Saved write support was added to track the write bit of a pte after
marking the pte protnone. This was done so that AUTONUMA can convert
a write pte to protnone and still track the old write bit. When converting
it back we set the pte write bit correctly thereby avoiding a write fault
again. Hence enable the test only when CONFIG_NUMA_BALANCING is enabled and
use protnone protflags.

Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
---
 mm/debug_vm_pgtable.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 4c73e63b4ceb..8704901f6bd8 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -119,10 +119,14 @@ static void __init pte_savedwrite_tests(unsigned long 
pfn, pgprot_t prot)
 {
        pte_t pte = pfn_pte(pfn, prot);
 
+       if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
+               return;
+
        pr_debug("Validating PTE saved write\n");
        WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte))));
        WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte))));
 }
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)
 {
@@ -234,6 +238,9 @@ static void __init pmd_savedwrite_tests(unsigned long pfn, 
pgprot_t prot)
 {
        pmd_t pmd = pfn_pmd(pfn, prot);
 
+       if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
+               return;
+
        pr_debug("Validating PMD saved write\n");
        WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd))));
        WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd))));
@@ -1019,8 +1026,8 @@ static int __init debug_vm_pgtable(void)
        pmd_huge_tests(pmdp, pmd_aligned, prot);
        pud_huge_tests(pudp, pud_aligned, prot);
 
-       pte_savedwrite_tests(pte_aligned, prot);
-       pmd_savedwrite_tests(pmd_aligned, prot);
+       pte_savedwrite_tests(pte_aligned, protnone);
+       pmd_savedwrite_tests(pmd_aligned, protnone);
 
        pte_unmap_unlock(ptep, ptl);
 
-- 
2.26.2

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