From: Ignacio Moreno Gonzalez <Ignacio.MorenoGonzalez@xxxxxxxx>
VM_NOHUGEPAGE is a no-op if CONFIG_TRANSPARENT_HUGEPAGE is disabled. So
it makes no sense to return an error when calling madvise() with
MADV_NOHUGEPAGE in that case.
Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Ignacio Moreno Gonzalez <Ignacio.MorenoGonzalez@xxxxxxxx>
Reviewed-by: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
---
include/linux/huge_mm.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 2f190c90192d..1a8082c61e01 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -506,6 +506,8 @@ bool unmap_huge_pmd_locked(struct vm_area_struct *vma, unsigned long addr,
#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+#include <uapi/asm/mman.h>
+
static inline bool folio_test_pmd_mappable(struct folio *folio)
{
return false;
@@ -595,6 +597,9 @@ static inline bool unmap_huge_pmd_locked(struct vm_area_struct *vma,
static inline int hugepage_madvise(struct vm_area_struct *vma,
unsigned long *vm_flags, int advice)
{
+ /* On a !THP kernel, MADV_NOHUGEPAGE is a no-op, but MADV_HUGEPAGE is not supported */
+ if (advice == MADV_NOHUGEPAGE)
+ return 0;
return -EINVAL;
}
--
2.49.0
