Re: debian bootup hangs on qemu-system-mips64el

[Jun Sun]

See below.

On Sun, Jan 12, 2020 at 11:58 AM Aurelien Jarno <address@hidden> wrote:
>
> Hi,
>
> On 2020-01-12 11:34, Jun Sun wrote:
> > Are you sure QEMU/MIPS does not support SMP?  Below link written in
> > 2016 clearly shows something was working then.
> >
> > https://www.mips.com/blog/how-to-run-smp-linux-in-qemu-on-a-mips64-release-6-cpu/
>
> It's not supported for the malta/mips64r2 combination you are trying to
> use. It's clearly possible that it is supported for mips64r6, but it's a
> different instruction set, so you can't run a standard Debian
> distribution on it.
>

How do I specify mips64r6 cpu to start qemu?  A simple cpu listing
below shows no such CPU.  If mips64r6 is indeed supported with SMP, I
would think mips64r2 userland should run fine.

$ qemu-system-mips64el -cpu ?
MIPS '4Kc'
MIPS '4Km'
MIPS '4KEcR1'
MIPS '4KEmR1'
MIPS '4KEc'
MIPS '4KEm'
MIPS '24Kc'
MIPS '24KEc'
MIPS '24Kf'
MIPS '34Kf'
MIPS '74Kf'
MIPS 'M14K'
MIPS 'M14Kc'
MIPS 'P5600'
MIPS 'mips32r6-generic'
MIPS 'R4000'
MIPS 'VR5432'
MIPS '5Kc'
MIPS '5Kf'
MIPS '20Kc'
MIPS 'MIPS64R2-generic'
MIPS '5KEc'
MIPS '5KEf'
MIPS 'I6400'
MIPS 'Loongson-2E'
MIPS 'Loongson-2F'
MIPS 'mips64dspr2'

> > Also, as Lixing mentioned in our private exchange, there is SMP
> > support for loongson.  Lixing, I assume loongson SMP support is
> > already merged in QEMU repo, right?  Can you point out the relevant
> > source code directories?
>
> Lixing mentioned virtualization. In that case it is indeed supported
> like on other mips64r5 CPUs. For that you need to use add the -enable-kvm
> option to the qemu command.

I'm not sure if loongson support has to be kvm.  Maybe Lixing can clarify.