Re: NVMM not working, NetBSD 9x amd64

[Maxime Villard <max%m00nbsd.net@localhost>]

Le 01/05/2020 à 19:13, Chavdar Ivanov a écrit :
> On Fri, 1 May 2020 at 13:59, Rhialto <rhialto%falu.nl@localhost> wrote:
> > On Sun 26 Apr 2020 at 21:39:12 +0200, Maxime Villard wrote:
> > > Maybe I should add a note in the man page to say that you cannot expect a CPU
> > > from before ~2010 to have virtualization support.
> >
> > Or even better, what one should look for in the output of, for example,
> > "cpuctl identify 0". Since I didn't exactly know, I made some guesses
> > and assumed that my cpu ("Intel(R) Core(TM) i3-2120 CPU @ 3.30GHz")
> > did't have the required features (it is from 2009 or so).  But this
> > thread inspired me to modload nvmm, which actually helped, so I found
> > out that it even works on this cpu.

On Intel CPUs the information is hidden in privileged registers that cpuctl
cannot access, so no, it won't be possible.

However the day before I had added clear warnings:

	https://mail-index.netbsd.org/source-changes/2020/04/30/msg116878.html

So now it will tell you what's missing.

> > Of course I immediately tried it with Haiku (the BeOS clone) from
> > https://download.haiku-os.org/nightly-images/x86_64/ and I got mixed
> > results. Once it manages to boot it works fine and nicely fast (much
> > better than without nvmm), but quite often it crashes into its kernel
> > debugger during the first 10 seconds of booting, with different messages
> > (I have seen "General Protection Exception" and "ASSERT failed ...
> > fCPUCount >= 0").  ("qemu-system-x86_64 -accel nvmm -m 2G -cdrom
> > haiku-master-hrev54106-x86_64-anyboot.iso" on a 9.0 GENERIC kernel)

This was a missing filtering in the CPU identification, on CPUs that have SMT,
leading Haiku to believe it had SMT threads that it didn't.

	https://mail-index.netbsd.org/source-changes/2020/05/09/msg117188.html

As far as I can tell, your CPU has SMT.

> I've never used Haiku so far; upon reading this I decided to try it on
> my NetBSD-current laptop with nvmm.
>
> So far, with several attempts, it works with no problem whatsoever,
> directly booting the newest image on the site pointed above.
>
> Another OS to play with...
>
> The host cpu is Intel(R) Core(TM) i7-3820QM CPU @ 2.70GHz, id 0x306a9.

This CPU too has SMT.

Le 01/05/2020 à 20:10, Rhialto a écrit :
> There might well be an improvement between 9.0 and -current, of course.
> It's good to hear that it works for you; I might upgrade to a -current
> kernel.

Overall, no, each improvement in -current is propagated to 9, so you should
get the same results on both (modulo kernel bugs added in places not
related to NVMM).

Le 01/05/2020 à 20:52, Chavdar Ivanov a écrit :
> Earlier I had similar issues with OmniOS under qemu-nvmm - sometimes
> it worked without a problem, sometimes I couldn't even boot. I still
> have no idea why.

Maybe that's the same problem, I'll test.

Maxime