installer crashes after importing my launchpad SSH key

[Patricia Domingues]

I was trying to install noble (.ISO) on PowerVM nodes - Power9 LPAR and Power10 LPAR
and the installer crashes after I import mey ssh key from launchpad:
tried with todays image `noble-live-server-ppc64el.iso 2024-03-01 09:05`

subiquity version `subiquity 22.02.2+git2049.f759d193 5537 latest/stable/`

 File "/snap/subiquity/5537/usr/lib/python3/dist-packages/urwid/canvas.py", line 1315, in apply_text_layout
     return TextCanvas(t, a, c, maxcol=maxcol)
   File "/snap/subiquity/5537/usr/lib/python3/dist-packages/urwid/canvas.py", line 358, in __init__
     raise CanvasError("Canvas text is wider than the maxcol specified \n%r\n%r\n%r"%(maxcol,widths,text))
 urwid.canvas.CanvasError: Canvas text is wider than the maxcol specified

2024-03-01 15:04:02,997 DEBUG subiquity/SSH/ssh_import_id:105 start: lp:patriciasd
 2024-03-01 15:04:04,035 DEBUG subiquity/SSH/ssh_import_id:110 finish: lp:patriciasd SUCCESS
 2024-03-01 15:04:10,486 DEBUG subiquity.common.errorreport:398 generating crash report
 2024-03-01 15:04:10,503 INFO subiquity.common.errorreport:424 saving crash report 'Installer UI crashed with CanvasError' to /var/crash/1709305450.487099409.ui.crash
 2024-03-01 15:04:10,503 INFO subiquity/ErrorReporter/1709305450.487099409.ui/add_info:105 start:
InstallerClientLogInfo:
 2024-03-01 15:02:40,514 INFO subiquity:130 Starting Subiquity TUI revision 5537 of snap /snap/subiquity/5537
 2024-03-01 15:02:40,515 INFO subiquity:131 Arguments passed: ['/snap/subiquity/5537/usr/bin/subiquity', '--serial']
 2024-03-01 15:02:41,810 INFO subiquity/Serial:105 start: starting UI

[Patricia Domingues (patriciasd)]

If I skip adding my launchpad key I can install noble on both systems and boot successfully :
`:~$ cat /var/log/installer/media-info
Ubuntu-Server 24.04 LTS "Noble Numbat" - Daily ppc64el (20240301)patricia@noble:~$`

[Dan Bungert (dbungert)]

Hi Patricia, thanks for the report.

I made a few attempts on amd64 here, but I doubt it's architecture specific. I wasn't able to reproduce the issue.

Can you give me more information about the terminal setup?

[Olivier Gayot (ogayot)]

Hello,

I looks related to how we draw the UI in serial mode:

```
make dryrun-serial
```

And choose "Continue in basic mode" when prompted.

Olivier

[Patricia Domingues (patriciasd)]

I was retrying that with another key, from `fheimes` and I don't hit the crash. If I try to add mine `patriciasd` I still see the failure, doesn't matter if running on rich or basic mode.

[Sergio Durigan Junior (sergiodj)]

I can confirm this problem. I'm investigating the same underlying problem as Patrícia, so it's no surprise that I triggered this subiquity error under the same circumstances.

[Olivier Gayot (ogayot)]

It looks like we're hitting an urwid issue when trying to render the ellipsis "…" character on serial.

https://github.com/urwid/urwid/issues/812

which has a fix which is already part of noble.

[Frank Heimes (fheimes)]

Hi Olivier, thanks for the investigations.

Well, we recently had the 22.04.4 release where we did quite some testing upfront - using the same systems with the same accounts, but haven't hit this kind of issue (and btw. same for mantic).

You're writing that the fix is already in noble? Was it recently added?
We will soon start another round of noble testing (now that we are in 'Testing week') and will ensure that we are on the very latest image and see if things have changed ...

[Olivier Gayot (ogayot)]

https://github.com/canonical/subiquity/pull/1924

[Olivier Gayot (ogayot)]

Hello Frank,

Yes, the SSH UI was reworked for noble, and this is what introduced the regression, so this is why the bug did not occur on 22.04.4 (UI rework is not part of 22.04.4).

To be clear, the root cause of the crash is in urwid (the library we use for drawing screens in subiquity). The version of urwid in noble (i.e. 2.6.4-1) has a fix [1] (it's from 2 weeks ago). That said, in the installer images that we ship, we use packages from core22 (so urwid 2.1.2-2build1).

I've opened a PR in subiquity to avoid using the broken feature of urwid ; until we switch to core24.

Thanks,
Olivier

[1] https://github.com/urwid/urwid/pull/813/commits/7c955f93d77723508a78d044c7552c5730244187

[Patricia Domingues (patriciasd)]

updating subiquity to Version `22.02.2+git2100.4fba6aa7` - I'm now able to import my launchpad' SSH key.

[Dan Bungert (dbungert)]

Thanks Patricia. I'm marking the Subiquity part of this Fix Released for a noble-specific issue.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.