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.kumar@xxxxxxxxxxxxx>
---
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 28f9d0558c20..5c0680836fe9 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)
{
@@ -235,6 +239,9 @@ 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))));
@@ -1020,8 +1027,8 @@ 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
