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From: "Ard Biesheuvel" <ardb@kernel.org>
Date: Wed, 19 Oct 2022 10:57:02 +0200
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Subject: Re: [edk2-devel] [PATCH v7 0/7] Add safe unaccepted memory behavior
To: devel@edk2.groups.io, dionnaglaze@google.com
Cc: "Ni, Ray" <ray.ni@intel.com>, "Xu, Min M" <min.m.xu@intel.com>, 
	Gerd Hoffmann <kraxel@redhat.com>, James Bottomley <jejb@linux.ibm.com>, 
	Tom Lendacky <Thomas.Lendacky@amd.com>, "Yao, Jiewen" <jiewen.yao@intel.com>, 
	"Aktas, Erdem" <erdemaktas@google.com>, Andrew Fish <afish@apple.com>, 
	"Kinney, Michael D" <michael.d.kinney@intel.com>
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On Fri, 14 Oct 2022 at 23:30, Dionna Glaze via groups.io
<dionnaglaze=google.com@groups.io> wrote:
>
> >
> > Can OsIndicationsSupported UEFI variable provide the similar functionality?
> >
>
> Similar, but not the same. If we use a UEFI variable, its value will
> persist across boots.

That assumes the variable is non-volatile, but I suppose we could use
a volatile variable [other than OsIndications] as well.

> This can be fine if you only boot one OS, but if
> you have two where one supports unaccepted memory and the other
> doesn't then you have a problem.
> The protocol here is specific to the code that will be calling
> ExitBootServices, and thus won't mess up another OS once we reboot and
> select it.
>
> --
> -Dionna Glaze, PhD (she/her)
>
>
> 
>
>