In the Linux kernel, the following vulnerability has been resolved: virtio-pci: Check if isavq is NULL [bug] In the virtiopcicommon.c function vpdelvqs, vpdev->isavq is involved to determine whether it is admin virtqueue, but this function vpdev->isavq may be empty. For installations, virtiopcilegacy does not assign a value to vpdev->isavq. [fix] Check whether it is vpdev->is_avq before use. [test] Test with virsh Attach device Before this patch, the following command would crash the guest system After applying the patch, everything seems to be working fine.