On Thu, 23 Feb 2023 at 06:53, Yuanhao Xie <[email protected]> wrote:
>
> Hi,
>
> Set "Address    = BASE_4GB - 1" first is to ensure the maximum address value 
> is 4GB, since APs will be switched to 32 bit before OS, I mean in the 
> original implementation.
> By the way, in patch 5, only SEV-ES processor keep this limitation, since for 
> the generic processors they keep in 64 bit before handing off the process to 
> OS, and for those 32-bit processors, they don't need this limitation.
>
> Regards,
> Yuanhao
> -----Original Message-----
> From: Gerd Hoffmann <[email protected]>
> Sent: Tuesday, February 21, 2023 5:26 PM
> To: [email protected]; Xie, Yuanhao <[email protected]>
> Cc: Dong, Guo <[email protected]>; Ni, Ray <[email protected]>; Rhodes, Sean 
> <[email protected]>; Lu, James <[email protected]>; Guo, Gua 
> <[email protected]>
> Subject: Re: [edk2-devel] [Patch V2 2/5] UefiCpuPkg: Contiguous memory 
> allocation and code clean-up.
>
>   Hi,
>
> > +  Address    = BASE_4GB - 1;
>
> Why do you set Address here ...
>
> > +  Status = gBS->AllocatePages (
> > +                  AllocateMaxAddress,
> > +                  EfiReservedMemoryType,
> > +                  StackPages+FuncPages,
> > +                  &Address
> > +                  );
>
> ... when it is overridden here anyway?
>

AllocateMaxAddress uses the provided address as the upper bound for
the allocation.


-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#100455): https://edk2.groups.io/g/devel/message/100455
Mute This Topic: https://groups.io/mt/97081030/21656
Group Owner: [email protected]
Unsubscribe: https://edk2.groups.io/g/devel/unsub [[email protected]]
-=-=-=-=-=-=-=-=-=-=-=-


Reply via email to