diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2020-08-18 15:57:37 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-09-01 09:58:03 +0200 |
| commit | 0340a6b7fb767f7f296b9bacc9a215920519a644 (patch) | |
| tree | aa04f191d261cc7274fd07c14f46cb06bbf5d969 /kernel/trace | |
| parent | 70d932985757fbe978024db313001218e9f8fe5c (diff) | |
module: Fix up module_notifier return values
While auditing all module notifiers I noticed a whole bunch of fail
wrt the return value. Notifiers have a 'special' return semantics.
As is; NOTIFY_DONE vs NOTIFY_OK is a bit vague; but
notifier_from_errno(0) results in NOTIFY_OK and NOTIFY_DONE has a
comment that says "Don't care".
From this I've used NOTIFY_DONE when the function completely ignores
the callback and notifier_to_error() isn't used.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: Robert Richter <rric@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20200818135804.385360407@infradead.org
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 8 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_printk.c | 4 |
4 files changed, 10 insertions, 6 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a8d4f253ed77..2ecf7892a31b 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2027,10 +2027,11 @@ static int bpf_event_notify(struct notifier_block *nb, unsigned long op, { struct bpf_trace_module *btm, *tmp; struct module *mod = module; + int ret = 0; if (mod->num_bpf_raw_events == 0 || (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING)) - return 0; + goto out; mutex_lock(&bpf_module_mutex); @@ -2040,6 +2041,8 @@ static int bpf_event_notify(struct notifier_block *nb, unsigned long op, if (btm) { btm->module = module; list_add(&btm->list, &bpf_trace_modules); + } else { + ret = -ENOMEM; } break; case MODULE_STATE_GOING: @@ -2055,7 +2058,8 @@ static int bpf_event_notify(struct notifier_block *nb, unsigned long op, mutex_unlock(&bpf_module_mutex); - return 0; +out: + return notifier_from_errno(ret); } static struct notifier_block bpf_module_nb = { diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f40d850ebabc..df499922b6a4 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9072,7 +9072,7 @@ static int trace_module_notify(struct notifier_block *self, break; } - return 0; + return NOTIFY_OK; } static struct notifier_block trace_module_nb = { diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index a85effb2373b..beebf2cd364b 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2646,7 +2646,7 @@ static int trace_module_notify(struct notifier_block *self, mutex_unlock(&trace_types_lock); mutex_unlock(&event_mutex); - return 0; + return NOTIFY_OK; } static struct notifier_block trace_module_nb = { diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index d4e31e969206..bb7783b90361 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -96,7 +96,7 @@ static int module_trace_bprintk_format_notify(struct notifier_block *self, if (val == MODULE_STATE_COMING) hold_module_trace_bprintk_format(start, end); } - return 0; + return NOTIFY_OK; } /* @@ -174,7 +174,7 @@ __init static int module_trace_bprintk_format_notify(struct notifier_block *self, unsigned long val, void *data) { - return 0; + return NOTIFY_OK; } static inline const char ** find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos) |