[RFC PATCH v2 5/7] tracing/probe: Verify alloc_trace_*probe() result

[Masami Hiramatsu]

Since alloc_trace_*probe() returns -EINVAL only if !event && !group,
it should not happen in trace_*probe_create(). If we catch that case
there is a bug. So use WARN_ON_ONCE() instead of pr_info().

Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
---
 kernel/trace/trace_kprobe.c |    4 ++--
 kernel/trace/trace_uprobe.c |    3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 5222fd82e7e4..56324c231688 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -693,9 +693,9 @@ static int trace_kprobe_create(int argc, const char *argv[])
        tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,
                               argc, is_return);
        if (IS_ERR(tk)) {
-               pr_info("Failed to allocate trace_probe.(%d)\n",
-                       (int)PTR_ERR(tk));
                ret = PTR_ERR(tk);
+               /* This must return -ENOMEM otherwise there is a bug */
+               WARN_ON_ONCE(ret != -ENOMEM);
                goto out;
        }
 
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 52f033489377..b54137ec7810 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -514,8 +514,9 @@ static int trace_uprobe_create(int argc, const char **argv)
 
        tu = alloc_trace_uprobe(group, event, argc, is_return);
        if (IS_ERR(tu)) {
-               pr_info("Failed to allocate trace_uprobe.(%d)\n", 
(int)PTR_ERR(tu));
                ret = PTR_ERR(tu);
+               /* This must return -ENOMEM otherwise there is a bug */
+               WARN_ON_ONCE(ret != -ENOMEM);
                goto fail_address_parse;
        }
        tu->offset = offset;