From: Daniel Wagner Date: Mon, 16 Dec 2019 16:15:57 +0100 Subject: [PATCH 312/351] lib/smp_processor_id: Adjust check_preemption_disabled() Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=2e1705477262342382e7423129edb2e570567b53 [ Upstream commit af3c1c5fdf177870fb5e6e16b24e374696ab28f5 ] The current->migrate_disable counter is not always defined leading to build failures with DEBUG_PREEMPT && !PREEMPT_RT_BASE. Restrict the access to ->migrate_disable to same set where ->migrate_disable is modified. Signed-off-by: Daniel Wagner Signed-off-by: Steven Rostedt (VMware) [bigeasy: adjust condition + description] Signed-off-by: Sebastian Andrzej Siewior --- lib/smp_processor_id.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index 0c80992aa337..2e7398534b66 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -22,8 +22,10 @@ notrace static unsigned int check_preemption_disabled(const char *what1, * Kernel threads bound to a single CPU can safely use * smp_processor_id(): */ +#if defined(CONFIG_PREEMPT_RT_BASE) && (defined(CONFIG_SMP) || defined(CONFIG_SCHED_DEBUG)) if (current->migrate_disable) goto out; +#endif if (current->nr_cpus_allowed == 1) goto out;