From: Wang Qing <wangqing@xxxxxxxx> commit 1dc9f1a66e1718479e1c4f95514e1750602a3cb9 upstream. When ACPI is not enabled, cpuid_topo->llc_id = cpu_topo->llc_id = -1, which will set llc_sibling 0xff(...), this is misleading. Don't set llc_sibling(default 0) if we don't know the cache topology. Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx> Signed-off-by: Wang Qing <wangqing@xxxxxxxx> Fixes: 37c3ec2d810f ("arm64: topology: divorce MC scheduling domain from core_siblings") Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1649644580-54626-1-git-send-email-wangqing@xxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/base/arch_topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -515,7 +515,7 @@ void update_siblings_masks(unsigned int for_each_online_cpu(cpu) { cpu_topo = &cpu_topology[cpu]; - if (cpuid_topo->llc_id == cpu_topo->llc_id) { + if (cpu_topo->llc_id != -1 && cpuid_topo->llc_id == cpu_topo->llc_id) { cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling); cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling); }