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Subject: Re: [PATCH V2] ARM: dts: bcm283x: Reserve first page for firmware
To: Eric Anholt <eric@anholt.net>, Phil Elwell <phil@raspberrypi.org>,
        Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
        Russell King <linux@armlinux.org.uk>,
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References: <b6aef857-1454-7931-2c60-6d7b55b7a0a8@raspberrypi.org>
 <8737cenfhc.fsf@eliezer.anholt.net>
From: Florian Fainelli <f.fainelli@gmail.com>
Message-ID: <bdc05058-f65b-da08-0cf5-51aa1f97852e@gmail.com>
Date: Tue, 9 May 2017 09:52:53 -0700
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On 05/09/2017 09:48 AM, Eric Anholt wrote:
> Phil Elwell <phil@raspberrypi.org> writes:
> 
>> The Raspberry Pi startup stub files for multi-core BCM27XX 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 <phil@raspberrypi.org>
> 
> This looks great.  We're currently in the merge window, so I can't
> generate a new bcm2835-dt-next yet, but I'll pick this patch up when I
> do.
> 
> Thanks for submitting upstream!

Considering that this is a fix, we could actually squeeze it in the
devicetree/fixes branch and we could submit those as soon as v4.12-rc1
is tagged, your call.
-- 
Florian