From b0804ed0cadd7e38d94d2f15cdcc0d9695818856 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Tue, 9 May 2017 10:04:30 +0100 Subject: [PATCH] ARM: dts: bcm283x: Reserve first page for firmware The Raspberry Pi startup stub files for multi-core BCM283X processors make the secondary CPUs spin until the corresponding mailbox is written. These stubs are loaded at physical address 0x00000xxx (as seen by the ARMs), but this page will be reused by the kernel unless it is explicitly reserved, causing the waiting cores to execute random code. Use the /memreserve/ Device Tree directive to mark the first page as off-limits to the kernel. See: https://github.com/raspberrypi/linux/issues/1989 Signed-off-by: Phil Elwell Signed-off-by: Eric Anholt Reviewed-by: Eric Anholt --- arch/arm/boot/dts/bcm283x.dtsi | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/boot/dts/bcm283x.dtsi b/arch/arm/boot/dts/bcm283x.dtsi index 35cea3fcaf5c..1ac7c0dc6577 100644 --- a/arch/arm/boot/dts/bcm283x.dtsi +++ b/arch/arm/boot/dts/bcm283x.dtsi @@ -3,6 +3,11 @@ #include #include +/* firmware-provided startup stubs live here, where the secondary CPUs are + * spinning. + */ +/memreserve/ 0x00000000 0x00001000; + /* This include file covers the common peripherals and configuration between * bcm2835 and bcm2836 implementations, leaving the CPU configuration to * bcm2835.dtsi and bcm2836.dtsi. -- 2.39.5