PT32_[GS]ETXMMREGS for amd64 (Was: netbsd32_{,u}int64 in sys/types.h for compat/sys/siginfo.h)

[Rin Okuyama <rokuyama.rk%gmail.com@localhost>]

Hi, thank you for your review!

On 2019/11/22 0:48, Kamil Rytarowski wrote:
> On 21.11.2019 10:49, Rin Okuyama wrote:
...
> > I wrote a draft version of patch which adds PT32_[GS]ETXMMREGS support:
> >
> > http://www.netbsd.org/~rin/amd64-PT32_GSETXMMREGS-20191121.patch
> >
> > With this patch, XMM-related tests pass for COMPAT_NETBSD32 on amd64.
> >
> > Some remarks:
> >
> > (1) PT_[GS]ETXMMREGS ptrace(2) commands are added to <machine/ptrace.h>.
> >      These are only used for COMPAT_NETBSD32, and not exposed to userland.
>
> This is correct.
> We don't want to export XMMREGS to amd64 users.
>
> Pleae remove /* */ from this part:
>
> +/*
> +	"PT_GETXMMREGS", \
> +	"PT_SETXMMREGS"
> + */

Yes, I will.

> This will allow ktruss and related software to have meaningful form for
> compat32 ptracing.
>
> > (2) COMPAT_NETBSD32 codes are called from process_machdep.c via
> >      module_hook framework. This may be too much though...
>
> I have no opinion here.

Now, Paul and I are discussed how to improve the usage of module_hook.
I will update this part in accordance with his advice.

> > Comments?
>
> I will leave this to be reviewed by mgorny@. Adding him to CC.

I see. Hi, mgorny@. Please look into it!
> > http://www.netbsd.org/~rin/amd64-PT32_GSETXMMREGS-20191121.patch

> > > Also, it seems that some COMPAT_NETBSD32 related codes for amd64 need to
> > > be cleaned up. For example, there remain COMPAT_NETBSD32 codes in
> > > amd64/process_machdep.c, that are no longer used:
> > >
> > > https://nxr.netbsd.org/xref/src/sys/arch/amd64/amd64/process_machdep.c#129
> > >
> > > https://nxr.netbsd.org/xref/src/sys/arch/amd64/amd64/process_machdep.c#183
> > >
> > > ...
> > >
> > > I will examine them too.
> >
> > This was my misunderstanding. These codes are used when tracer is 64-bit
> > and traced is 32-bit. Don't know whether this is useful though...
> >
> > Thanks,
> > rin
>
> Maxime added it. If you want to change it, please consult with maxv@.

OK. It must be useful for a tracer capable for both 64- and 32-bit
processes (although, we also need to provide x87-style fpregs for
64-bit tracer in some way).

Thanks,
rin