RE: [PATCH v2 01/19] xen/x86: remove "depends on !PV_SHIM_EXCLUSIVE"

["Penny, Zheng" <penny.zheng@xxxxxxx>]

[Public]

Hi,

> -----Original Message-----
> From: Jan Beulich <jbeulich@xxxxxxxx>
> Sent: Monday, March 31, 2025 2:30 PM
> To: Stefano Stabellini <sstabellini@xxxxxxxxxx>; Penny, Zheng
> <penny.zheng@xxxxxxx>
> Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx; Huang, Ray <Ray.Huang@xxxxxxx>;
> Andrew Cooper <andrew.cooper3@xxxxxxxxxx>; Roger Pau Monné
> <roger.pau@xxxxxxxxxx>; Anthony PERARD <anthony.perard@xxxxxxxxxx>; Orzel,
> Michal <Michal.Orzel@xxxxxxx>; Julien Grall <julien@xxxxxxx>
> Subject: Re: [PATCH v2 01/19] xen/x86: remove "depends
> on !PV_SHIM_EXCLUSIVE"
>
> On 29.03.2025 00:56, Stefano Stabellini wrote:
> > On Wed, 26 Mar 2025, Penny Zheng wrote:
> >> We intend to remove all "depends on !PV_SHIM_EXCLUSIVE" (also the
> >> functionally equivalent "if !...") in Kconfig file, since negative
> >> dependancy will badly affect allyesconfig.
> >> This commit is based on "x86: provide an inverted Kconfig control for
> >> shim-exclusive mode"[1]
> >>
> >> [1]
> >> https://lists.xen.org/archives/html/xen-devel/2023-03/msg00040.html
> >>
> >> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>
> Where's this coming from, if I may ask?
>

I said in the commit message, this commit is based on your commit "x86: provide 
an inverted Kconfig control for
shim-exclusive mode"[1].
So I think I shall add-in the original author, if it is not the rule, I'll 
remove it.

> >> Signed-off-by: Penny Zheng <Penny.Zheng@xxxxxxx>
> >> ---
> >>  xen/arch/x86/Kconfig      | 6 ++----
> >>  xen/arch/x86/hvm/Kconfig  | 1 -
> >>  xen/drivers/video/Kconfig | 4 ++--
> >>  3 files changed, 4 insertions(+), 7 deletions(-)
> >>
> >> diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig index
> >> 18efdb2e31..1e5df84b25 100644
> >> --- a/xen/arch/x86/Kconfig
> >> +++ b/xen/arch/x86/Kconfig
> >> @@ -137,7 +137,6 @@ config XEN_IBT
> >>
> >>  config SHADOW_PAGING
> >>    bool "Shadow Paging"
> >> -  default !PV_SHIM_EXCLUSIVE
> >>    depends on PV || HVM
> >>    help
> >>
> >> @@ -169,7 +168,6 @@ config BIGMEM
> >>  config TBOOT
> >>    bool "Xen tboot support (UNSUPPORTED)"
> >>    depends on INTEL && UNSUPPORTED
> >> -  default !PV_SHIM_EXCLUSIVE
> >>    select CRYPTO
> >>    help
> >>      Allows support for Trusted Boot using the Intel(R) Trusted
> >> Execution @@ -279,10 +277,11 @@ config PV_SHIM_EXCLUSIVE
> >>      Build Xen in a way which unconditionally assumes PV_SHIM mode.  This
> >>      option is only intended for use when building a dedicated PV Shim
> >>      firmware, and will not function correctly in other scenarios.
> >> +    Features, like tboot, shadow page, VGA, HVM, Hyper-V Guest, etc,
> >> +    are unavailable in shim-exclusive mode.
> >
> > I don't know if we want to add these two lines or not. Either way:
> >
> > Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
>
> I don't think we should add that. It's also wrong for shadow in the first 
> place (where
> it was a default only anyway, not a dependency).

Ack, I'll remove

>
> Jan