Re: [PATCH v3 2/9] xen: reuse x86 EFI stub functions for Arm

[Julien Grall <julien@xxxxxxx>]

Hi Wei,

On 19/05/2022 03:36, Wei Chen wrote:
> > -----Original Message-----
> > From: Jan Beulich <jbeulich@xxxxxxxx>
> > Sent: 2022年5月18日 21:05
> > To: Wei Chen <Wei.Chen@xxxxxxx>
> > Cc: nd <nd@xxxxxxx>; Stefano Stabellini <sstabellini@xxxxxxxxxx>; Julien
> > Grall <julien@xxxxxxx>; Bertrand Marquis <Bertrand.Marquis@xxxxxxx>;
> > Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>; Andrew Cooper
> > <andrew.cooper3@xxxxxxxxxx>; Roger Pau Monné <roger.pau@xxxxxxxxxx>; Wei
> > Liu <wl@xxxxxxx>; Jiamei Xie <Jiamei.Xie@xxxxxxx>; xen-
> > devel@xxxxxxxxxxxxxxxxxxxx
> > Subject: Re: [PATCH v3 2/9] xen: reuse x86 EFI stub functions for Arm
> >
> > On 11.05.2022 03:46, Wei Chen wrote:
> > > x86 is using compiler feature testing to decide EFI build
> > > enable or not. When EFI build is disabled, x86 will use an
> > > efi/stub.c file to replace efi/runtime.c for build objects.
> > > Following this idea, we introduce a stub file for Arm, but
> > > use CONFIG_ARM_EFI to decide EFI build enable or not.
> > >
> > > And the most functions in x86 EFI stub.c can be reused for
> > > other architectures, like Arm. So we move them to common
> > > and keep the x86 specific function in x86/efi/stub.c.
> > >
> > > To avoid the symbol link conflict error when linking common
> > > stub files to x86/efi. We add a regular file check in efi
> > > stub files' link script. Depends on this check we can bypass
> > > the link behaviors for existed stub files in x86/efi.
> > >
> > > As there is no Arm specific EFI stub function for Arm in
> > > current stage, Arm still can use the existed symbol link
> > > method for EFI stub files.
> > Wouldn't it be better to mandate that every arch has its stub.c,
> > and in the Arm one all you'd do (for now) is #include the common
> > one? (But see also below.)
> Personally, I don't like to include a C file into another C file.
Same here. I know we already use it in EFI but I am not in favor to add 
more of them.
Cheers,

--
Julien Grall