kernel/sys.c: call disable_nonboot_cpus() in kernel_restart()

As kernel_power_off() calls disable_nonboot_cpus(), we may also want to
have kernel_restart() call disable_nonboot_cpus().  Doing so can help
machines that require boot cpu be the last alive cpu during reboot to
survive with kernel restart.

This fixes one reboot issue seen on imx6q (Cortex-A9 Quad).  The machine
requires that the restart routine be run on the primary cpu rather than
secondary ones.  Otherwise, the secondary core running the restart routine
will fail to come to online after reboot.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/kernel/sys.c b/kernel/sys.c
index 3a2dc1efc270fbea4aa0056f3f6157a26ccfcb44..e2d12b352d927a0ff9a5163c7c1a8d09c2be1d5a 100644 (file)
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -368,6 +368,7 @@ EXPORT_SYMBOL(unregister_reboot_notifier);
 void kernel_restart(char *cmd)
 {
        kernel_restart_prepare(cmd);
+       disable_nonboot_cpus();
        if (!cmd)
                printk(KERN_EMERG "Restarting system.\n");
        else