From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Henningsson Subject: Re: [PATCH 0/2] add sysfs for acpi interfaces of thinkpad hardware mute Date: Wed, 14 Aug 2013 21:53:03 +0200 Message-ID: <520BE01F.9090402@canonical.com> References: <1376458802-11923-1-git-send-email-alex.hung@canonical.com> <1376458937.30031.1.camel@x230> <1376459647.30031.2.camel@x230> <1376460872.30031.4.camel@x230> <1376463610.30031.6.camel@x230> <520B3511.7020604@canonical.com> <1376466691.30031.14.camel@x230> <520B4D71.6070109@canonical.com> <1376492217.28002.1.camel@x230.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1376492217.28002.1.camel@x230.lan> Sender: platform-driver-x86-owner@vger.kernel.org To: Matthew Garrett Cc: Alex Hung , Tim Chen , "ibm-acpi@hmh.eng.br" , "ibm-acpi-devel@lists.sourceforge.net" , "platform-driver-x86@vger.kernel.org" , "alsa-devel@alsa-project.org" , YK List-Id: alsa-devel@alsa-project.org On 08/14/2013 04:57 PM, Matthew Garrett wrote: > On Wed, 2013-08-14 at 11:27 +0200, David Henningsson wrote: > >> The privacy issue is interesting, but I don't see a practical way of >> implementing things that would protect us against compromised userspaces. > > That's pretty easy - just tie the LED control to the HDA device in-kernel. > Well, my point was that the compromised userspace could still record from other possibly connected microphones (such as USB or bluetooth headsets). But I guess one compromise could be to refuse userspace turn the mic mute LED on, if the internal mic is unmuted. Userspace would still be able to turn the mic mute LED off, to indicate that recording can happen from other sources. It will be slightly more complex for userspace though. -- David Henningsson, Canonical Ltd. https://launchpad.net/~diwic