lib/smp_processor_id: Make migration check unconditional of SMP

Commit cac5cefbade90 ("sched/smp: Make SMP unconditional")
migrate_disable() even on UP builds.
Commit 06ddd17521bf1 ("sched/smp: Always define is_percpu_thread() and
scheduler_ipi()") made is_percpu_thread() check the affinity mask
instead replying always true for UP mask.

As a consequence smp_processor_id() now complains if invoked within a
migrate_disable() section because is_percpu_thread() checks its mask and
the migration check is left out.

Make migration check unconditional of SMP.

Fixes: cac5cefbade90 ("sched/smp: Make SMP unconditional")
Closes: https://lore.kernel.org/oe-lkp/202507100448.6b88d6f1-lkp@intel.com
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chen Yu <yu.c.chen@intel.com>
Link: https://lore.kernel.org/r/20250710082748.-DPO1rjO@linutronix.de

diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c
index a2bb7738c373cd964e5c5a793b2be29a08c384df..94b3f6b19538832f885560722d6f0fe55b87f207 100644 (file)
--- a/lib/smp_processor_id.c
+++ b/lib/smp_processor_id.c
@@ -22,10 +22,8 @@ unsigned int check_preemption_disabled(const char *what1, const char *what2)
        if (is_percpu_thread())
                goto out;
 
-#ifdef CONFIG_SMP
        if (current->migration_disabled)
                goto out;
-#endif
 
        /*
         * It is valid to assume CPU-locality during early bootup: