DOS ain't dead - PCI phased out?

PCI phased out? (Announce)

posted by Rugxulo , Usono, 16.03.2011, 04:58

> > 16-bit covers real mode (8086 - MS-DOS) and pmode (286 - OS/2 1.x), two
> > entirely different things (though they both use segmentation).
>
> > I've heard conflicting reports (Ross Ridge, Bart Oldemann), so I'm not
> > entirely sure if the cpu (long mode) itself or just the 64-bit OSes
> (Win64,
> > Linux64) refuse to support one or both of those.
>
> I've searched about this, and long mode supports 16-bit protected mode, but
> not real mode.
>
> There are also some hints that this goes for pure application code only,
> and that operating system (and I assume extenders) level code might not
> work (e.g. the unavailability of certain TSS features in long mode).
>
> Since afaik win16 apps are pmode, they may indeed run technically, but
> win64 doesn't support it.
>
> Afaik Linux never had support for 16-bit pmode.

I now hear that AMD's SVM / Pacifica (only, and not Intel) supports "Paged real mode". Xen claims to support this now.

On the opposite side, it seems that Intel's VT-X on Westmere (32nm Nehalem) supports "Unrestricted guest execution" (real mode, big real mode).

So I guess "native" 16-bit support isn't available but under a hypervisor there is (or should be) some support. VirtualBox allegedly supports one of these, maybe both (??) since 3.2.0. But I haven't tested any of those (yet?).

P.S. DOSEMU x86-64 does use the phrase "JIT code generation" (see /etc/dosemu/dosemu.conf) for what it does, but I don't know the details (and "vm86sim" supposedly disables it for more accurate emulation). I have no idea (and somehow doubt) if it uses either of these hypervisor technologies.

BTW, I did try Cash Invaders (16-bit pmode, BP7) with the default setup (DOSEMU under Fedora 14 x86-64), but it didn't run at all, and actually it crashed the "DOS in a box". But the few other normal things I tried worked fine. YMMV. (DOSBox works fine, though. Even PC-BSD apparently has that.)

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Complete thread:

PCI phased out? - marcov, 09.02.2011, 12:51 (Announce)
- PCI phased out? - RayeR, 09.02.2011, 16:24
  - PCI phased out? - marcov, 10.02.2011, 16:02
    - PCI phased out? - RayeR, 10.02.2011, 17:57
      - PCI phased out? - marcov, 10.02.2011, 21:10
        PCI phased out? - RayeR, 11.02.2011, 00:25
        PCI phased out? - marcov, 11.02.2011, 10:56
        PCI phased out? - RayeR, 12.02.2011, 02:34
        PCI phased out? - marcov, 12.02.2011, 12:45
        PCI phased out? - Rugxulo, 12.02.2011, 21:28
        PCI phased out? - DOS386, 13.02.2011, 06:02
        PCI phased out? - RayeR, 13.02.2011, 16:11
        PCI phased out? - DOS386, 14.02.2011, 09:27
        PCI phased out? - marcov, 14.02.2011, 10:29
        NTVDM speed (or lack thereof) - Ninho, 15.02.2011, 12:26
        NTVDM speed (or lack thereof) - Rugxulo, 15.02.2011, 14:26
        NTVDM speed (or lack thereof) - marcov, 15.02.2011, 14:33
        NTVDM speed (or lack thereof) - Ninho, 15.02.2011, 20:27
        NTVDM speed (or lack thereof) - Rugxulo, 15.02.2011, 23:21
        NTVDM speed (or lack thereof) - marcov, 16.02.2011, 09:24
        NTVDM speed (or lack thereof) - Ninho, 16.02.2011, 20:04
        NTVDM speed (or lack thereof) - RayeR, 16.02.2011, 01:50
        NTVDM speed (or lack thereof) - Rugxulo, 16.02.2011, 02:24
        NTVDM speed (or lack thereof) - RayeR, 16.02.2011, 10:41
        NTVDM speed (or lack thereof) - rr, 17.02.2011, 20:33
        PCI phased out? - RayeR, 14.02.2011, 15:45
        PCI phased out? - marcov, 15.02.2011, 13:40
        PCI phased out? - RayeR, 15.02.2011, 15:15
        PCI phased out? - marcov, 15.02.2011, 18:43
        PCI phased out? - RayeR, 15.02.2011, 19:46
        PCI phased out? - marcov, 16.02.2011, 10:36
        PCI phased out? - RayeR, 16.02.2011, 12:22
        PCI phased out? - marcov, 16.02.2011, 15:38
        PCI phased out? - Rugxulo, 16.02.2011, 19:18
        PCI phased out? - marcov, 16.02.2011, 21:22
        PCI phased out? - Rugxulo, 17.02.2011, 02:28
        EOD (was "PCI phased out?") - DOS386, 17.02.2011, 06:44
        PCI phased out? - marcov, 17.02.2011, 19:44
        PCI phased out? - Rugxulo, 18.02.2011, 08:39
        PCI phased out? - marcov, 18.02.2011, 09:30
        PCI phased out? - Rugxulo, 21.02.2011, 07:43
        PCI phased out? - Rugxulo, 08.03.2011, 23:47
        PCI phased out? - Rugxulo, 11.03.2011, 00:06
        PCI phased out? - roytam, 11.03.2011, 07:52
        PCI phased out? - Rugxulo, 17.03.2011, 04:16
        PCI phased out? - Ninho, 19.02.2011, 10:56
        PCI phased out? - Rugxulo, 21.02.2011, 07:15
        PCI phased out? - marcov, 21.02.2011, 14:09
        PCI phased out? - Laaca, 21.02.2011, 14:22
        PCI phased out? - marcov, 21.02.2011, 14:47
        PCI phased out? - roytam, 22.02.2011, 04:26
        PCI phased out? - RayeR, 22.02.2011, 13:29
        PCI phased out? - RayeR, 22.02.2011, 23:44
        PCI phased out? - Ninho, 23.02.2011, 17:39
        PCI phased out? - RayeR, 23.02.2011, 19:47
        PCI phased out? - Ninho, 23.02.2011, 19:56
        PCI phased out? - RayeR, 23.02.2011, 23:27
        PCI phased out? - RayeR, 24.02.2011, 14:37
        PCI phased out? - Rugxulo, 16.03.2011, 04:58
        PCI phased out? - RayeR, 18.02.2011, 14:28
        PCI phased out? - marcov, 18.02.2011, 14:56
        PCI phased out? - roytam, 29.01.2015, 03:45