From 0c97bf863efce63d6ab7971dad811601e6171d2f Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Thu, 23 May 2019 14:45:35 +0200 Subject: tracing: Silence GCC 9 array bounds warning Starting with GCC 9, -Warray-bounds detects cases when memset is called starting on a member of a struct but the size to be cleared ends up writing over further members. Such a call happens in the trace code to clear, at once, all members after and including `seq` on struct trace_iterator: In function 'memset', inlined from 'ftrace_dump' at kernel/trace/trace.c:8914:3: ./include/linux/string.h:344:9: warning: '__builtin_memset' offset [8505, 8560] from the object at 'iter' is out of the bounds of referenced subobject 'seq' with type 'struct trace_seq' at offset 4368 [-Warray-bounds] 344 | return __builtin_memset(p, c, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ In order to avoid GCC complaining about it, we compute the address ourselves by adding the offsetof distance instead of referring directly to the member. Since there are two places doing this clear (trace.c and trace_kdb.c), take the chance to move the workaround into a single place in the internal header. Link: http://lkml.kernel.org/r/20190523124535.GA12931@gmail.com Signed-off-by: Miguel Ojeda [ Removed unnecessary parenthesis around "iter" ] Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2c92b3d9ea30..1c80521fd436 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -8910,12 +8910,8 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) cnt++; - /* reset all but tr, trace, and overruns */ - memset(&iter.seq, 0, - sizeof(struct trace_iterator) - - offsetof(struct trace_iterator, seq)); + trace_iterator_reset(&iter); iter.iter_flags |= TRACE_FILE_LAT_FMT; - iter.pos = -1; if (trace_find_next_entry_inc(&iter) != NULL) { int ret; -- cgit v1.2.3 From ff585c5b9a27e64084c84e2ddf24fd00bf8dcfc1 Mon Sep 17 00:00:00 2001 From: YueHaibing Date: Fri, 14 Jun 2019 23:32:10 +0800 Subject: tracing: Make two symbols static Fix sparse warnings: kernel/trace/trace.c:6927:24: warning: symbol 'get_tracing_log_err' was not declared. Should it be static? kernel/trace/trace.c:8196:15: warning: symbol 'trace_instance_dir' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20190614153210.24424-1-yuehaibing@huawei.com Acked-by: Tom Zanussi Reported-by: Hulk Robot Signed-off-by: YueHaibing Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 1c80521fd436..83e08b78dbee 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -6923,7 +6923,7 @@ struct tracing_log_err { static DEFINE_MUTEX(tracing_err_log_lock); -struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) +static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) { struct tracing_log_err *err; @@ -8192,7 +8192,7 @@ static const struct file_operations buffer_percent_fops = { .llseek = default_llseek, }; -struct dentry *trace_instance_dir; +static struct dentry *trace_instance_dir; static void init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); -- cgit v1.2.3