Re: Booting Debian 10 on powernv POWER9 machine

[Gustavo Romero <gromero@linux.vnet.ibm.com>]

Hi Michael and Lennart,

On 10/17/2019 04:09 PM, Michael Cree wrote:
> On Thu, Oct 17, 2019 at 02:58:37PM -0400, Lennart Sorensen wrote:
> > On Thu, Oct 17, 2019 at 02:57:12PM -0300, Gustavo Romero wrote:
> > > Sorry, I wrote my note super hastily and forgot to mention that I was wondering
> > > about BE specifically. Currently I see kernel 4.16 is used by the installer and
> > > I get a panic regarding a VMX Unavailable Exception on POWER9 powernv (both
> > > baremetal / OPAL and qemu emulated), so I'm wondering if anybody else is
> > > catching that panic too etc. I know BE support for PPC64 was dropped officially
> > > by I understand buildd builders are still building it so there are fresh
> > > packages out there.
> > >
> > > Thanks for replying and for the comments!
> >
> > I don't believe 64 bit powerpc big endian was ever officially released
> > by Debian.  32 bit was but was dropped some time ago.

Got it, the drop was only for 32-bit. Thanks.


> > 64 bit little endian on the other hand is supported.

Yep, I know.


 
> 32-bit BE powerpc and 64-bit BE ppc64 ports are unofficially maintained
> at debian-ports:
>
> https://www.ports.debian.org/
>
> There are installers there.  Only unstable is available.

I could not find the installer's initrd.gz there, just the packages. I don't have
much experience on Debian, but I did some workarounds and was able to get Debian
Bullseye at least booting on POWER9 BE with upstream kernel 5.3:

root@gromero17:~# cat /etc/issue
Debian GNU/Linux bullseye/sid \n \l

root@gromero17:~# lscpu
Architecture:                    ppc64
CPU op-mode(s):                  32-bit, 64-bit
Byte Order:                      Big Endian
CPU(s):                          1
On-line CPU(s) list:             0
Thread(s) per core:              1
Core(s) per socket:              1
Socket(s):                       1
NUMA node(s):                    1
Model:                           2.0 (pvr 004e 1200)
Model name:                      POWER9, altivec supported
L1d cache:                       32 KiB
L1i cache:                       32 KiB
NUMA node0 CPU(s):               0
Vulnerability L1tf:              Not affected
Vulnerability Mds:               Not affected
Vulnerability Meltdown:          Mitigation; RFI Flush
Vulnerability Spec store bypass: Mitigation; Kernel entry/exit barrier (eieio)
Vulnerability Spectre v1:        Mitigation; __user pointer sanitization
Vulnerability Spectre v2:        Vulnerable
root@gromero17:~# uname -a
Linux gromero17 5.3.0 #13 SMP Fri Oct 18 16:45:30 EDT 2019 ppc64 GNU/Linux
root@gromero17:~# ping -c 4 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=50 time=6.98 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=50 time=6.15 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=50 time=6.23 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=50 time=6.29 ms

--- 8.8.8.8 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3006ms
rtt min/avg/max/mdev = 6.154/6.413/6.983/0.332 ms
root@gromero17:~#


Thanks a lot for all the help.

Best regards,
Gustavo