arm64: smp: Do not mark secondary CPUs possible under nosmp

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Under nosmp (maxcpus=0), arm64 never brings up secondary CPUs.

smp_prepare_cpus() already treats this as a UP-mandated boot and returns
before marking secondary CPUs present. However, smp_init_cpus() may still
enumerate firmware-described secondary CPUs and mark them possible before
that point.

Avoid marking secondary CPUs possible when nosmp/maxcpus=0 is in effect,
so that cpu_possible_mask reflects the nosmp boot policy for this boot.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Pengjie Zhang <zhangpengjie2@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>

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Pengjie Zhang 2026-05-06 17:08:51 +08:00 • committed by Will Deacon

parent 827ce94e08

commit e7cec385d2

1 changed files with 10 additions and 4 deletions

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arch/arm64/kernel/smp.c

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