On Thu, 24 Jul 2025 at 23:16, Russell King (Oracle)
[off-list ref] wrote:

On Thu, Jul 24, 2025 at 10:56:03PM +0530, Suchit Karunakaran wrote:

quoted

Previously, the NR_CPUS config for ARM required a minimum of 2 CPUs.
This patch changes the minimum NR_CPUS to 1 when SMP is not enabled,
sets range to exactly 1 if !SMP, allowing only a single CPU setting and
adds conditional defaults:
    - default to 1 if SMP is disabled (uniprocessor)
    - default to 4 if SMP is enabled (multiprocessor)

Signed-off-by: Suchit Karunakaran <redacted>

This hasn't been tested. NR_CPUS depends on SMP, so if SMP is not
enabled, then NR_CPUS doesn't exist in the configuration. Therefore,
providing a default for !SMP is meaningless.

Oops, I think I misunderstood the intent of commit
278d1ed65e25d80af7c3a112d707b3f70516ddb4(cpumask: make CONFIG_NR_CPUS
always valid). And sorry for not testing it, I wasn't exactly sure how
to test it. Could you please point out the issues so I can fix them
properly? I appreciate your patience. I’m still learning my way around
kernel development and trying to improve. Thanks!