[PATCH 3/3] module: Properly propagate MODULE_STATE_COMING failure

[Peter Zijlstra]

Now that notifiers got unbroken; use the proper interface to handle
notifier errors and propagate them.

There were already MODULE_STATE_COMING notifiers that failed; notably:

 - jump_label_module_notifier()
 - tracepoint_module_notify()
 - bpf_event_notify()

By propagating this error, we fix those users.

Cc: Jessica Yu <jeyu@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Martin KaFai Lau <kafai@xxxxxx>
Cc: Song Liu <songliubraving@xxxxxx>
Cc: Yonghong Song <yhs@xxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: netdev@xxxxxxxxxxxxxxx
Cc: bpf@xxxxxxxxxxxxxxx
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 kernel/module.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/kernel/module.c
+++ b/kernel/module.c
@@ -3643,9 +3643,10 @@ static int prepare_coming_module(struct
 	if (err)
 		return err;
 
-	blocking_notifier_call_chain(&module_notify_list,
-				     MODULE_STATE_COMING, mod);
-	return 0;
+	err = blocking_notifier_call_chain_error(&module_notify_list,
+			MODULE_STATE_COMING, MODULE_STATE_GOING, mod);
+
+	return notifier_to_errno(err);
 }
 
 static int unknown_module_param_cb(char *param, char *val, const char *modname,