device driver memory leak in 5.1-20030726?

Bosko Milekic bmilekic at
Sun Jul 27 08:49:08 PDT 2003

On Sun, Jul 27, 2003 at 04:43:32PM +0200, Lukas Ertl wrote:
> On Sun, 27 Jul 2003, Mark Blackman wrote:
> > Perhaps it's a USB bug. There seems to be some correspondence between
> > the use of the USB Speedtouch ADSL modem and the out-of-control
> > devbuf allocations.
> I'm too seeing these annoying kmem_malloc panics on recent -current
> kernels. The laptop I'm using is way off of being overloaded at all, the
> only thing I do is going online using a Bluetooth USB dongle. As soon as I
> generate some network traffic, devbuf allocations go up, until at some
> point the machine panics randomly in kmem_malloc.
> I have different core dumps and backtraces available, but they don't seem
> to be of much use in this case. I really suspect the USB stuff to be
> leaking.
> regards,
> le

  There are two problems.

  1) The USB code never frees the stuff it allocates;

  2) The USB code places the stuff it allocates into a couple of lists
  unprotected by any mutexes.  It should at a minimum assert that Giant
  is held coming in, at all times.

> -- 
> Lukas Ertl                             eMail: l.ertl at
> UNIX Systemadministrator               Tel.:  (+43 1) 4277-14073
> Vienna University Computer Center      Fax.:  (+43 1) 4277-9140
> University of Vienna         

Bosko Milekic  *  bmilekic at  *  bmilekic at
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