[kernel-hardening][PATCH] arm: mm: idmap: Mark variables as ro_after_init

From: Jinbum Park
Date: Fri Dec 08 2017 - 06:13:41 EST


idmap_pgd, arch_phys_to_idmap_offset are setup once
while init stage, and never changed after that.
so, it is good candidate for __ro_after_init.

Signed-off-by: Jinbum Park <jinb.park7@xxxxxxxxx>
---
arch/arm/mm/idmap.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 10bfba8..1d1edd0 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -16,8 +16,8 @@
* are not supported on any CPU using the idmap tables as its current
* page tables.
*/
-pgd_t *idmap_pgd;
-long long arch_phys_to_idmap_offset;
+pgd_t *idmap_pgd __ro_after_init;
+long long arch_phys_to_idmap_offset __ro_after_init;

#ifdef CONFIG_ARM_LPAE
static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
--
1.9.1