[PATCH 1/2] mm: Change mmap_rnd_bits_max to __ro_after_init

Sami Tolvanen
2023-09-29T21:12:03Z

Allow mmap_rnd_bits_max to be updated on architectures that
determine virtual address space size at runtime instead of relying
on Kconfig options by changing it from const to __ro_after_init.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
include/linux/mm.h | 2 +-
mm/mmap.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index bf5d0b1b16f4..72a98b2afaf9 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -86,7 +86,7 @@ extern int sysctl_legacy_va_layout;

#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
extern const int mmap_rnd_bits_min;
-extern const int mmap_rnd_bits_max;
+extern int mmap_rnd_bits_max __ro_after_init;
extern int mmap_rnd_bits __read_mostly;
#endif
#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
diff --git a/mm/mmap.c b/mm/mmap.c
index b56a7f0c9f85..ed1b178b223a 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -64,7 +64,7 @@

#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
const int mmap_rnd_bits_min = CONFIG_ARCH_MMAP_RND_BITS_MIN;
-const int mmap_rnd_bits_max = CONFIG_ARCH_MMAP_RND_BITS_MAX;
+int mmap_rnd_bits_max __ro_after_init = CONFIG_ARCH_MMAP_RND_BITS_MAX;
int mmap_rnd_bits __read_mostly = CONFIG_ARCH_MMAP_RND_BITS;
#endif
#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
--
2.42.0.582.g8ccd20d70d-goog