Re: 2.5.70: pcmcia oops (a real one! honest!)

[Greg KH <greg@kroah.com>]

On Mon, Jun 02, 2003 at 02:05:37PM -0700, Greg KH wrote:
> On Sun, Jun 01, 2003 at 01:41:42AM +1000, CaT wrote:
> > On Thu, May 29, 2003 at 02:21:39PM -0700, Greg KH wrote:
> > > On Thu, May 29, 2003 at 09:02:09AM +0100, Russell King wrote:
> > > > On Wed, May 28, 2003 at 02:26:10PM +1000, CaT wrote:
> > > > > removed my xircom pcmcia realport card and put in another. End result was
> > > > > total loss of ps2 keyboard functionality (everything else, inc the ps2 mouse
> > > > > still works). I then removed the xircom card. The following was in dmesg:
> > > > 
> > > > I'm assuming that this is something Gregkh needs to look into and not
> > > > myself; my guess is that it's related to the pci device accounting stuff.
> > > > 
> > > > Greg?
> > > 
> > > Yeah, it could be.  Cat, can you revert the following patch from your
> > > tree and let me know if it fixes your problem or not?
> > 
> > The kernel no longer crashes on remove and I can reinsert and it
> > recognises the card without hassle. I do get no messages on eject though
> > (about devices being deregistered, etc) but I get msgs on insert (about
> > them getting regstered etc). One time I didn't get the card recognised
> > at all on insert... dunno if that was myfault or not but on eject and
> > reinsert all was fine.
> 
> Ok, I've duplicated this here with a PCI card containing a bridge on a
> pci hotplug system, so I'll work on tracking this down...

Ah, stupid bug in the driver class code was causing this.  Can you try
this patch out against a clean 2.5.70 tree?  It fixes the problem for
me, and I want to make sure it fixes it for you too.

thanks,

greg k-h

#Driver Class: don't call put_device() when we never called get_device()
#
#This fixes a oops when unplugging pci network devices.
#

diff -Nru a/drivers/base/class.c b/drivers/base/class.c
--- a/drivers/base/class.c	Tue Jun  3 12:24:05 2003
+++ b/drivers/base/class.c	Tue Jun  3 12:24:05 2003
@@ -311,11 +311,8 @@
 		up_write(&parent->subsys.rwsem);
 	}
 
-	if (class_dev->dev) {
-		class_device_dev_unlink(class_dev);
-		class_device_driver_unlink(class_dev);
-		put_device(class_dev->dev);
-	}
+	class_device_dev_unlink(class_dev);
+	class_device_driver_unlink(class_dev);
 	
 	kobject_del(&class_dev->kobj);