diff options
| author | Li Huafei <lihuafei1@huawei.com> | 2024-10-24 18:59:17 +0300 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2024-10-25 05:26:06 +0300 |
| commit | bd3734db86e01e20dd239a40b419059a0ce9c901 (patch) | |
| tree | b24f7bb0925bc56f8c0b40b005ee3f8d5aa276f0 | |
| parent | fae4078c289a2f24229c0de652249948b1cd6bdb (diff) | |
| download | linux-bd3734db86e01e20dd239a40b419059a0ce9c901.tar.xz | |
fgraph: Fix missing unlock in register_ftrace_graph()
Use guard(mutex)() to acquire and automatically release ftrace_lock,
fixing the issue of not unlocking when calling cpuhp_setup_state()
fails.
Fixes smatch warning:
kernel/trace/fgraph.c:1317 register_ftrace_graph() warn: inconsistent returns '&ftrace_lock'.
Link: https://lore.kernel.org/20241024155917.1019580-1-lihuafei1@huawei.com
Fixes: 2c02f7375e65 ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202410220121.wxg0olfd-lkp@intel.com/
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/fgraph.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 41e7a15dcb50..cd1c2946018c 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -1252,7 +1252,7 @@ int register_ftrace_graph(struct fgraph_ops *gops) int ret = 0; int i = -1; - mutex_lock(&ftrace_lock); + guard(mutex)(&ftrace_lock); if (!fgraph_initialized) { ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "fgraph_idle_init", @@ -1273,10 +1273,8 @@ int register_ftrace_graph(struct fgraph_ops *gops) } i = fgraph_lru_alloc_index(); - if (i < 0 || WARN_ON_ONCE(fgraph_array[i] != &fgraph_stub)) { - ret = -ENOSPC; - goto out; - } + if (i < 0 || WARN_ON_ONCE(fgraph_array[i] != &fgraph_stub)) + return -ENOSPC; gops->idx = i; ftrace_graph_active++; @@ -1313,8 +1311,6 @@ error: gops->saved_func = NULL; fgraph_lru_release_index(i); } -out: - mutex_unlock(&ftrace_lock); return ret; } |