On 29/07/19 10:58, Jack Wang wrote:
Vitaly Kuznetsov vkuznets@redhat.com 于2019年7月25日周四 下午3:29写道:
From: Paolo Bonzini pbonzini@redhat.com
[ Upstream commit 88dddc11a8d6b09201b4db9d255b3394d9bc9e57 ]
If a KVM guest is reset while running a nested guest, free_nested will disable the shadow VMCS execution control in the vmcs01. However, on the next KVM_RUN vmx_vcpu_run would nevertheless try to sync the VMCS12 to the shadow VMCS which has since been freed.
This causes a vmptrld of a NULL pointer on my machime, but Jan reports the host to hang altogether. Let's see how much this trivial patch fixes.
Reported-by: Jan Kiszka jan.kiszka@siemens.com Cc: Liran Alon liran.alon@oracle.com Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com
Hi all,
Do we need to backport the fix also to stable 4.14? It applies cleanly and compiles fine.
The reproducer required newer kernels that support KVM_GET_NESTED_STATE and KVM_SET_NESTED_STATE, so it would be hard to test it. However, the patch itself should be safe.
Paolo