[PATCH] ppc64: Add missing barrier() in kexec code
Mikey and I were testing kexec and hit a lockup. It turns out gcc 4.0
optimises the kexec_prepare_cpus loop so we avoid reloading paca.hw_cpu_id.
A gcc barrier() fixes the problem.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/ppc64/kernel/machine_kexec.c b/arch/ppc64/kernel/machine_kexec.c
index 4775f12..bf7cc4f 100644
--- a/arch/ppc64/kernel/machine_kexec.c
+++ b/arch/ppc64/kernel/machine_kexec.c
@@ -205,6 +205,7 @@
continue;
while (paca[i].hw_cpu_id != -1) {
+ barrier();
if (!cpu_possible(i)) {
printk("kexec: cpu %d hw_cpu_id %d is not"
" possible, ignoring\n",