From: Heiko Carstens <hca@linux.ibm.com>
Date: Wed, 17 Feb 2021 06:13:02 +0000 (+0100)
Subject: s390/smp: __smp_rescan_cpus() - move cpumask away from stack
X-Git-Tag: v4.14.226~56
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=30b560866423aee60d1314532dec9eb5813920db;p=thirdparty%2Fkernel%2Fstable.git

s390/smp: __smp_rescan_cpus() - move cpumask away from stack

[ Upstream commit 62c8dca9e194326802b43c60763f856d782b225c ]

Avoid a potentially large stack frame and overflow by making
"cpumask_t avail" a static variable. There is no concurrent
access due to the existing locking.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 40946c8587a54..d43b48d8f67d8 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -761,7 +761,7 @@ static int smp_add_core(struct sclp_core_entry *core, cpumask_t *avail,
 static int __smp_rescan_cpus(struct sclp_core_info *info, bool early)
 {
 	struct sclp_core_entry *core;
-	cpumask_t avail;
+	static cpumask_t avail;
 	bool configured;
 	u16 core_id;
 	int nr, i;