On Thu, Aug 10, 2023 at 08:09:27AM +0800, Ming Lei wrote: > 1) some archs support 'nr_cpus=1' for kdump kernel, which is fine, since > num_possible_cpus becomes 1. > > 2) some archs do not support 'nr_cpus=1', and have to rely on > 'max_cpus=1', so num_possible_cpus isn't changed, and kernel just boots > with single online cpu. That causes trouble because blk-mq limits single > queue. And we need to fix case 2. We need to drop the is_kdump support, and if they want to force less cpus they need to make nr_cpus=1 work.
