control page: warn on page fault

Page faults should not happen here.  Scream if they do anyway. This is
useful when extending the control page.

1 files changed, 7 insertions, 7 deletions

diff --git a/litmus/ctrldev.c b/litmus/ctrldev.c
index 294d134a4a6d..ec0fc4b1ab55 100644
--- a/litmus/ctrldev.c
+++ b/litmus/ctrldev.c
@@ -55,19 +55,19 @@ static void litmus_ctrl_vm_close(struct vm_area_struct* vma)
         TRACE_CUR(CTRL_NAME
                   ": %p:%p vma:%p vma->vm_private_data:%p closed.\n",
                   (void*) vma->vm_start, (void*) vma->vm_end, vma,
-                  vma->vm_private_data, current->comm,
-                  current->pid);
+                  vma->vm_private_data);
 }
 
 static int litmus_ctrl_vm_fault(struct vm_area_struct* vma,
                                       struct vm_fault* vmf)
 {
-        /* This function should never be called, since
-         * all pages should have been mapped by mmap()
-         * already. */
-        TRACE_CUR("%s flags=0x%x\n", __FUNCTION__, vma->vm_flags);
+        TRACE_CUR("%s flags=0x%x (off:%ld)\n", __FUNCTION__,
+                  vma->vm_flags, vmf->pgoff);
+
+        /* This function should never be called, since all pages should have
+         * been mapped by mmap() already. */
+        WARN_ONCE(1, "Page faults should be impossible in the control page\n");
 
-        /* nope, you only get one page */
         return VM_FAULT_SIGBUS;
 }