Re: Linux 7.1-rc1

[Linus Torvalds]

On Tue, 28 Apr 2026 at 11:11, Luna Jernberg <droidbittin@xxxxxxxxx> wrote:
>
> have checked dmesg now, seems to be a module that's not loading as it should

Hmm. Interesting, but I wouldn't expect that LPSS driver to matter.  I
think it's mainly used for some random SoC boards, not by the display
backlight code.

And in the full dmesg I then see

  intel-lpss 0000:00:15.2: enabling device (0000 -> 0002)
  intel-lpss 0000:00:15.3: enabling device (0000 -> 0002)

so I think it all should work regardless.

Of course, maybe it does mess up i2c or something, which then messes
up EDID or whatever, but I would expect the backlight to most likely
be controlled by aome ACPI thing.

So that module failure sounds to me like it should be unrelated - and
might happen even on a working setup?

I'm adding Rafael to the cc anyway, because he'd likely know about
both the OpRegion conflict thing, but also maybe if something has
changed in the ACPI backlight situation that might be the cause of
your backlight issues...

(Rafael, see

  https://lore.kernel.org/all/CADo9pHg8c=rouBQAd0o0TzK4iZc88dUAhSfV7q2T3GCf2qjuiQ@xxxxxxxxxxxxxx/

for dmesg etc information)

If you can try to bisect the failure - even if just doing a handful of
boot tests - that would likely narrow it down at least a bit.

If you haven't done bisections before, they are actually pretty
simple. Just time-consuming during the merge window because it ends up
doing a full kernel build. Just do

    git bisect start
    git bisect good v7.0  # assuming 7.0 worked fine
    git bisect bad v7.1-rc1

and git will just do the rest and tell you to try various versions in
between it progresses.

(See Documentation/admin-guide/bug-bisect.rst for much more in-depth
information)

             Linus