The cpuhp online/offline processing race also exists in percpu-mode hwlat tracer in theory, apply the fix too. That is: T1 | T2 [CPUHP_ONLINE] | cpu_device_down() hwlat_hotplug_workfn() | | cpus_write_lock() | takedown_cpu(1) | cpus_write_unlock() [CPUHP_OFFLINE] | cpus_read_lock() | start_kthread(1) | cpus_read_unlock() | Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/20240924094515.3561410-5-liwei391@huawei.com Fixes: ba998f7d95 ("trace/hwlat: Support hotplug operations") Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
ba998f7d95