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Date: Sat, 11 Jul 2026 09:43:28 +0200
From: Greg KH <gregkh@linuxfoundation.org>
To: Papool Chaudhari <Papool@chaudharilaw.com>
Cc: regressions@lists.linux.dev
Subject: Re: [REGRESSION] 2017 =?utf-8?Q?Pixelbook_?=
 =?utf-8?Q?backlight_control_doesn=E2=80=99t?= work with 7.1 kernel
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On Sat, Jul 11, 2026 at 01:11:06AM -0600, Papool Chaudhari wrote:
> I tried reverting commit b3793af3277f65d256d67f9949e760b434ff66dd on
> top of v7.1, but the resulting kernel completely hangs at 'Loading
> initial ramdisk'. Even when adding 'nomodeset' via GRUB, the crash
> happens so early that no kernel text or console output is ever
> printed. It appears this Intel THC merge cannot be cleanly isolated or
> reverted on v7.1 without causing an immediate early boot failure on
> this hardware.

A merge point is usually not a good place to revert, as that can be
"odd".  I also don't really see a diff at this point in time, so can you
try both sides of the merge to see if they both work, or not?

thanks,

greg k-h