[PATCH 2/2] nvme-pci: use blk_mq_max_nr_hw_queues() to calculate io queues

[Christoph Hellwig]

On Sat, Jul 08, 2023 at 10:02:59AM +0800, Ming Lei wrote:
> Take blk-mq's knowledge into account for calculating io queues.
> 
> Fix wrong queue mapping in case of kdump kernel.
> 
> On arm and ppc64, 'maxcpus=1' is passed to kdump command line, see
> `Documentation/admin-guide/kdump/kdump.rst`, so num_possible_cpus()
> still returns all CPUs.

That's simply broken.  Please fix the arch code to make sure
it does not return a bogus num_possible_cpus value for these
setups, otherwise you'll have to paper over it in all kind of
drivers.