From 8db549491c4a3ce9e1d509b75f78516e497f48ec Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 11 Sep 2016 10:36:26 +0200 Subject: [PATCH] smp: Allocate smp_call_on_cpu() workqueue on stack too The SMP IPI struct descriptor is allocated on the stack except for the workqueue and lockdep complains: INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 0 PID: 110 Comm: kworker/0:1 Not tainted 4.8.0-rc5+ #14 Hardware name: Dell Inc. Precision T3600/0PTTT9, BIOS A13 05/11/2014 Workqueue: events smp_call_on_cpu_callback ... Call Trace: dump_stack register_lock_class ? __lock_acquire __lock_acquire ? __lock_acquire lock_acquire ? process_one_work process_one_work ? process_one_work worker_thread ? process_one_work ? process_one_work kthread ? kthread_create_on_node ret_from_fork So allocate it on the stack too. Signed-off-by: Peter Zijlstra (Intel) [ Test and write commit message. ] Signed-off-by: Borislav Petkov Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20160911084323.jhtnpb4b37t5tlno@pd.tnic Signed-off-by: Ingo Molnar --- kernel/smp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/smp.c b/kernel/smp.c index f4f6137941cb..bba3b201668d 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -759,13 +759,14 @@ static void smp_call_on_cpu_callback(struct work_struct *work) int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys) { struct smp_call_on_cpu_struct sscs = { - .work = __WORK_INITIALIZER(sscs.work, smp_call_on_cpu_callback), .done = COMPLETION_INITIALIZER_ONSTACK(sscs.done), .func = func, .data = par, .cpu = phys ? cpu : -1, }; + INIT_WORK_ONSTACK(&sscs.work, smp_call_on_cpu_callback); + if (cpu >= nr_cpu_ids || !cpu_online(cpu)) return -ENXIO; -- 2.20.1