Messages in this thread Patch in this message | | | From | Dmitry Torokhov <> | Subject | Re: [PATCH] atkbd: cleanup only once | Date | Thu, 28 Jun 2007 01:18:35 -0400 |
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On Wednesday 27 June 2007 01:02, dave young wrote: > 2007/6/27, Dmitry Torokhov <dtor@insightbb.com>: > > On Wednesday 27 June 2007 00:28, Greg KH wrote: > > > On Wed, Jun 27, 2007 at 12:34:09AM -0400, Dmitry Torokhov wrote: > > > > Hi Dave, > > > > > > > > On Wednesday 27 June 2007 06:59, Dave Young wrote: > > > > > Hi, > > > > > > > > > > If you press ctrl+alt+del several times as kernel booting (before user level bootin), the kernel will oops. I found the ps2_command is called more than once, then the ps2dev->serio maybe NULL pointer. > > > > > > > > > > 2.6.22-rc5 and 2.6.22-rc6 have same result. > > > > > > > > > > Signed-off-by: Dave Young <hidave.darkstar@gmail.com> > > > > > --- > > > > > diff -upr linux/drivers/input/keyboard/atkbd.c linux.new/drivers/input/keyboard/atkbd.c > > > > > --- linux/drivers/input/keyboard/atkbd.c 2007-06-27 10:38:37.000000000 +0000 > > > > > +++ linux.new/drivers/input/keyboard/atkbd.c 2007-06-27 10:37:39.000000000 +0000 > > > > > @@ -795,6 +795,11 @@ static int atkbd_activate(struct atkbd * > > > > > > > > > > static void atkbd_cleanup(struct serio *serio) > > > > > { > > > > > + static int flag; > > > > > + > > > > > + if(flag) > > > > > + return; > > > > > + flag = 1; > > > > > > > > Unfortunately this will prevent atkbd from resetting keyboard on 2nd > > > > suspend attempt. It will also not work if you have an active MUX and > > > > have a couple of keyboards connected. > > > > > > > > Greg, now that you removed rwsem from subsystem (and subsystem itself > > > > for that matter) there is nothing as far as I can see that stops > > > > several threads from running device_shutdown() simultaneously. I also > > > > do not see what would isolate device probing and shutting them down > > > > at the same time. Am I missing something? > > > > > > There was never anything stopping that from happening before. No driver > > > core code was using that rwsem, so it wasn't protecting anything, > > > despite people trying to use it as if it was :) > > > > > > > It did protect device_shutdown() from itself, didn't it? > > > > -- > > Dmitry > > > how about check ps2dev->serio in ps2_command before use it?
I don't think we ever set it to NULL. Does the patch below help any?
-- Dmitry
Signed-off-by: Dmitry Torokhov <dtor@mail.ru> ---
drivers/input/serio/serio.c | 2 ++ 1 files changed, 2 insertions(+)
Index: work/drivers/input/serio/serio.c =================================================================== --- work.orig/drivers/input/serio/serio.c +++ work/drivers/input/serio/serio.c @@ -769,8 +769,10 @@ static int serio_driver_remove(struct de static void serio_cleanup(struct serio *serio) { + mutex_lock(&serio->drv_mutex); if (serio->drv && serio->drv->cleanup) serio->drv->cleanup(serio); + mutex_unlock(&serio->drv_mutex); } static void serio_shutdown(struct device *dev) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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