From: "Aneesh Kumar K.V" <redacted>

With THP we set pmd to none, before we do pte_clear. Hence we can't
walk page table to get the pte lock ptr and verify whether it is locked.
THP do take pte lock before calling pte_clear. So we don't change the locking
rules here. It is that we can't use page table walking to check whether
pte locks are help with THP.

NOTE: This needs to be re-written. Not to be merged upstream.
Signed-off-by: Aneesh Kumar K.V <redacted>
---
 arch/powerpc/mm/pgtable.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 214130a..d77f94f 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c

@@ -224,6 +224,7 @@ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 #ifdef CONFIG_DEBUG_VM
 void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
 {
+#if 0
 	pgd_t *pgd;
 	pud_t *pud;
 	pmd_t *pmd;

@@ -237,6 +238,7 @@ void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
 	pmd = pmd_offset(pud, addr);
 	BUG_ON(!pmd_present(*pmd));
 	assert_spin_locked(pte_lockptr(mm, pmd));
+#endif
 }
 #endif /* CONFIG_DEBUG_VM */
 

-- 
1.8.1.2