[PATCH] riscv: Populate boot CPU topology on UP kernels

[Sudeep Holla]

On Tue, Oct 20, 2026 at 11:23:34AM +0100, Conor Dooley wrote:
> On Mon, Oct 12, 2026 at 09:10:33PM +0800, Chen Pei wrote:
> > RISC-V selects GENERIC_ARCH_TOPOLOGY unconditionally, so the topology
> > cpumask accessors resolve into cpu_topology[]. The RISC-V calls to
> > init_cpu_topology() and store_cpu_topology() are in smpboot.c, which is
> > only built with CONFIG_SMP. On UP kernels, cpu_topology[] remains
> > zero-initialized and its sibling masks are empty.
> 
> I'm curious about arm64 since they've got the same as us as far as I
> know. Is the same issue there or are they solving it in a different way?
> 

Commit 4b3dc9679cf7 ("arm64: force CONFIG_SMP=y and remove redundant #ifdefs")
removed UP support and made SMP default enabled.

-- 
Regards,
Sudeep