kvm: Fix kvm_get_page_retry_io __gup retval check

Confusion around -EBUSY and zero (inside a BUG_ON no less).

Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3f16f569169eaf388ed4c7cf992f256d93665245..a1cf53ee0d286a5fa3a75229d3b0d407b27475c7 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1146,7 +1146,7 @@ int kvm_get_user_page_io(struct task_struct *tsk, struct mm_struct *mm,
        npages = __get_user_pages(tsk, mm, addr, 1, flags, pagep, NULL,
                                  &locked);
        if (!locked) {
-               VM_BUG_ON(npages != -EBUSY);
+               VM_BUG_ON(npages);
 
                if (!pagep)
                        return 0;