From e5873d6f7a7aa5f9de73ca829034fcaaf7b1d25e Mon Sep 17 00:00:00 2001
From: Heiko Carstens <hca@linux.ibm.com>
Date: Fri, 1 Oct 2021 14:24:42 +0200
Subject: [PATCH] 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>
---
arch/s390/kernel/ftrace.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 04a3e88c58d7..e416aaaaf524 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;
}