[PATCH] proc: export page young and skip_kasan_poison flag via kpageflags

[Xin Hao <xhao@linux.alibaba.com>]

Now the young and skip_kasan_poison flag are supported in
show_page_flags(), but we can not get them from /proc/kpageflags,
So there add them.

Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
---
 fs/proc/page.c                    | 6 ++++++
 include/linux/kernel-page-flags.h | 2 ++
 tools/vm/page-types.c             | 4 ++++
 3 files changed, 12 insertions(+)

diff --git a/fs/proc/page.c b/fs/proc/page.c
index 9f1077d94cde..fd28e1d92c5c 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -220,6 +220,12 @@ u64 stable_page_flags(struct page *page)
 #ifdef CONFIG_64BIT
 	u |= kpf_copy_bit(k, KPF_ARCH_2,	PG_arch_2);
 #endif
+#if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT)
+	u |= kpf_copy_bit(k, KPF_YOUNG, PG_young);
+#endif
+#ifdef CONFIG_KASAN_HW_TAGS
+	u |= kpf_copy_bit(k, KPF_SKIP_KASAN_POSION, PG_skip_kasan_poison);
+#endif
 
 	return u;
 };
diff --git a/include/linux/kernel-page-flags.h b/include/linux/kernel-page-flags.h
index eee1877a354e..30aaa0ee4ca9 100644
--- a/include/linux/kernel-page-flags.h
+++ b/include/linux/kernel-page-flags.h
@@ -18,5 +18,7 @@
 #define KPF_UNCACHED		39
 #define KPF_SOFTDIRTY		40
 #define KPF_ARCH_2		41
+#define KPF_YOUNG		42
+#define KPF_SKIP_KASAN_POSION	43
 
 #endif /* LINUX_KERNEL_PAGE_FLAGS_H */
diff --git a/tools/vm/page-types.c b/tools/vm/page-types.c
index b1ed76d9a979..2671b746d11f 100644
--- a/tools/vm/page-types.c
+++ b/tools/vm/page-types.c
@@ -79,6 +79,8 @@
 #define KPF_UNCACHED		39
 #define KPF_SOFTDIRTY		40
 #define KPF_ARCH_2		41
+#define KPF_YOUNG		42
+#define KPF_SKIP_KASAN_POSION	43
 
 /* [48-] take some arbitrary free slots for expanding overloaded flags
  * not part of kernel API
@@ -137,6 +139,8 @@ static const char * const page_flag_names[] = {
 	[KPF_UNCACHED]		= "c:uncached",
 	[KPF_SOFTDIRTY]		= "f:softdirty",
 	[KPF_ARCH_2]		= "H:arch_2",
+	[KPF_YOUNG]		= "y:young",
+	[KPF_SKIP_KASAN_POSION]	= "K:skip_kasan_posion",
 
 	[KPF_READAHEAD]		= "I:readahead",
 	[KPF_SLOB_FREE]		= "P:slob_free",
-- 
2.31.0