arch/x86/mm/pgtable.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 3481b35cb4ec..0a3d67ec73d4 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -706,12 +706,16 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
 
 	mtrr = mtrr_type_lookup(addr, addr + PUD_SIZE, &uniform);
 	if ((mtrr != MTRR_TYPE_INVALID) && (!uniform) &&
-	    (mtrr != MTRR_TYPE_WRBACK))
+	    (mtrr != MTRR_TYPE_WRBACK)) {
+		pr_debug("mtrr_type_lookup() returned %d (%d)\n", mtrr, uniform);
 		return 0;
+	}
 
 	/* Bail out if we are we on a populated non-leaf entry: */
-	if (pud_present(*pud) && !pud_huge(*pud))
+	if (pud_present(*pud) && !pud_huge(*pud)) {
+		pr_debug("pud is already present (%lx)\n", (unsigned long)pud_val(*pud));
 		return 0;
+	}
 
 	set_pte((pte_t *)pud, pfn_pte(
 		(u64)addr >> PAGE_SHIFT,