KVM: MMU: fix huge page adapted on non-PAE host

The huge page size is 4M on non-PAE host, but 2M page size is used in
transparent_hugepage_adjust(), so the page we get after adjust the
mapping level is not the head page, the BUG_ON() will be triggered

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

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 72102e0..be3cea4 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2595,8 +2595,7 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
                        *gfnp = gfn;
                        kvm_release_pfn_clean(pfn);
                        pfn &= ~mask;
-                       if (!get_page_unless_zero(pfn_to_page(pfn)))
-                               BUG();
+                       kvm_get_pfn(pfn);
                        *pfnp = pfn;
                }
        }