Re: 6.0.0-RC kernels trigger Firefox snap bug with 6.0.0-rc3 through 6.0.0-rc7

[Mirsad Todorovac]

Hi everybody,

On 10/13/22 15:24, Mirsad Goran Todorovac wrote:

> Thank you for the instruction for how to shorten the bisection time. 
> My fastest build was almost 2 hours.
>
> This bug did appear with the mainline Ubuntu's and ElRepo's 6.0.0 
> kernels, however not with the
> /usr/bin/firefox build, but only that using snapd, squashfs and 
> /snap/bin/firefox ...
>
> The Firefox 91.x esr was unaffected, indeed, in a couple of days of 
> testing its work (on AL).
>
> However, please not that this bug is no deterministic, and that it can 
> take from a couple of hours
> to an overnight work to manifest.
>
> The "make localmodconfig" feature will probably help reducing the 
> build time, but I am also doing
> my day job stuff which by the Murphy's law surged right now ...
>
> You second request, to reproduce with Firefox from the dev site, is as 
> you will understand impossible
> to meet: the bug occurred only with Firefox 104.x and 105.0.1, 
> 105.0.2, 105.0.3 in Ubuntu snap
> release (and the snap release guest installed at AlmaLinux, the CentOS 
> fork).
>
> I was able to confirm that AppArmor doesn't affect behaviour once the 
> Firefox misbehaves.
> After starting to crash tabs and refusing to connect to the Internet 
> from inside Yahoo mail (Chrome
> simultaneously connected), then it complained about libmozsandbox.so 
> version and Verneed record.
>
> -Mirsad
>
> On 12.10.2022. 9:46, Bagas Sanjaya wrote:
> > Hi Mirsad,
> >
> > The bug doesn't appear on 6.0 mainline release. However, in my case,
> > Firefox is downloaded and installed from official Mozilla binary [1].
> >
> > Also, many developers here want to see bisection result. In order to
> > shorten kernel build time (and thus time needed for bisection),
> > you can strip out unneeded modules in your kernel configuration with
> > "make localmodconfig". Ensure that all devices on your computer is
> > plugged in before running that. And as other people pointed, base
> > your localmodconfig from last working kernel.
> >
> > In any case, please reproduce with Firefox from [1].
> >
> > Thanks.
> >
> > [1]: https://www.mozilla.org/en-US/firefox/
I tried the "make localmodconfig" and provided the default answers 
([ENTER]) to all questions
the script asked as advised here: 
https://www.stolaf.edu/people/rab/os/linux-compile.html .

However, though it built much faster, the stripped version did not 
trigger the bug.

I am now trying to reproduce the bug with v6.0-rc[123] with 
config-{051913,060000}.
This brings a lot of combinations, and though I am a newbie, I noticed 
that build scripts
start with "make clean" for both deb-pkg and rpm-pkg.

Is there a way to rebuild only the stuff that changed between the versions?

Thank you.

--
Mirsad Goran Todorovac
Sistem inženjer
Grafički fakultet | Akademija likovnih umjetnosti
Sveučilište u Zagrebu
--
System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb, Republic of Croatia