mm: numa: add paranoid check around pte_protnone_numa

[cascardo/linux.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index bf244f5..f7886ab 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3013,6 +3013,9 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
        bool migrated = false;
        int flags = 0;
 
+       /* A PROT_NONE fault should not end up here */
+       BUG_ON(!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)));
+
        /*
        * The "pte" at this point cannot be used safely without
        * validation through pte_unmap_same(). It's of NUMA type but