parisc/ftrace: Fix function graph tracing disablement

commit a5f05a138a8cac035bf9da9b6ed0e532bc7942c8 upstream.

Due to an apparent copy-paste bug, the parisc implementation of
ftrace_disable_ftrace_graph_caller() doesn't actually do anything.
It enables the (already-enabled) static key rather than disabling it.

The result is that after function graph tracing has been "disabled", any
subsequent (non-graph) function tracing will inadvertently also enable
the slow fgraph return address hijacking.

Fixes: 98f2926171ae ("parisc/ftrace: use static key to enable/disable function graph tracer")
Cc: stable@vger.kernel.org # 5.16+
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/parisc/kernel/ftrace.c b/arch/parisc/kernel/ftrace.c
index c91f9c2e61ed25e605dacd34a6f270282c022e34..f8d08eab7db8b051ddd41afc2535c88907eb8a0d 100644 (file)
--- a/arch/parisc/kernel/ftrace.c
+++ b/arch/parisc/kernel/ftrace.c
@@ -87,7 +87,7 @@ int ftrace_enable_ftrace_graph_caller(void)
 
 int ftrace_disable_ftrace_graph_caller(void)
 {
-       static_key_enable(&ftrace_graph_enable.key);
+       static_key_disable(&ftrace_graph_enable.key);
        return 0;
 }
 #endif