6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Helge Deller <deller@xxxxxx> commit 82b143aeb169b8b55798d7d2063032e1a6ceeeb0 upstream. This reverts commit 0921244f6f4f0d05698b953fe632a99b38907226. It broke CPU hotplugging because it modifies the __cpu_possible_mask after bootup, so that it will be different than nr_cpu_ids, which then effictively breaks the workqueue setup code and triggers crashes when shutting down CPUs at runtime. Guenter was the first who noticed the wrong values in __cpu_possible_mask, since the cpumask Kunit tests were failig. Reverting this commit fixes both issues, but sadly brings back this uncritical runtime warning: register_cpu_capacity_sysctl: too early to get CPU4 device! Signed-off-by: Helge Deller <deller@xxxxxx> Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx> Link: https://lkml.org/lkml/2024/2/4/146 Link: https://lore.kernel.org/lkml/Zb0mbHlIud_bqftx@xxxxxxxxxxxxxxx/t/ Cc: stable@xxxxxxxxxxxxxxx # 6.0+ Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/parisc/kernel/processor.c | 8 -------- 1 file changed, 8 deletions(-) --- a/arch/parisc/kernel/processor.c +++ b/arch/parisc/kernel/processor.c @@ -172,7 +172,6 @@ static int __init processor_probe(struct p->cpu_num = cpu_info.cpu_num; p->cpu_loc = cpu_info.cpu_loc; - set_cpu_possible(cpuid, true); store_cpu_topology(cpuid); #ifdef CONFIG_SMP @@ -474,13 +473,6 @@ static struct parisc_driver cpu_driver _ */ void __init processor_init(void) { - unsigned int cpu; - reset_cpu_topology(); - - /* reset possible mask. We will mark those which are possible. */ - for_each_possible_cpu(cpu) - set_cpu_possible(cpu, false); - register_parisc_driver(&cpu_driver); }
