Re: Is this a preempt issue in drivers/input/evdev.c

From: Jens Axboe
Date: Sun May 13 2007 - 14:13:36 EST


On Sat, May 12 2007, Dmitry Torokhov wrote:
> Hi,
>
> On Friday 11 May 2007 23:18, Yin,Fengwei wrote:
> >
> > So if the evdev_release() is preempted at the point marked by another
> > process which will open the evdev, which will make operation sequence
> > like:
> >
> > --evdev->open in evdev_release()
> > -----> preempted
> > evdev->open++ and input_open_devie()
> > <----- reschedule
> > input_close_device()
> >
> > Should we introduce a mutex here? Or do I miss something? Thanks.
> >
>
> Locking is completely absent in evdev. There was a patch introducing
> locking in recent -mm's but it got dropped. I need to refresh it.

How did stuff like that ever get merged, btw? I still have a completely
trivially oopsable rmmod psmouse problem, I hope it'll get fixed for
2.6.22.

--
Jens Axboe

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