From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Date: Fri, 12 May 2017 06:20:04 +0000 Subject: Re: setting brightness as privileged operation? Message-Id: <20170512062003.GB6803@dhcp22.suse.cz> List-Id: References: <20170105092307.GD21618@dhcp22.suse.cz> <20170511210755.GA1360@xo-6d-61-c0.localdomain> In-Reply-To: <20170511210755.GA1360@xo-6d-61-c0.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Pavel Machek Cc: Jingoo Han , Lee Jones , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org On Thu 11-05-17 23:07:55, Pavel Machek wrote: > On Thu 2017-01-05 10:23:07, Michal Hocko wrote: > > Hi, > > I have just learned that my Xfce Power Manager cannot manipulate > > brightness because I do not have policykit installed on my computer. > > There is a reason for that (yeah it depends on systemd which I prefer > > not have). > > > > While this is clearly a problem of the Xfce applet I am wondering why > > setting the brightness has to be a privileged operation at all. Is there > > any strong reason for it or just a general policy that we do not give > > world writable files into sysfs? > > Well, if you have another user logged in using ssh, and changing _your_ > brightness, that will be somehow annoying, right? I am pretty sure that such a user can do much larger harm than playing with brigtness of my LCD. Anyway I went with my own rc.local hack. -- Michal Hocko SUSE Labs