From: Heiko Carstens <hca@linux.ibm.com>
Date: Fri, 1 Oct 2021 12:24:42 +0000 (+0200)
Subject: s390/ftrace: add missing serialization for graph caller patching
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e5873d6f7a7aa5f9de73ca829034fcaaf7b1d25e;p=linux.git

s390/ftrace: add missing serialization for graph caller patching

CPUs must be serialized also when ftrace_graph_caller gets patched.
This is missing since ftrace function graph support was added on s390.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
---

diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 04a3e88c58d75..e416aaaaf524c 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -268,12 +268,14 @@ NOKPROBE_SYMBOL(prepare_ftrace_return);
 int ftrace_enable_ftrace_graph_caller(void)
 {
 	brcl_disable(ftrace_graph_caller);
+	text_poke_sync_lock();
 	return 0;
 }
 
 int ftrace_disable_ftrace_graph_caller(void)
 {
 	brcl_enable(ftrace_graph_caller);
+	text_poke_sync_lock();
 	return 0;
 }