ubuntu-phone team mailing list archive

[Torsten Sachse <torsten.sachse@xxxxxxxxx>]

On Tue, 16 Jun 2015, Oliver Grawert wrote:

> if you ever made your device writable, installed any debs or changed any
> files that are usually in the readonly space there is no guarantee at
> all that any update will ever work and you are pretty much on your
> own ...

This raises the question about why to include these tools in consumer(!)
builds in the first place, if everything you can do with them is brick
your device. Unless of cource they're needed for some system
functionalities, in which case they are needed in both developer and
consumer builds.

In that case, they could be

a) located in a directory which is not in the default PATH making it
more difficult to access them

b) shadowed by some wrappers that are issuing warnings, such as
"WARNING: using this command is not supported and might very well brick
your phone. Only proceed if you know what you are doing."

c) adjusted so that, for instance, mount is issuing warnings when it is
being used to mount / in rw-mode, forcing the person to accept the risk.
These warnings could include a link to a webpage on the topic.

> the solution is pretty simple, don't tinker with the device if you need
> to rely on it ... the OTAs are binary diffs between two predefined
> readonly images, if you changed the base image of this diff process in
> any way nobody can tell what happens ...

I agree, but ...

> while you *can* make it writable all documentation that talks about it
> definitely has a big fat warning that you are likely ending up in a
> situation where it will break and you have to re-flash from scratch ...

... the main problem, IMHO, is that you never receive a proper warning
message on the phone itself. Since the update from r21 to r22 worked
without problems for me, despite the fact that I modified some bits of
the ro file system, it took me a while to suspect the new update.

It can very well be the case that all documentation about that contains
appropriate wrnings, but the article on stackexchange/stackoverflow (I
always mix up the two) that I found did not contain such a warning at
the time. If you imagine case [1], which is actually almost exactly what
happened to me, I think it's clear this has to be adressed somehow. If
you think otherwise, please let me know.

Cheers,
Torsten

[1]:
- a person used to Ubuntu/Linux Mint and the command line on their
  computer decides to buy a phone sporting Ubuntu Touch
- this person finds (put the name of any amazing command line programme
  here) to be unavaiable on the phone and tries what he or she is used
  to, i.e., to run apt-get
- a warning about the read-only nature of / is being issued and an
  article somewhere on the internet (not necessarily an ubuntu
  forum/website) tells to mount / -o remount,rw
- apt-get works as expected but the next update breaks the phone
- the person is upset with the phone