livepatch/module: remove livepatch module notifier
Remove the livepatch module notifier in favor of directly enabling and
disabling patches to modules in the module loader. Hard-coding the
function calls ensures that ftrace_module_enable() is run before
klp_module_coming() during module load, and that klp_module_going() is
run before ftrace_release_mod() during module unload. This way, ftrace
and livepatch code is run in the correct order during the module
load/unload sequence without dependence on the module notifier call chain.
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/kernel/module.c b/kernel/module.c
index 6dbfad4..4b65fbb 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -53,6 +53,7 @@
#include <asm/sections.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
+#include <linux/livepatch.h>
#include <linux/async.h>
#include <linux/percpu.h>
#include <linux/kmemleak.h>
@@ -984,6 +985,7 @@
mod->exit();
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
+ klp_module_going(mod);
ftrace_release_mod(mod);
async_synchronize_full();
@@ -3315,6 +3317,7 @@
module_put(mod);
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
+ klp_module_going(mod);
ftrace_release_mod(mod);
free_module(mod);
wake_up_all(&module_wq);
@@ -3401,7 +3404,13 @@
static int prepare_coming_module(struct module *mod)
{
+ int err;
+
ftrace_module_enable(mod);
+ err = klp_module_coming(mod);
+ if (err)
+ return err;
+
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_COMING, mod);
return 0;
@@ -3553,6 +3562,7 @@
coming_cleanup:
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
+ klp_module_going(mod);
bug_cleanup:
/* module_bug_cleanup needs module_mutex protection */