diff mbox series

[v3,5/5] arm64: pgtable: Warn unexpected pmdp_test_and_clear_young()

Message ID 20241022092734.59984-6-yangyicong@huawei.com (mailing list archive)
State New, archived
Headers show
Series Support Armv8.9/v9.4 FEAT_HAFT | expand

Commit Message

Yicong Yang Oct. 22, 2024, 9:27 a.m. UTC 
From: Yicong Yang <yangyicong@hisilicon.com>

Young bit operation on PMD table entry is only supported if
FEAT_HAFT enabled system widely. Add a warning for notifying
the misbehaviour.

Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
---
 arch/arm64/include/asm/pgtable.h | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index e4712b969aba..bb0600a24016 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1265,6 +1265,8 @@  static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 					    unsigned long address,
 					    pmd_t *pmdp)
 {
+	/* Operation applies to PMD table entry only if FEAT_HAFT is enabled */
+	VM_WARN_ON(pmd_table(READ_ONCE(*pmdp)) && !system_support_haft());
 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */