From: Jan Kiszka <jan.kis...@siemens.com>
cpu_buffer->current_context is supposed to be protected by irq
disabling, just like in dovetail.
Signed-off-by: Jan Kiszka <jan.kis...@siemens.com>
---
No-arch branches updated with this already.
kernel/trace/ring_buffer.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index dfaeee5b54e3..90be9e613887 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2726,9 +2726,9 @@ rb_wakeups(struct ring_buffer *buffer, struct
ring_buffer_per_cpu *cpu_buffer)
static __always_inline int
trace_recursive_lock(struct ring_buffer_per_cpu *cpu_buffer)
{
- unsigned int val = cpu_buffer->current_context;
unsigned long pc = preempt_count();
unsigned long flags;
+ unsigned int val;
int bit;
if (!(pc & (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET)))
@@ -2739,6 +2739,8 @@ trace_recursive_lock(struct ring_buffer_per_cpu
*cpu_buffer)
flags = hard_local_irq_save();
+ val = cpu_buffer->current_context;
+
if (unlikely(val & (1 << (bit + cpu_buffer->nest)))) {
/*
* It is possible that this was called by transitioning
--
2.26.2
