ipq40xx: essedma: Disable TCP segmentation offload for IPv6
authorSven Eckelmann <sven@narfation.org>
Tue, 9 Jun 2020 13:35:04 +0000 (15:35 +0200)
committerChristian Lamparter <chunkeey@gmail.com>
Sat, 13 Jun 2020 12:38:03 +0000 (14:38 +0200)
commit678569505623e50bbbbc344c7e820fb315b79ede
treee82dfd2ba6e92cdf69414210c7dfedc160dfdf6b
parent5549b843885fb984bf1ec8c771c4598140eb3b6e
ipq40xx: essedma: Disable TCP segmentation offload for IPv6

It was noticed that the the whole MAC can hang when transferring data from
one ar40xx port (WAN ports) to the CPU and from the CPU back to another
ar40xx port (LAN ports). The CPU was doing only NATing in that process.

Usually, the problem first starts with a simple data corruption:

  $ wget https://cdimage.debian.org/debian-cd/current/amd64/iso-cd/debian-10.4.0-amd64-netinst.iso -O /dev/null
  ...
  Connecting to saimei.ftp.acc.umu.se (saimei.ftp.acc.umu.se)|2001:6b0:19::138|:443... connected.
  ...
  Read  error at byte 48807936/352321536 (Decryption has failed.). Retrying.

But after a short while, the whole MAC will stop to react. No traffic can
be transported anymore from the CPU port from/to the AR40xx PHY/switch and
the MAC has to be resetted.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: John Crispin <john@phrozen.org>
target/linux/ipq40xx/files-5.4/drivers/net/ethernet/qualcomm/essedma/edma_axi.c