KVM: remove dummy pages

Currently, kvm allocates some pages and use them as error indicators,
it wastes memory and is not good for scalability

Base on Avi's suggestion, we use the error codes instead of these pages
to indicate the error conditions

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index ebae24b62c90..79722782d9d7 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -203,8 +203,7 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu)
         if (!work)
                 return -ENOMEM;
 
-        work->page = bad_page;
-        get_page(bad_page);
+        work->page = get_bad_page();
         INIT_LIST_HEAD(&work->queue); /* for list_del to work */
 
         spin_lock(&vcpu->async_pf.lock);