summaryrefslogtreecommitdiffstats
path: root/arch/i386/kernel/smpboot.c
diff options
context:
space:
mode:
authorJeff Garzik <jeff@garzik.org>2006-03-24 09:24:04 -0500
committerJeff Garzik <jeff@garzik.org>2006-03-24 09:24:04 -0500
commit11ed56fb7899f9eb9eaef8e5919db1bf08f1b07e (patch)
treeb01421cb139b11065d776ed361a7a12b3a1aecc9 /arch/i386/kernel/smpboot.c
parent54da9a3968448681d0ddf193ec90f2480c5cba1c (diff)
parent2cc432eed0491df66e14b578139bba2c75fb3f9a (diff)
Merge branch 'upstream'
Conflicts: drivers/scsi/sata_vsc.c
Diffstat (limited to 'arch/i386/kernel/smpboot.c')
-rw-r--r--arch/i386/kernel/smpboot.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index eba7f53f8b4..7007e178379 100644
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -1029,6 +1029,16 @@ int __devinit smp_prepare_cpu(int cpu)
int apicid, ret;
lock_cpu_hotplug();
+
+ /*
+ * On x86, CPU0 is never offlined. Trying to bring up an
+ * already-booted CPU will hang. So check for that case.
+ */
+ if (cpu_online(cpu)) {
+ ret = -EINVAL;
+ goto exit;
+ }
+
apicid = x86_cpu_to_apicid[cpu];
if (apicid == BAD_APICID) {
ret = -ENODEV;