linux-kernel - [PATCH] arm64: move smp_send

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250620111045.3364827-1-arnd@kernel.org>
Date: Fri, 20 Jun 2025 13:10:41 +0200
From: Arnd Bergmann <arnd@...nel.org>
To: Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will@...nel.org>
Cc: Arnd Bergmann <arnd@...db.de>,
	Jonathan Cameron <Jonathan.Cameron@...wei.com>,
	Gavin Shan <gshan@...hat.com>,
	Jean-Philippe Brucker <jean-philippe@...aro.org>,
	James Morse <james.morse@....com>,
	Douglas Anderson <dianders@...omium.org>,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] arm64: move smp_send_stop() cpu mask off stack

From: Arnd Bergmann <arnd@...db.de>

For really large values of CONFIG_NR_CPUS, a CPU mask value should
not be put on the stack:

arch/arm64/kernel/smp.c:1188:1: error: the frame size of 8544 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]

This could be achieved using alloc_cpumask_var(), which makes it
depend on CONFIG_CPUMASK_OFFSTACK, but as this function is already
serialized and can only run on one CPU, making the variable 'static'
is easier.

Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
 arch/arm64/kernel/smp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 15987100c0cf..5c605dc7f5be 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -1107,7 +1107,7 @@ static inline unsigned int num_other_online_cpus(void)
 void smp_send_stop(void)
 {
 	static unsigned long stop_in_progress;
-	cpumask_t mask;
+	static cpumask_t mask;
 	unsigned long timeout;
 
 	/*
-- 
2.39.5