lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Mon, 14 Jul 2014 22:45:07 +0200
From:	Bjørn Mork <>
To:	Linus Torvalds <>
Cc:	Hans de Goede <>,
	Linux Kernel Mailing List <>,
	Linux ACPI <>,
	"Rafael J. Wysocki" <>
Subject: Re: [BISECTED 3.16-rc REGREGRESSION] backlight control stopped working

Linus Torvalds <> writes:
> On Mon, Jul 14, 2014 at 9:24 AM, Linus Torvalds
> <> wrote:
>> Bjørn, what's your setup? Is this perhaps solvable some other way?

Just to answer that: I don't use any particular desktop environment.  I
have acpid running to take care of the most basic power management
stuff.  My X session is simply WindowMaker (sic) running directly from
lightdm.  No session management or fancy policy daemons. So I don't have
any daemon which would react on the brightness key codes.

Now, it's not that I would mind adding a daemon to handle stuff like
brightness control. I reported this as a bug because I was a bit
surprised by the existing behaviour breaking like that, and I thought
that other users might be as surprised as me.  Some maybe even without
the ability to track down the change and the setting that would restore
the old behaviour.

> For example, I wonder if we could fix the "dual brightness change"
> problem automatically by making a new option for
> 'brightness_switch_enabled'.
> Currently, there are two cases:
>  - enabled: do the actual brightness change _and_ send the input
> report keycode for a brightness change
>  - disabled: just send the keycode, excpecting the desktop software to
> handle it.
> and maybe we could have a new case (and make *that* the default):
>  - delayed: send the keycode, and set up a delayed timer (say, one
> tenth of a second) to do the actual brightness change. And if a
> brightness change from user mode comes in during that delay, we cancel
> the kernel-induced pending change.

That sounds like a good solution to me FWIW.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists