Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 2 Aug 2023 17:25:29 -0700
From:      Mark Millard <marklmi@yahoo.com>
To:        Warner Losh <imp@bsdimp.com>
Cc:        Current FreeBSD <freebsd-current@freebsd.org>, FreeBSD ARM List <freebsd-arm@freebsd.org>
Subject:   Re: sys/modules/Makefile and MACHINE_ARCH vs arm64 (in use) vs aarch64 (not in use) VS. man arch; also COMPAT_FREEBSD32_ENABLED use
Message-ID:  <D1A6668B-4E6A-44E0-9A2A-69495BD91C41@yahoo.com>
In-Reply-To: <2B0FE8B1-5E53-4E70-9792-15A8E423CA33@yahoo.com>
References:  <B8EB365B-414B-4932-A6F0-7A52733607C5.ref@yahoo.com> <B8EB365B-414B-4932-A6F0-7A52733607C5@yahoo.com> <CANCZdfoRGUANSqWhhC=OOpEPc8zO3YkChKeqJS_NX6Cqn3_AjA@mail.gmail.com> <2B0FE8B1-5E53-4E70-9792-15A8E423CA33@yahoo.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Aug 2, 2023, at 12:56, Mark Millard <marklmi@yahoo.com> wrote:

> On Aug 2, 2023, at 11:16, Warner Losh <imp@bsdimp.com> wrote:
>=20
>> Those all look wrong to me.
>>=20
>> Warner=20
>>=20
>> On Wed, Aug 2, 2023, 11:27 AM Mark Millard <marklmi@yahoo.com> wrote:
>> man arch reports:
>>=20
>>           MACHINE       MACHINE_CPUARCH       MACHINE_ARCH
>>           arm64         aarch64               aarch64
>> . . .
>>           arm           arm                   armv6, armv7
>>=20
>> So I'd not expect arm64 in MACHINE_ARCH . But
>> sys/modules/Makefile has (from a grep for MACHINE_ARCH):
>>=20
>> .if ${MACHINE_ARCH} =3D=3D "amd64" || ${MACHINE_ARCH} =3D=3D "arm64"
>> .if ${MACHINE_ARCH} =3D=3D "amd64" || ${MACHINE_ARCH} =3D=3D "arm64" =
|| ${MACHINE_ARCH:Mpowerpc64*}
>>=20
>>=20
>> Another issue may be that COMPAT_FREEBSD32_ENABLED is only
>> put to use in the Makefile for MACHINE_CPUARCH being i386
>> or amd64 :
>>=20
>> .if ${MACHINE_CPUARCH} =3D=3D "i386" || ${MACHINE_CPUARCH} =3D=3D =
"amd64"
>> _agp=3D           agp
>> .if ${MACHINE_CPUARCH} =3D=3D "i386" || =
!empty(COMPAT_FREEBSD32_ENABLED)
>> . . .
>=20
>=20
> I'll note that, for example, i386 vs. armv7 do not match
> for some struct md_ioctl field offsets and the overall
> size.

Turns out no member offsets were different but the size
was: just differing tail padding in the structure. Still
it means some conditional differences across i386 and
armv7. (I've no clue if the 32-bit powerpc lib32/chroot
handling is working on powerpc64 vs. not. So I make no
claims relative to such.)

> Mike Karels is looking at getting struct md_ioctl32
> correctly matching each of of the contexts: i386, (32-bit)
> powerpc, and armv7.
>=20
> I do not know if there are other COMPAT_FREEBSD32 adjustments
> needed for differences in memory layout across the 3 (i386,
> powerpc, armv7). md_ioctl I learned about via kyua test runs
> and looking at the background for some things it reported for
> armv7.
>=20
> I've not found a clear indication of what is expected to work
> for chroot/lib32 vs. what is not expected to work. It seems
> one must look in the code and see if one finds conditional
> material based, in part, on COMPAT_FREEBSD32. It might also
> be that COMPAT_FREEBSD32 for i386 vs. armv7 vs. powerpc
> might not be intending identical coverage for all I know.
> So seeing COMPAT_FREEBSD32 might not be enough to know the
> intent.


=3D=3D=3D
Mark Millard
marklmi at yahoo.com




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?D1A6668B-4E6A-44E0-9A2A-69495BD91C41>