From c791cc4b1feb881b3644c059dba5464b076bf592 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Tue, 16 Jun 2020 14:53:55 -0400 Subject: tracing: Only allow trace_array_printk() to be used by instances To prevent default "trace_printks()" from spamming the top level tracing ring buffer, only allow trace instances to use trace_array_printk() (which can be used without the trace_printk() start up warning). Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index bb62269724d5..8241d1448d70 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3346,12 +3346,16 @@ int trace_array_printk(struct trace_array *tr, int ret; va_list ap; - if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) - return 0; - if (!tr) return -ENOENT; + /* This is only allowed for created instances */ + if (tr == &global_trace) + return 0; + + if (!(tr->trace_flags & TRACE_ITER_PRINTK)) + return 0; + va_start(ap, fmt); ret = trace_array_vprintk(tr, ip, fmt, ap); va_end(ap); -- cgit v1.2.3