From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Date: Tue, 21 Sep 2021 11:59:59 +0000 (+0100)
Subject: ARM: imx6: mark OCRAM mapping read-only
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4aede550f104158963260cdb736d0889a7671d6f;p=linux.git

ARM: imx6: mark OCRAM mapping read-only

iMX6 needs to write some code to OCRAM which resumes the DDR controller
after suspend. However, merely using __arm_ioremap_exec() causes the
kernel to complain of a W+X mapping. Solve this by using the newly
introduced __arm_iomem_set_ro() function to prevent inadvertent or
malicious writes to code we may later execute.

Tested-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---

diff --git a/arch/arm/mach-imx/pm-imx6.c b/arch/arm/mach-imx/pm-imx6.c
index 9244437cb1b9b..5c16257872a59 100644
--- a/arch/arm/mach-imx/pm-imx6.c
+++ b/arch/arm/mach-imx/pm-imx6.c
@@ -571,6 +571,8 @@ static int __init imx6q_suspend_init(const struct imx6_pm_socdata *socdata)
 		&imx6_suspend,
 		MX6Q_SUSPEND_OCRAM_SIZE - sizeof(*pm_info));
 
+	__arm_iomem_set_ro(suspend_ocram_base, MX6Q_SUSPEND_OCRAM_SIZE);
+
 	goto put_device;
 
 pl310_cache_map_failed: