On Fri, Aug 08, 2008 at 12:49:49PM +0200, Peter Zijlstra wrote: > On Thu, 2008-07-31 at 23:04 -0400, Dmitry Torokhov wrote: > > On Thu, Jul 31, 2008 at 02:57:39PM -0700, Andrew Morton wrote: > > > > > > (cc linux-input) > > > > > > On Thu, 31 Jul 2008 11:41:25 +0200 > > > "Zdenek Kabelac" <zdenek.kabelac@xxxxxxxxx> wrote: > > > > > > > Hi > > > > > > > > During mouse unplugging from psaux connector from the laptops' docking > > > > station I've got attached INFO trace. > > > > (laptops still has synaptics device) > > > > > > > > Dell? > > > > > > Also for unknown reason to me psaux mouse & synaptic device do not > > > > work somehow together - is it hw limitation > > > > of /dev/input/mice interface? > > > > (USB mouse and synaptics do work quite well together) > > > > > > > > [ INFO: possible recursive locking detected ] > > > > 2.6.27-rc1 #48 > > > > > > (it's 2.6.27-rc1) > > > > > > > Peter, here is the trace we talked about long time ago. For some reason > > lockdep annotation only works once. If reconnect is forced or psmouse > > module is reloaded lockdep starts complaining about passthrough port. > > Bit puzzling - and I don't have any ps2 hardware around to test with > (nor do I normally use modules - but that is fixable of course). > > Does Rabin's patch help? > > http://lkml.org/lkml/2008/8/7/329 > I doubt it resolves problem fully because it only takes care of module unload. I can easily trip lockdep by reconnecting the device. Just to give some more details about the problem: - synaptics touchpads have a pass-through port that allows to connect either external mouse or maybe a trackpoint device. Both devices are represented by 'serio' structures and are handled by the same driver (psmouse). - as far as I know we have proper locking there and lockdep annotatinos were added to lockdep to reflect the nesting of the serio ports. - if child port (pass-through port) is destroyed and recreated (due to module unload, or because user requested reconnect through sysfs or system-initiated reconnect) lockdep starts complaining although the new child port should still have the same "depth" as the old one. Thanks! -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
