On Mon, Jul 10, 2023 at 08:41:09AM +0200, Christoph Hellwig wrote: > 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 That is documented in Documentation/admin-guide/kdump/kdump.rst. On arm and ppc64, 'maxcpus=1' is passed for kdump kernel, and "maxcpu=1" simply keep one of CPU cores as online, and others as offline. So Cc our arch(arm & ppc64) & kdump guys wrt. passing 'maxcpus=1' for kdump kernel. > setups, otherwise you'll have to paper over it in all kind of > drivers. The issue is only triggered for drivers which use managed irq & multiple hw queues. Thanks, Ming
