Subject: Re: [ANN] removal of certain net drivers coming soon: eepro100, xircom_tulip_cb, iph5526

From: Russell King <[email-masked]>
Date: Fri, 28 Jan 2005 00:14:30 +0000

On Thu, Jan 27, 2005 at 03:31:14PM -0800, David S. Miller wrote:
> Therefore the only missing sync would be of the new RX descriptor
> when linking things in like that, ie. at the end of e100_rx_alloc_skb()
> if rx->prev->skb is non-NULL.

And that is inherently unsafe, since the chip may be modifying the RFD
while the CPU is accessing it.  Adding extra sync calls does not fix
it because as far as I can see, there's nothing to tell the chip "don't
write to this RFD because any changes the CPU is making right now will
overwrite the chips own changes."

The fact of the matter is that eepro100.c works on ARM, e100.c doesn't.
There's a message from me back on 30th June 2004 at about 10:30 BST on
this very list which generated almost no interest from anyone...

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core