linux-kernel - Thunderbolt, Apple Monitor & MBA, and excess kworker load

lists.openwall.net		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-next>] [day] [month] [year] [list]

Message-ID: <20120620154842.GA5788@air.dominikbrodowski.net>
Date:	Wed, 20 Jun 2012 17:48:42 +0200
From:	Dominik Brodowski <linux@...inikbrodowski.net>
To:	daniel.vetter@...ll.ch, dri-devel@...ts.freedesktop.org,
	gregkh@...uxfoundation.org
Cc:	linux-kernel@...r.kernel.org
Subject: Thunderbolt, Apple Monitor & MBA, and excess kworker load

Hi,

At work, I wish to attach a 27" Apple Display using thunderbolt to my Mac
Book Air 4,2 13". Using OS X, it works fine, but as I prefer using Linux, I
tested out Ubuntu's stock kernel and (among other) 3.5.0-rc3+ as of f40759e.
Hotplug doesn't work (known issue), but also with coldplug the display
reacts _very_ slow, way too slow for real use: The screen updates only every
half second or so. Is this a known bug? Might something go afoul with
kworker -- they need about 75% of the CPU with the large display attached,
and less than 1% _without_ the large display.

Any hints are most welcome, also on where I may dig further to determine the
root causes...

Thanks & best,

	Dominik
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/