Menu-based installer unusable through noVNC

I’m in the process of setting up a Guix VPS with arpnetworks.com.

There seems to be some conflict between the “graphical” installer’s idea

of the console size and VNC’s (which appears to be noVNC

https://novnc.com/info.html).As you can see in the attached screenshot,

the screen is cropped on all sides, particularly making the menu choices

unviewable.

Not sure if relevant, but the console goes through a successful mode switch

earlier in the booting process, where the VNC display size changes. Seems

like that should happen again when the menus start, but it doesn’t.

I’ve run other installers through noVNC successfully so there’s a good

chance this is a Guix issue, can’t say for sure though.

Hello,

Robert Vollmert <rob@vllmrt.net> skribis:

I’ve never used noVNC, but doesn’t it allow you to zoom out or

something? The kernel (KMS) knows what it’s doing, so it seems to me

that the problem is that noVNC doesn’t realize what the actual screen

size is. Does the Internet have something to say wrt. noVNC vs. kmscon?

BTW, for your VPS, wouldn’t it be easier to bypass the installation

altogether? That is, you write a config that you want to use, you

create a QCOW2 image or whatever is suitable for your VPS, and you boot

that directly.

Thanks,

Ludo’.

Hello Ludo,

thanks for looking into this.

I don’t seem to get any controls to resize the display; in previous

situations it has seemed to switch modes correctly automatically. That

said, I’m happy to believe that the bug is with noVNC — I’ve reported

it with arpnetworks and will pass it on to noVNC once I know which

version is running.

That’s a nice idea; it turns out that this provider does not appear to

give access to the disk images.

Thanks,

Robert

Robert Vollmert <rob@vllmrt.net> skribis:

Alright, let us know how it goes so we can happily close the bug. :-)

Thanks,

Ludo’.

It turns out arpnetworks are running an older forked version of noVNC,

so this might well have been fixed in the meantime. Not solved, but I

don’t intend to pursue this further at this point, will close. At least

it’s on record if it shows up again.

Cheers

Rob

Hi,

Robert Vollmert <rob@vllmrt.net> skribis:

OK, thanks for investigating!

Ludo’.

Reopened.

On Mon, 3 Jun 2019 11:35:17 +0200

Robert Vollmert <rob@vllmrt.net> wrote:

Today I installed Guix on a Server which uses Guacamole as a web-based

VNC-client according to the HTML code, see

I also had the problem that the screen of the installer was too small,

I'm attaching two screenshots: Of the normal GRUB startup and the

unreadable installer.

I solved it by hitting CTRL-ALT-F3 through the soft-keyboard and

installing it manually: In this console, everything looked fine.

Björn

Hi,

Björn Höfling <bjoern.hoefling@bjoernhoefling.de> skribis:

I think Robert concluded that the bug was in noVNC.

What we’d need is either something to fix on our side (but there’s

apparently nothing), or something to report to noVNC, or a workaround we

could have on our side specifically for this use case.

Do you have anything in mind along these lines?

Thanks,

Ludo’.

Hi,

Rather, I couldn’t prove the bug was anywhere else.

It seems noVNC isn’t involved here, though, with the only clearly common

factor being Guix, so maybe the bug is there after all? (At least, as

far as I can tell, Guacamole does not involve noVNC.)

Robert

On Tue, 25 Jun 2019 16:09:48 +0200

Robert Vollmert <rob@vllmrt.net> wrote:

Guacamole and noVNC have no common roots, AFAIK. So, with a different

VNC-Software showing the same problems, I decided to re-open this bug,

though I have no proof that it is really a Guix-Problem. At least

people who want to install Guix would be annoyed and might run away. As

Robert said, he didn't experience this with any other Distro, that could

be a hint we are doing something wrong here.

I guess you (Ludovic) have tried the installer with QEMU and its

VNC-Server, maybe even with different VNC-clients?

We could try different setups in that directions.

We could look extensively at the code with the mode switches and compare

it with specs about mode-switching? Until now, I have no knowledge in

that area.

Björn

On Tue, Jun 25, 2019 at 05:06:03PM +0200, Bj�rn H�fling wrote:

It works with

qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm -drive file=Downloads/guix-system-install-1.0.1.x86_64-linux.iso -vnc :0

as the VNC server and vinagre as the VNC client.

Sadly novnc and guacamole clients are not packaged. I do not know if

your errors are with the server or the client side.

