[PATCH] check return value of cpu_callback
Spawing ksoftirqd, migration, or watchdog, and calling init_timers_cpu()
may fail with small memory. If it happens in initcalls, kernel NULL
pointer dereference happens later. This patch makes crash happen
immediately in such cases. It seems a bit better than getting kernel NULL
pointer dereference later.
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/sched.c b/kernel/sched.c
index 5c848fd..b946209 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5272,9 +5272,11 @@
int __init migration_init(void)
{
void *cpu = (void *)(long)smp_processor_id();
+ int err;
/* Start one for the boot CPU: */
- migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
+ err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
+ BUG_ON(err == NOTIFY_BAD);
migration_call(&migration_notifier, CPU_ONLINE, cpu);
register_cpu_notifier(&migration_notifier);
