[mm,v4,33/39] kasan: mark kasan_arg_stacktrace as __initdata

Commit Message

[e-mail] Dec. 20, 2021, 10:02 p.m. UTC

From: Andrey Konovalov <[e-mail]>

As kasan_arg_stacktrace is only used in __init functions, mark it as
__initdata instead of __ro_after_init to allow it be freed after boot.

The other enums for KASAN args are used in kasan_init_hw_tags_cpu(),
which is not marked as __init as a CPU can be hot-plugged after boot.
Clarify this in a comment.

Signed-off-by: Andrey Konovalov <[e-mail]>
Suggested-by: Marco Elver <[e-mail]>

---

Changes v1->v2:
- Add this patch.
---
 mm/kasan/hw_tags.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

Patch

diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index 2e9378a4f07f..6509809dd5d8 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -40,7 +40,7 @@  enum kasan_arg_stacktrace {
 
 static enum kasan_arg kasan_arg __ro_after_init;
 static enum kasan_arg_mode kasan_arg_mode __ro_after_init;
-static enum kasan_arg_stacktrace kasan_arg_stacktrace __ro_after_init;
+static enum kasan_arg_stacktrace kasan_arg_stacktrace __initdata;
 
 /* Whether KASAN is enabled at all. */
 DEFINE_STATIC_KEY_FALSE(kasan_flag_enabled);
@@ -116,7 +116,10 @@  static inline const char *kasan_mode_info(void)
 		return "sync";
 }
 
-/* kasan_init_hw_tags_cpu() is called for each CPU. */
+/*
+ * kasan_init_hw_tags_cpu() is called for each CPU.
+ * Not marked as __init as a CPU can be hot-plugged after boot.
+ */
 void kasan_init_hw_tags_cpu(void)
 {
 	/*