Regards,

Florian

I just gave my VPS another try; it turns out I can connect directly

to their VNC server. Using the macos built in VNC client I have the

same problem as before, so it appears to not be a client side issue.

The connection is titled “QEMU (server-specific-stuff)”, so this is

probably also a QEMU VNC server.

Hello,

Björn Höfling <bjoern.hoefling@bjoernhoefling.de> skribis:

I agree that this is a problem, I’m trying to see what we could do. :-)

We’re just using “normal” kernel functionality (KMS), so it’s not

obvious to me that Guix itself is doing something wrong. My guess is

that other distros don’t use kmscon and thus don’t trigger this

particular issue.

I haven’t tried this, but I agree it’d be a good thing to do!

You mean kmscon, right?

Thanks,

Ludo’.

On Tue, 25 Jun 2019 17:54:39 +0200

"pelzflorian (Florian Pelz)" <pelzflorian@pelzflorian.de> wrote:

I can confirm it works with vinagre, jvncviewer and guacamole.

What's the conclusion? Maybe that Guix is fine and the VNC-clients are

also fine. It might just be a matter of configuration or using an older

version with bugs?

For the record:

I started qemu slightly differently:

qemu-system-x86_64 -monitor stdio -m 1024 -smp 1 -enable-kvm -cdrom guix-system-install-1.0.1.x86_64-linux.iso -vnc :0

In that way, I have the QEMU console in my terminal and I can call the

"system_reset" command: I suspected that the bug would only appear when

the VNC-Client is connected WHILE the installer start up. Usually the

startup would be fast and the VNC-client connects only when the

installer is already visible.

I installed the guacamole daemon via Ubuntu, using Version

0.9.9-2build1.

I used Tomcat 9.0.21 with guacamole-1.0.0.war, setting up a

~/.guacamole folder (called GUACAMOLE_HOME) with these config files:

$ cat guacamole.properties

guacd-hostname=localhost

guacd-port=4822

guacd-ssl=false

$ cat user-mapping.xml

<user-mapping>

<!-- Per-user authentication and config information -->

<authorize username="guix" password="guix">

<protocol>vnc</protocol>

<param name="hostname">localhost</param>

<param name="port">5900</param>

<!--<param name="password">VNCPASS</param>-->

</authorize>

</user-mapping>

Then I can start up tomcat, go to localhost:9999/guacamole, log in

as user "guix" and directly see the CORRECT installer.

When rebooting, I see correctly the grub startup screen, bootup and

I will see the correct installer, no truncations.

I tried the same with client-versions 0.9.10 and 0.9.14: OK.

I built the server in version 0.9.14, I was able to connect the client

with the server, but then nothing happened. Maybe I missed some

configure flag? Gave up here.

Björn

Lemma: It might not be too hard to package guacd. The client might be

harder, as it uses Maven as a build system.

It seems I can rule that out. I see the bug also when disconnecting directly

after the grub screen and reconnecting after some time. Similarly, the

screen is still messed up when I disconnect and connect again while the

menu is showing.

On Wed, Jun 26, 2019 at 06:51:41PM +0200, Björn Höfling wrote:

Passing “-vga cirrus” reduces the display size.

The command “man qemu” says:

-vga type

Select type of VGA card to emulate. Valid values for type

are

cirrus

Cirrus Logic GD5446 Video card. All Windows versions

starting from Windows 95 should recognize and use

this graphic card. For optimal performances, use 16

bit color depth in the guest and the host OS. (This

card was the default before QEMU 2.2)

So presumably the VPS is using an old QEMU or passes -vga cirrus.

Regards,

Florian

Great find! Indeed, lspci lists

00:02.0 VGA compatible controller: Cirrus Logic GD 5446

Is this something that could be fixed by including a driver for that

card in the kernel?

On Thu, 27 Jun 2019 08:34:21 +0200

Robert Vollmert <rob@vllmrt.net> wrote:

[..]

Yes, good catch! On my server I find the exact same Cirrus Logic driver

with lspci. Furthermore, when starting locally the QEMU-Instance with

the "-vga cirrus" option, viewing the installer through vinagre shows a

cropped scene (screenshot attached).

Björn

Hello,

Robert Vollmert <rob@vllmrt.net> skribis:

I suppose so.

Mark, WDYT about adding support for Cirrus VGA cards to the kernel?

What would it take to do so?

Thanks,

Ludo’.

