Re: [PATCH v2] Grab the EFI System Resource Table and check it

[Luca Fancellu <Luca.Fancellu@arm.com>]

> On 5 Apr 2022, at 20:21, Stefano Stabellini <sstabellini@kernel.org> wrote:
> 
> On Mon, 4 Apr 2022, Luca Fancellu wrote:
>>> On 2 Apr 2022, at 00:14, Demi Marie Obenour <demi@invisiblethingslab.com> wrote:
>>> 
>>> The EFI System Resource Table (ESRT) is necessary for fwupd to identify
>>> firmware updates to install.  According to the UEFI specification §23.4,
>>> the table shall be stored in memory of type EfiBootServicesData.
>>> Therefore, Xen must avoid reusing that memory for other purposes, so
>>> that Linux can access the ESRT.  Additionally, Xen must mark the memory
>>> as reserved, so that Linux knows accessing it is safe.
>>> 
>>> See https://lore.kernel.org/xen-devel/20200818184018.GN1679@mail-itl/T/
>>> for details.
>>> 
>>> Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
>> 
>> Hi,
>> 
>> I’ve tested the patch on an arm machine booting Xen+Dom0 through EFI, unfortunately
>> I could not test the functionality.
> 
> I understand you couldn't test ESRT but did the basic Xen+Dom0 boot via
> EFI on ARM work?

Yes, I realise now I should have added *and it works* before the comma, without it the sentence is
misleading.

Cheers,
Luca