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charset="UTF-8" ring_buffer_poll_remote() holds cpus_read_lock() while walking buffer->cpumask. Ring buffers are never freed on CPU hotunplug, and trace_rb_cpu_prepare() already orders buffer->buffers with the cpumask update (with rb_cpu_sync()). Drop cpus_read_lock() as it is unnecessary. Signed-off-by: Vincent Donnefort --- kernel/trace/ring_buffer.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index bd8126f6353b..32d3c47dbdf0 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -6918,8 +6918,6 @@ int ring_buffer_poll_remote(struct trace_buffer *buffer, int cpu) return 0; } - guard(cpus_read_lock)(); - /* * Make sure all the ring buffers are up to date before we start reading * them. -- 2.56.0.567.gdb80ae8cd5-goog