aa5f4d76ee885de6d (dagrh/c-9-s-qemu-kvm)

Fixup the migration compatibility for existing machine types
so that they do not enable msi-x.

Symptom:

(qemu) qemu: get_pci_config_device: Bad config data: i=0x34 read: 84 device: 98 cmask: ff wmask: 0 w1cmask:0
qemu: Failed to load PCIDevice:config
qemu: Failed to load virtio-rng:virtio
qemu: error while loading state for instance 0x0 of device '0000:00:03.0/virtio-rng'
qemu: load of migration failed: Invalid argument

Note: This fix will break migration from 7.2->7.2-fixed with this patch

bz: https://bugzilla.redhat.com/show_bug.cgi?id=2155749
Fixes: 9ea02e8f1 ("virtio-rng-pci: Allow setting nvectors, so we can use MSI-X")

This downstream fix is the equivalent of an upstream fix I've posted to
the 7.2 machine type compatibility.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 hw/core/machine.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/hw/core/machine.c b/hw/core/machine.c
index 3d851d34da..7adbac6f87 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -56,6 +56,8 @@ GlobalProperty hw_compat_rhel_9_1[] = {
   { "nvme-ns", "eui64-default", "on"},
   /* hw_compat_rhel_9_1 from hw_compat_7_1 */
   { "virtio-device", "queue_reset", "false" },
+  /* hw_compat_rhel_9_1 bz 2155749 */
+  { "virtio-rng-pci", "vectors", "0" },
 };
 const size_t hw_compat_rhel_9_1_len = G_N_ELEMENTS(hw_compat_rhel_9_1);
 
-- 
2.31.1