[PATCH 1/3] virtio_iommu: Clear IOMMUPciBus pointer cache when system reset

[Zhenzhong Duan <zhenzhong.duan@intel.com>]

IOMMUPciBus pointer cache is indexed by bus number, bus number
may not always be a fixed value, i.e., guest reboot to different
kernel which set bus number with different algorithm.

This could lead to endpoint binding to wrong iommu MR in
virtio_iommu_get_endpoint(), then vfio device setup wrong
mapping from other device.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/virtio/virtio-iommu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 8a4bd933c6..bfce3237f3 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -1264,6 +1264,8 @@ static void virtio_iommu_system_reset(void *opaque)
 
     trace_virtio_iommu_system_reset();
 
+    memset(s->iommu_pcibus_by_bus_num, 0, sizeof(s->iommu_pcibus_by_bus_num));
+
     /*
      * config.bypass is sticky across device reset, but should be restored on
      * system reset
-- 
2.34.1