From b3ca80935100af47f226be439cb266378dab7bf7 Mon Sep 17 00:00:00 2001
From: Anton Blanchard <anton@samba.org>
Date: Tue, 27 Sep 2005 21:45:38 -0700
Subject: [PATCH] [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>
---
arch/ppc64/kernel/machine_kexec.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/ppc64/kernel/machine_kexec.c b/arch/ppc64/kernel/machine_kexec.c
index 4775f12a013c5..bf7cc4f8210f1 100644
--- a/arch/ppc64/kernel/machine_kexec.c
+++ b/arch/ppc64/kernel/machine_kexec.c
@@ -205,6 +205,7 @@ static void kexec_prepare_cpus(void)
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",
--
2.30.2