Re: Droid 4 regression in 5.5-rc1, armsoc-soc tree

From: Pavel Machek
Date: Thu Jan 02 2020 - 14:18:13 EST


> * Arnd Bergmann <arnd@xxxxxxxx> [200102 14:48]:
> > On Thu, Jan 2, 2020 at 3:06 PM Pavel Machek <pavel@xxxxxx> wrote:
> >
> > > # good: [ab818f0999dc73af3f966194d087e9f6650f939f] Merge tag
> > > # 'omap-for-v5.5/maintainers-signed' of
> > > # git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into
> > > # arm/soc
> > > git bisect good ab818f0999dc73af3f966194d087e9f6650f939f
> > > # first bad commit: [38206c24ab09b4f4c2a57de5c1af0bb2e69cf5b6] Merge tag
> > > # 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
> > >
> > > ...and am not sure how to interpret the result, or what to do next :(.
> >
> > This means that either the bisection is unreliable (it might be 100%
> > reproducible or you mixed up good/bad once), or that the arm-soc
> > branch was indeed good by itself but had a conflict with some other
> > change that torvalds merged earlier.
> >
> > I would suggest to go back to the list I had extracted in my previous
> > email and revert all the commits that I identify there, on top of
> > linux-5.5-rc4. If some commit is not easily reverted, skip that one
> > at first.
> >
> > Ideally this gets you a working kernel based on -rc4, and then
> > you can bisect that to find which revert fixed it.
>
> Also please check your dtb is up to date. We still have a lot of
> stuff missing from the device tree meaning an old dtb will likely
> be incomplete for many devices.

Aha, so it works ok when using matching kernel + dtb.

Is 5.5 kernel with 5.3 dtb situation worth debugging?

Best regards,
Pavel