Hi,

Ludovic Courtès <ludo@gnu.org> wrote:

I know of two kernel configuration options for Cirrus video cards:

CONFIG_DRM_CIRRUS_QEMU: Cirrus driver for QEMU emulated device

CONFIG_FB_CIRRUS: Cirrus Logic support

CONFIG_DRM_CIRRUS_QEMU is enabled as a module in all of our

configurations except for 5.2-arm-veyron.conf. CONFIG_FB_CIRRUS is

enabled as a module in all of our x86_64 and i686 configurations.

Is there something else I've overlooked?

Thanks,

Mark

Hi Mark,

Mark H Weaver <mhw@netris.org> skribis:

[...]

Oh, I see.

Robert and Björn, could you check if adding the ‘cirrus’ and possibly

the ‘cirrusfb’ module(s) to ‘initrd-modules’ in the image you run at

your VPS solves the issue?

TIA,

Ludo’.

It would need to be added to the installer. Is there a way to add it

via grub command line? Alternatively, is there a way to test this from

a regular guix system console?

(I’m not sure to what extent I’ll be able to do that — my VPS is now

serving “important” things. Note that the bug is reproducible on QEMU

by passing “-vga cirrus”.)

On Sat, 20 Jul 2019 17:17:21 +0200

Robert Vollmert <rob@vllmrt.net> wrote:

Hi Robert,

it is possible to create your own installation-image from sources. If

you are not familar with, check the manual on how to build Guix from

source. Then I did and can confirm locally:

qemu-system-x86_64 -vga cirrus -monitor stdio -m 1024 -smp 1 -enable-kvm -vnc :0 -cdrom /home/bjoern/qemu/installer2/guix-system-install-1.0.1.x86_64-linux.iso

This looks expectedly distorted.

On commit (without any changes):

59f79254bbd2cfe31dd063a6949f94e09308e799

I created the installation image:

[env]$ ./pre-inst-env guix system disk-image --file-system-type=iso9660 gnu/system/install.scm

[..]

/gnu/store/dp9yj0kv20hzwj70b0qkw2yn9vd2h6s4-image.iso

Starting it in QEMU:

qemu-system-x86_64 -vga cirrus -monitor stdio -m 1024 -smp 1 -enable-kvm -vnc :0 -cdrom /gnu/store/dp9yj0kv20hzwj70b0qkw2yn9vd2h6s4-image.iso

This still has the too small view on the installer.

Then I changed the installer code to add the modules:

[env]$ git diff | more

Hello!

Björn Höfling <bjoern.hoefling@bjoernhoefling.de> skribis:

Awesome!

Please let us know when you have feedback on these so we can add just

the module that makes sense.

Thank you!

Ludo’.

On Mon, 22 Jul 2019 12:25:12 +0200

Ludovic Courtès <ludo@gnu.org> wrote:

I tried all three combinations and all work with qemu:

1. (initrd-modules (append (list "cirrus" "cirrusfb")

2. (initrd-modules (append (list "cirrusfb")

3. (initrd-modules (append (list "cirrus")

I tried the version with "cirrus" on my VPS and it worked there too.

When I read the comments in the drivers, it looks like the "cirrus" is

implemented for qemu:

That's the result of my tests. I know too few about kernels/drivers to

really decide what the best would be here.

Ludo or Mark, could one of you go on further from here?

Thanks,

Björn

Hello Björn,

Björn Höfling <bjoern.hoefling@bjoernhoefling.de> skribis:

Cool, thanks for testing.

One easy thing we can do is to arrange so that ‘guix system vm{,-image}’

always include this module in the initrd. I believe that would address

your use case, right?

Patch below.

Thanks,

Ludo’.

merge 36069 60002

quit

close 60002

quit

open 36069

--

3 years later i was also hindered by this (see #60002). in my case it was "fixed" (read: avoided) by my VPS provider specifying a different vga argument for my VM.

maybe this patch should be applied?

'cirrus' was the default before QEMU 2.2 (~2017), and 'std' is the default since QEMU 2.2.

"-vga cirrus - Simple graphics card. Every guest OS has a built-in driver."

--

• attila lendvai

• PGP: 963F 5D5F 45C7 DFCD 0A39

--

“You don't need another human being to make your life complete, but let's be honest. Having your wounds kissed by someone who doesn't see them as disasters in your soul, but cracks to put their love into, is the most calming thing in this world.”

— Emery Allen

merge 60002 60002

quit

I pushed a version of Ludo's suggestion earlier today. And yes, cirrus is what we want here.

Kind regards,

T G-R

Sent on the go. Excuse or enjoy my brevity.