idle: Add the stack canary init to cpu_startup_entry()

[linux.git] / kernel / cpu / idle.c

diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c
index d5585f5e038ee1080f17777792a6927d5897e5ea..bf2ee1aafa0ef0e0859a9006cf51a51aa7150452 100644 (file)
--- a/kernel/cpu/idle.c
+++ b/kernel/cpu/idle.c
@@ -5,6 +5,7 @@
 #include <linux/cpu.h>
 #include <linux/tick.h>
 #include <linux/mm.h>
+#include <linux/stackprotector.h>
 
 #include <asm/tlb.h>
 
@@ -112,6 +113,21 @@ static void cpu_idle_loop(void)
 
 void cpu_startup_entry(enum cpuhp_state state)
 {
+       /*
+        * This #ifdef needs to die, but it's too late in the cycle to
+        * make this generic (arm and sh have never invoked the canary
+        * init for the non boot cpus!). Will be fixed in 3.11
+        */
+#ifdef CONFIG_X86
+       /*
+        * If we're the non-boot CPU, nothing set the stack canary up
+        * for us. The boot CPU already has it initialized but no harm
+        * in doing it again. This is a good place for updating it, as
+        * we wont ever return from this function (so the invalid
+        * canaries already on the stack wont ever trigger).
+        */
+       boot_init_stack_canary();
+#endif
        current_set_polling();
        arch_cpu_idle_prepare();
        cpu_idle_loop();