From: Amol Grover <frextrite@xxxxxxxxx> [ Upstream commit fd0e6852c407dd9aefc594f54ddcc21d84803d3b ] Fix following instances of sparse error kernel/trace/ftrace.c:5667:29: error: incompatible types in comparison kernel/trace/ftrace.c:5813:21: error: incompatible types in comparison kernel/trace/ftrace.c:5868:36: error: incompatible types in comparison kernel/trace/ftrace.c:5870:25: error: incompatible types in comparison Use rcu_dereference_protected to dereference the newly annotated pointer. Link: http://lkml.kernel.org/r/20200205055701.30195-1-frextrite@xxxxxxxxx Signed-off-by: Amol Grover <frextrite@xxxxxxxxx> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/trace/ftrace.c | 2 +- kernel/trace/trace.h | 8 ++++++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 6af28692f0f53..dd9fdb52e24ad 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5147,7 +5147,7 @@ static const struct file_operations ftrace_notrace_fops = { static DEFINE_MUTEX(graph_lock); struct ftrace_hash __rcu *ftrace_graph_hash = EMPTY_HASH; -struct ftrace_hash *ftrace_graph_notrace_hash = EMPTY_HASH; +struct ftrace_hash __rcu *ftrace_graph_notrace_hash = EMPTY_HASH; enum graph_filter_type { GRAPH_FILTER_NOTRACE = 0, diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 17f36488d3c84..757bb1bffed99 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -869,7 +869,7 @@ extern void __trace_graph_return(struct trace_array *tr, #ifdef CONFIG_DYNAMIC_FTRACE extern struct ftrace_hash __rcu *ftrace_graph_hash; -extern struct ftrace_hash *ftrace_graph_notrace_hash; +extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash; static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) { @@ -922,10 +922,14 @@ static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace) static inline int ftrace_graph_notrace_addr(unsigned long addr) { int ret = 0; + struct ftrace_hash *notrace_hash; preempt_disable_notrace(); - if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr)) + notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, + !preemptible()); + + if (ftrace_lookup_ip(notrace_hash, addr)) ret = 1; preempt_enable_notrace(); -- 2.20.1
