diff --git a/kernel/cpu.c b/kernel/cpu.c
index ad7d0b00bce9..7b36b3a4e336 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -3106,10 +3106,10 @@ const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL;
 EXPORT_SYMBOL(cpu_all_bits);
 
 #ifdef CONFIG_INIT_ALL_POSSIBLE
-struct cpumask __cpu_possible_mask __read_mostly
+struct cpumask __cpu_possible_mask __ro_after_init;
 	= {CPU_BITS_ALL};
 #else
-struct cpumask __cpu_possible_mask __read_mostly;
+struct cpumask __cpu_possible_mask __ro_after_init;
 #endif
 EXPORT_SYMBOL(__cpu_possible_mask);