From 798a5b6c195d1c64fd5e9dd252381feb17e5ff22 Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Thu, 27 Jan 2022 15:44:15 -0600 Subject: tracing: Fix smatch warning for null glob in event_hist_trigger_parse() The recent rename of event_hist_trigger_parse() caused smatch re-evaluation of trace_events_hist.c and as a result an old warning was found: kernel/trace/trace_events_hist.c:6174 event_hist_trigger_parse() error: we previously assumed 'glob' could be null (see line 6166) glob should never be null (and apparently smatch can also figure that out and skip the warning when using the cross-function DB (but which can't be used with a 0day build as it takes too much time to generate)). Nonetheless for clarity, remove the test but add a WARN_ON() in case the code ever changes. Link: https://lkml.kernel.org/r/96925e5c1f116654ada7ea0613d930b1266b5e1c.1643319703.git.zanussi@kernel.org Fixes: f404da6e1d46c ("tracing: Add 'last error' error facility for hist triggers") Reported-by: kernel test robot Reported-by: Dan Carpenter Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_hist.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index cd9610688ddc..e0860146dd39 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -6164,7 +6164,9 @@ static int event_hist_trigger_parse(struct event_command *cmd_ops, lockdep_assert_held(&event_mutex); - if (glob && strlen(glob)) { + WARN_ON(!glob); + + if (strlen(glob)) { hist_err_clear(); last_cmd_set(file, param); } -- cgit v1.2.3