From 5da2c8f11e89601eea38cb9f3302f930c60806e7 Mon Sep 17 00:00:00 2001
Message-Id: <5da2c8f11e89601eea38cb9f3302f930c60806e7.1599166691.git.zanussi@kernel.org>
In-Reply-To: <56457dc415803c8abc5acb513ada877a79596f05.1599166690.git.zanussi@kernel.org>
References: <56457dc415803c8abc5acb513ada877a79596f05.1599166690.git.zanussi@kernel.org>
From: Daniel Wagner <dwagner@suse.de>
Date: Mon, 16 Dec 2019 16:15:57 +0100
Subject: [PATCH 313/333] lib/smp_processor_id: Adjust
 check_preemption_disabled()
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.142-rt63.tar.xz

[ 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 <dwagner@suse.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
[bigeasy: adjust condition + description]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 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;
-- 
2.17.1

