Subject: Re: [U-Boot] [PATCH 2/2] net: ping,arp: Fix cache alignment issues Message-ID: 099414db-a264-a3ac-8aae-fb8aa0d969ee@denx.de Content-Type: text/plain; charset=utf-8; format=flowed
On 28.05.2018 08:33, Baruch Siach wrote:
From: Jon Nettleton jon@solid-run.com
Both ping_receive and arp_receive would transmit a received packet back out using its original point. This causes problems with certain network cards that add a custom header to the packet. Specifically the mvneta driver for the Armada series boards has a 2 byte Marvell header that is bypassed and passed along to the system, but that 2 byte offset now causes a misalignment if it is attempted to be sent back out.
Rather than changing the driver to memcpy all the received packets to cache aligned buffers we instead change the two offending network commands to copy the packet into a cache aligned net_tx_packet before sending it back out.
This fixes occasional messages like:
CACHE: Misaligned operation at range [3fc01082, 3fc010c2]
___________________________________________________________________ This is not a good idea. I believe it should be implemented in the driver. Putting it in in the app code leads to confusionas to its purpose. Duncan Hare
714 931 7952