Hi Ryan.
No, this is dead.
Ard's rebuttal was spot on, and unarguable.   The problem needs fixing, but not 
in UEFI.
Please disregard this patch.


>-----Original Message-----
>From: Ard Biesheuvel [mailto:ard.biesheu...@linaro.org]
>Sent: 11 October 2016 20:17
>To: ryan.har...@linaro.org
>Cc: Evan Lloyd; edk2-devel@lists.01.org; Leif Lindholm
>Subject: Re: [edk2] ArmPlatformPkg: Allocate VRAM as
>On 11 October 2016 at 18:44, Ryan Harkin <ryan.har...@linaro.org> wrote:
>> Hi Evan,
>> This was sent to the list with no subject line and I wasn't on CC, so
>> I didn't see it.
>> Are you still using this patch and want it in, i.e. does it need
>> review and test?
>I'm sure it works, but I don't think we should take it.
>RuntimeServicesData can never be released to the OS, so taking an 8MB
>chunk just in case the OS may decide to drive the framebuffer using
>the firmware's protocol rather than via a native driver is not
>something we should have in reference code.
>The GOP protocol is arguably a hack anyway, since the entire protocol
>database and driver tree are torn down after ExitBootServices(), while
>the GOP leaves a live memory range in place that happens to keep
>operating as a framebuffer. If the OS wants to use this protocol
>during normal operation, it should take care to reserve this memory
>region itself.
>I am aware that not all OSes may behave correctly in this regard. This
>is mainly due to the fact that GOP is usually implemented by a PCI
>device, which exposes the framebuffer via a PCI BAR rather than via a
>system memory range.
>> On 4 March 2016 at 15:57,  <evan.ll...@arm.com> wrote:
>>> Code at: https://github.com/EvanLloyd/tianocore/commit/
>>> From: Sami Mujawar <sami.muja...@arm.com>
>>> Date: Thu, 25 Feb 2016 15:07:40 +0000
>>> Subject: [PATCH] ArmPlatformPkg: Allocate VRAM as
>>> The UEFI specification allows the operating system (OS) to use the
>>> Graphics Output Protocol (GOP) in the following scenarios:
>>>  a. as part of the startup process and
>>>  b. prior to loading of a high performance OS graphics driver
>>> If the VRAM is allocated as BootServicesData, then it is unmapped on
>>> exit boot services. This prevents GOP usage by the OS post exit boot
>>> services (the second scenario); as it results in a crash when the VRAM
>>> is accessed.
>>> This patch fixes the issue by allocating VRAM as RuntimeServicesData.
>>> Code at:
>>> Contributed-under: TianoCore Contribution Agreement 1.0
>>> Signed-off-by: Alexei Fedorov <alexei.fedo...@arm.com>
>>> Signed-off-by: Girish Pathak <girish.pat...@arm.com>
>>> Signed-off-by: Sami Mujawar <sami.muja...@arm.com>
>>> Signed-off-by: Evan Lloyd <evan.ll...@arm.com>
>>> ---
>mVExpress.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>> diff --git
>>> index a578467..4ab8862 100644
>>> ---
>>> +++
>>> @@ -133,7 +133,7 @@ LcdPlatformGetVram (
>>>    } else {
>>>      AllocationType = AllocateAddress;
>>>    }
>>> -  Status = gBS->AllocatePages (AllocationType, EfiBootServicesData,
>>> +  Status = gBS->AllocatePages (AllocationType, EfiRuntimeServicesData,
>>>    if (EFI_ERROR(Status)) {
>>>      return Status;
>>>    }
>>> --
>>> 2.7.0
>>> _______________________________________________
>>> edk2-devel mailing list
>>> edk2-devel@lists.01.org
>>> https://lists.01.org/mailman/listinfo/edk2-devel
>> _______________________________________________
>> edk2-devel mailing list
>> edk2-devel@lists.01.org
>> https://lists.01.org/mailman/listinfo/edk2-devel

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