Re: No input (was: Black screen / X issue fixed)

[Matthias Klumpp]

2017-08-19 5:06 GMT+02:00 Cyril Brulebois :
> Cyril Brulebois  (2017-08-13):
>> This is fun: the bug is “fixed” in that the language selection screen
>> pops up properly, but it's not actually possible to get any input (incl.
>> VT switching) into the installer. I'll look into this once I'm back from
>> DebConf.
>
> And here's the culprit/bug report:
>   https://bugs.debian.org/872598

Thank you for discovering this! Let's hope this can be addressed soon :-)
I'll look into udev later (when I am not falling asleep any minute)

Cheers,
Matthias

-- 
I welcome VSRE emails. See http://vsre.info/

No input (was: Black screen / X issue fixed)

[Cyril Brulebois]

Cyril Brulebois  (2017-08-13):
> This is fun: the bug is “fixed” in that the language selection screen
> pops up properly, but it's not actually possible to get any input (incl.
> VT switching) into the installer. I'll look into this once I'm back from
> DebConf.

And here's the culprit/bug report:
  https://bugs.debian.org/872598


KiBi.


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Re: Black screen / X issue fixed

[Cyril Brulebois]

Philip Hands  (2017-08-15):
> Oh, and the "obviously" wasn't meant to be something like a complaint,
> just saying that it was the thing that was causing some of the installs
> to grind to a halt -- so nothing to say sorry for.
> 
> Sorry if what I said sounded like I was grumpy about it -- that was not
> even slightly the case. :-)

Oh, no worries, was just mentioning why I didn't connect the dots
properly when the topic was brought up.

Thanks for the instructions in the other mail, will look when I have a
chance, probably in a few days.


KiBi.


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Re: Black screen / X issue fixed

[Philip Hands]

Cyril Brulebois  writes:

> Hi,
>
> Philip Hands  (2017-08-14):
>> Yes that's the behaviour I was commenting on in IRC, and which was
>> obviously being spotted by the jenkins/cucumber setup.
>
> Sorry, based on earlier comments over the previous days/weeks, I went
> for a “X is broken” shortcut and might not have actually got your exact
> point.

Oh, and the "obviously" wasn't meant to be something like a complaint,
just saying that it was the thing that was causing some of the installs
to grind to a halt -- so nothing to say sorry for.

Sorry if what I said sounded like I was grumpy about it -- that was not
even slightly the case. :-)

Cheers, Phil.
-- 
|)|  Philip Hands  [+44 (0)20 8530 9560]  HANDS.COM Ltd.
|-|  http://www.hands.com/http://ftp.uk.debian.org/
|(|  Hugo-Klemm-Strasse 34,   21075 Hamburg,GERMANY


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Re: Black screen / X issue fixed

[Philip Hands]

Cyril Brulebois  writes:

> Hi,
>
> Philip Hands  (2017-08-14):
>> Yes that's the behaviour I was commenting on in IRC, and which was
>> obviously being spotted by the jenkins/cucumber setup.
>
> Sorry, based on earlier comments over the previous days/weeks, I went
> for a “X is broken” shortcut and might not have actually got your exact
> point.
>
>> BTW It is possible to run get something like shell access to the
>> running d-i via its ttyS0 (by putting rather a lot of stuff on the
>> kernel boot command line), so if that would help I can run tests for
>> you and/or explain the proceedure.
>
> If you would have a little time to explain this, that would be immensely
> useful. Feel free to just sum it up quickly in an email, I might write
> some docs about it afterwards.

Well, it's a bit horrible, but as long as you don't need to type the
kernel command line by hand it's OK.

The code that does the trick is here:

  
https://anonscm.debian.org/cgit/qa/jenkins.debian.net.git/tree/cucumber/features/step_definitions/common_steps.rb#n217

which you can see the result of at about 27 seconds into this:

  
https://jenkins.debian.net/view/lvc/job/lvc_debian-testing-daily/1341/artifact/results/00%3A01%3A57_Install_Debian,_and_boot_to_a_login_prompt,_Examples___1_.mpg

What that does is start a while loop that reads from /dev/ttyS0, and
runs the commands that you type, returning the STDOUT, STDERR, and
result code, separated by various control characters which you probably
don't care about.

If you do that, then you can use nc (or whatever) to connect to the TCP
port which is defined for the KVM's ttyS0, and type commands, and get
their output, followed by a result code.  It's almost like having a shell
prompt, other than the slightly odd ordering of STDERR and the result.

It would probably be better to have a udeb that contains a thing for
running the listener, like the debugging thing that is available in
tails -- theirs returns results in json, and lets one run as users other
than root, and can drop thing into the background, but we don't really
need all that in d-i.

