Re: [tj-wq:affinity-scopes-dbg-invalid-cpu] [workqueue] e3485721f9: WARNING:at_kernel/workqueue.c:#workqueue_online_cpu

From: Tejun Heo
Date: Mon Jun 12 2023 - 13:43:35 EST


On Mon, Jun 12, 2023 at 07:42:11AM -1000, Tejun Heo wrote:
> On Mon, Jun 12, 2023 at 10:04:02AM +0800, kernel test robot wrote:
> > [ 3.388228][ T21] ------------[ cut here ]------------
> > [ 3.394990][ T21] WARNING: CPU: 1 PID: 21 at kernel/workqueue.c:5393 workqueue_online_cpu (kernel/workqueue.c:5393 kernel/workqueue.c:5481)
> ...
> > [ 3.584746][ T21] ? workqueue_prepare_cpu (kernel/workqueue.c:5470)
> > [ 3.591752][ T21] ? local_clock (kernel/sched/clock.c:270 kernel/sched/clock.c:307)
> > [ 3.596749][ T21] cpuhp_invoke_callback (arch/x86/include/asm/jump_label.h:27 include/linux/jump_label.h:207 include/trace/events/cpuhp.h:65 kernel/cpu.c:193)
> > [ 3.603751][ T21] ? try_to_wake_up (include/linux/sched.h:2254 kernel/sched/core.c:4312)
> > [ 3.610751][ T21] cpuhp_thread_fun (kernel/cpu.c:815)
>
> This is set_cpus_allowed_ptr() failing on kworkers when workqueue tries to
> put back the per-cpu kworkers on the onlining CPU, which is rather
> unexpected. Let me include the error code in the warning message so that we
> can understand why it fails the next time.

Ah, never mind. This ->__pod_cpumaks not being initialized correctly by the
patch and is already fixed in the newer version of the code.

Thanks.

--
tejun