Re: [Qemu-devel] Help needed: Sparc 64, kernel panic

[Ajallooiean Hossein <hossein.ajallooiean@epfl.ch>]

Thanks a lot.

I really appreciate this.
________________________________________
From: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Sent: Monday, May 1, 2017 9:06 PM
To: Ajallooiean Hossein; qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Help needed: Sparc 64, kernel panic

On 23/04/17 00:42, Ajallooiean Hossein wrote:

Hi Ajallooiean,

> Hi Mark,
>
> Thanks a lot for this. - it did work!
>
> So, now im wondering how did you install the iso on disk?
>
> would you mind sharing your command line for the install please? and hacks if any

I simply went for something along the lines of:

./qemu-system-sparc64 -hda deb90.qcow2 -cdrom
debian-9.0-sparc64-NETINST-1.iso -boot d -nographic

i.e. no virtio devices and using the in-built device emulation. I do
have some alpha patches that add virtio support to OpenBIOS but they are
definitely not ready for production yet.

> i am now able to install and boot, but my boot hang after this line "[   22.559491] [TTM] Initializing pool allocator" - inside user space. - I did blacklist bochs_drm for installing as such "-append 'modprobe.blacklist=bochs_drm'".

Once I installed the image, I restarted QEMU as normal but this time
booting from the qcow2 image i.e.

./qemu-system-sparc64 -hda deb90.qcow2 -cdrom
debian-9.0-sparc64-NETINST-1.iso -nographic

Then at the SILO "boot: " prompt I typed:

Linux modprobe.blacklist=bochs_drm

That got me to a terminal login at which point I created the following
file as /etc/modprobe.d/bochs_drm.conf:

blacklist bochs_drm

I then did an update-initramfs rebooted as normal, since with the module
blacklisted there is no need to enter any custom parameters at the SILO
boot prompt and I can simply hit Enter.

> also, i have a couple of questions if you dont mind responding to them. - ill appreciate this a lot:
> 1- did you use virtio for your install? i.e. not using the "-cdrom" command and blacklisting the pata_cmd64x and also providing your own virtio device (/dev/vdb)?
>     - i used this link for hints on how to install with virtio http://tyom.blogspot.ch/2013/03/debiansparc64-wheezy-under-qemu-how-to.html

No, I just used the slower in-built CDROM emulation.

> 2- i see that you used ext3 for your OS install, isnt that slower than ext4? -again im referencing this: http://tyom.blogspot.ch/2013/03/virtio-performance-and-filesystems.html

>From memory the installer insisted that /boot needed to be an ext3
partition in order to work with SILO which is why I chose it.

> 3- also, im noticing that you didnt define root=/dev/sda or root=/dev/vda1 for when your running qemu. and when im running your image i have to do that, otherwise ill get to the initramfs only. is there a trick behind this?

No, it just seems to work for me with the inbuilt CDROM? However if you
switch to using my image with virtio then you'll have to tweak
/etc/fstab to use /dev/vda* rather than /dev/sda* devices and rebuild
the initramfs once again.

> 4- i dont see you defining a kernel and initrd? is there a reason for this? if i just use your cmd line, ill get this: also, are you extracting the kernel and initrd from the image or the iso?
>
> OpenBIOS for Sparc64
> Configuration device id QEMU version 1 machine id 0
> kernel cmdline
> CPUs: 1 x SUNW,UltraSPARC-IIi
> UUID: 00000000-0000-0000-0000-000000000000
> Welcome to OpenBIOS v1.1 built on Mar 15 2017 19:37
>   Type 'help' for detailed information
> Trying disk:a...
> Not a bootable ELF image
> Loading a.out image...
> Loaded 7680 bytes
> entry point is 0x4000
> SILO Version 1.4.14
> boot:

Right - all you need to do here is hit Enter and boot will continue.
Since I'm not using virtio I'm letting SILO do the work here. Once
you've blacklisted bochs_drm and rebuilt the initramfs with everything
setup then you should be able to copy them from the resulting image and
boot them directly in QEMU using -kernel and -initrd.


ATB,

Mark.