From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Tue, 5 Apr 2011 04:34:58 +0000 (+1000)
Subject: powerpc: Perform an isync to synchronize CPUs coming out of secondary_hold
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=dd797738643cd3c2dd9cdff7e4c3a04d318ab23a;p=deliverable%2Flinux.git

powerpc: Perform an isync to synchronize CPUs coming out of secondary_hold

We need to do that to guarantee they see any code change done by
dynamic patching during boot.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 0700e1135c91..6d17c37f22a1 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -147,6 +147,8 @@ __secondary_hold:
 	mtctr	r4
 	mr	r3,r24
 	li	r4,0
+	/* Make sure that patched code is visible */
+	isync
 	bctr
 #else
 	BUG_OPCODE