1 files changed, 11 insertions, 2 deletions

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 8b1231633dc5..bd3f88198308 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -74,12 +74,21 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
         long disabled;
         int cpu;
 
-        if (likely(!__get_cpu_var(tracing_cpu)))
+        /*
+         * Does not matter if we preempt. We test the flags
+         * afterward, to see if irqs are disabled or not.
+         * If we preempt and get a false positive, the flags
+         * test will fail.
+         */
+        cpu = raw_smp_processor_id();
+        if (likely(!per_cpu(tracing_cpu, cpu)))
                 return;
 
         local_save_flags(flags);
+        /* slight chance to get a false positive on tracing_cpu */
+        if (!irqs_disabled_flags(flags))
+                return;
 
-        cpu = raw_smp_processor_id();
         data = tr->data[cpu];
         disabled = atomic_inc_return(&data->disabled);