RE: [PATCH 11/12] gdb, gdbarch: Introduce gdbarch method to get the shadow stack pointer.

["Schimpe, Christina" <christina.schimpe@intel.com>]

> -----Original Message-----
> From: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
> Sent: Saturday, February 15, 2025 4:45 AM
> To: Schimpe, Christina <christina.schimpe@intel.com>
> Cc: gdb-patches@sourceware.org
> Subject: Re: [PATCH 11/12] gdb, gdbarch: Introduce gdbarch method to get
> the shadow stack pointer.
> 
> Hello Christina,
> 
> Thiago Jung Bauermann <thiago.bauermann@linaro.org> writes:
> 
> > "Schimpe, Christina" <christina.schimpe@intel.com> writes:
> >
> >> Would something like that be acceptable as well?
> >>
> >> Method(
> >>       comment="""
> >> If possible, return the shadow stack pointer. On some architectures,
> >> the shadow stack pointer is available even if the feature is
> >> disabled.  To return the shadow stack enablement state configure
> SHADOW_STACK_ENABLED.
> >>   """,
> >> type="std::optional<CORE_ADDR>",
> >> name="get_shadow_stack_pointer",
> >> params=[("bool &", "shadow_stack_enabled")],
> >> predefault="default_get_shadow_stack_pointer",
> >> invalid=False,
> >> )
> >
> > Yes, this looks good.
> 
> I was rebasing my Guarded Control Stack code on top of this series, and
> noticed that I will need to access the thread's regcache for the aarch64
> implementation of this gdbarch method. Then I noticed that the x86_64
> version also needs it, and calls "get_thread_regcache (inferior_thread ())".
> It would be better to pass the regcache as an argument instead.

Hi Thiago, 

Do you mean instead or in addition?
I thought you also need the parameter ("bool &", "shadow_stack_enabled").

Christina
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