Cheers, Phil.
-- 
|)|  Philip Hands  [+44 (0)20 8530 9560]  HANDS.COM Ltd.
|-|  http://www.hands.com/http://ftp.uk.debian.org/
|(|  Hugo-Klemm-Strasse 34,   21075 Hamburg,GERMANY


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Re: Black screen / X issue fixed

[Cyril Brulebois]

Hi,

Philip Hands  (2017-08-14):
> Yes that's the behaviour I was commenting on in IRC, and which was
> obviously being spotted by the jenkins/cucumber setup.

Sorry, based on earlier comments over the previous days/weeks, I went
for a “X is broken” shortcut and might not have actually got your exact
point.

> BTW It is possible to run get something like shell access to the
> running d-i via its ttyS0 (by putting rather a lot of stuff on the
> kernel boot command line), so if that would help I can run tests for
> you and/or explain the proceedure.

If you would have a little time to explain this, that would be immensely
useful. Feel free to just sum it up quickly in an email, I might write
some docs about it afterwards.

Thanks!


KiBi.


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Re: Black screen / X issue fixed

[Philip Hands]

Cyril Brulebois  writes:

> Cyril Brulebois  (2017-08-08):
>> So I've been meaning to debug the black screen in graphical installer
>> for quite a while, but I've been busy with preparing for my talk, then
>> discussing busybox with new recruits.
>> 
>> I've finally managed to bisect that down to the following dinstalls:
>>   2017-06-20 22:37:45 (last OK)
>>   2017-06-21 03:38:47 (first KO)
>> 
>> and out of the 6 packages, I've isolated the culprit:
>>   libexpat1-udeb_2.2.1-1_amd64.udeb
>> 
>> Right afterwards I've discovered that an installer built against
>> unstable… just works again. I'm suspecting the new expat upstream
>> version might have been the fix we needed:
>>   https://tracker.debian.org/news/860347
>> 
>> But I doubt it makes much sense to also isolate what/when the exact
>> fix happened. I thought I would just share the “when did it break?”
>> part.
>
> This is fun: the bug is “fixed” in that the language selection screen
> pops up properly, but it's not actually possible to get any input (incl.
> VT switching) into the installer. I'll look into this once I'm back from
> DebConf.

Yes that's the behaviour I was commenting on in IRC, and which was
obviously being spotted by the jenkins/cucumber setup.

BTW It is possible to run get something like shell access to the running
d-i via its ttyS0 (by putting rather a lot of stuff on the kernel boot
command line), so if that would help I can run tests for you and/or
explain the proceedure.

Cheers, Phil.
-- 
|)|  Philip Hands  [+44 (0)20 8530 9560]  HANDS.COM Ltd.
|-|  http://www.hands.com/http://ftp.uk.debian.org/
|(|  Hugo-Klemm-Strasse 34,   21075 Hamburg,GERMANY


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Re: Black screen / X issue fixed

[Cyril Brulebois]

Cyril Brulebois  (2017-08-08):
> So I've been meaning to debug the black screen in graphical installer
> for quite a while, but I've been busy with preparing for my talk, then
> discussing busybox with new recruits.
> 
> I've finally managed to bisect that down to the following dinstalls:
>   2017-06-20 22:37:45 (last OK)
>   2017-06-21 03:38:47 (first KO)
> 
> and out of the 6 packages, I've isolated the culprit:
>   libexpat1-udeb_2.2.1-1_amd64.udeb
> 
> Right afterwards I've discovered that an installer built against
> unstable… just works again. I'm suspecting the new expat upstream
> version might have been the fix we needed:
>   https://tracker.debian.org/news/860347
> 
> But I doubt it makes much sense to also isolate what/when the exact
> fix happened. I thought I would just share the “when did it break?”
> part.

This is fun: the bug is “fixed” in that the language selection screen
pops up properly, but it's not actually possible to get any input (incl.
VT switching) into the installer. I'll look into this once I'm back from
DebConf.


KiBi.


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Black screen / X issue fixed

[Cyril Brulebois]

Hi,

So I've been meaning to debug the black screen in graphical installer
for quite a while, but I've been busy with preparing for my talk, then
discussing busybox with new recruits.

I've finally managed to bisect that down to the following dinstalls:
  2017-06-20 22:37:45 (last OK)
  2017-06-21 03:38:47 (first KO)

and out of the 6 packages, I've isolated the culprit:
  libexpat1-udeb_2.2.1-1_amd64.udeb

Right afterwards I've discovered that an installer built against
unstable… just works again. I'm suspecting the new expat upstream
version might have been the fix we needed:
  https://tracker.debian.org/news/860347

But I doubt it makes much sense to also isolate what/when the exact
fix happened. I thought I would just share the “when did it break?”
part.


KiBi.


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