Commit 82b143ae authored by Helge Deller's avatar Helge Deller
Browse files

Revert "parisc: Only list existing CPUs in cpu_possible_mask" 



This reverts commit 0921244f.

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: default avatarHelge Deller <deller@gmx.de>
Reported-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lkml.org/lkml/2024/2/4/146
Link: https://lore.kernel.org/lkml/Zb0mbHlIud_bqftx@slm.duckdns.org/t/
Cc: stable@vger.kernel.org # 6.0+
parent 54be6c6c

arch/parisc/kernel/processor.c

+0 −8
Original line number Diff line number Diff line
@@ -172,7 +172,6 @@ static int __init processor_probe(struct parisc_device *dev) 
	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 __refdata = { 
 */

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);

}