kvm: free resources after canceling async_pf

When we cancel 'async_pf_execute()', we should behave as if the work was
never scheduled in 'kvm_setup_async_pf()'.
Fixes a bug when we can't unload module because the vm wasn't destroyed.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index ea475cd03511..8a39dda7a325 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -101,8 +101,11 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu)
                                    typeof(*work), queue);
                 cancel_work_sync(&work->work);
                 list_del(&work->queue);
-                if (!work->done) /* work was canceled */
+                if (!work->done) { /* work was canceled */
+                        mmdrop(work->mm);
+                        kvm_put_kvm(vcpu->kvm); /* == work->vcpu->kvm */
                         kmem_cache_free(async_pf_cache, work);
+                }
         }
 
         spin_lock(&vcpu->async_pf.lock);