On 1/23/21 1:10 PM, Sebastian Andrzej Siewior wrote: > Patch 2+3 were applied and then dropped by Jens due to a NOHZ+softirq > related warning [0]. Turns out a successful wakeup via > set_nr_if_polling() will not process any softirqs and the CPU may go > back to idle. This is addressed by patch #1. > > smpcfd_dying_cpu() will also invoke SMP-functions calls via > flush_smp_call_function_queue() but the block layer shouldn't queue > anything because the CPU isn't online anymore. > The two caller of flush_smp_call_function_from_idle() look fine with > opening interrupts from within do_softirq(). > > [0] https://lkml.kernel.org/r/1ee4b31b-350e-a9f5-4349-cfb34b89829a@xxxxxxxxx I can queue up the block side once the IPI fix is in some stable branch that I can pull in. -- Jens Axboe
