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authorFlorian Fainelli <f.fainelli@gmail.com>2016-09-24 12:58:30 -0700
committerDavid S. Miller <davem@davemloft.net>2016-09-27 07:41:12 -0400
commitbf1a85a8381a0f749aa321d7881b456b36eb398d (patch)
treed5bcf71835c398805464c083e2cf7a52668ed646 /certs
parent6c1394f30bae67d5dd8648a38679876ad4afc4f1 (diff)
downloadop-kernel-dev-bf1a85a8381a0f749aa321d7881b456b36eb398d.zip
op-kernel-dev-bf1a85a8381a0f749aa321d7881b456b36eb398d.tar.gz
Revert "net: ethernet: bcmgenet: use phydev from struct net_device"
This reverts commit 62469c76007e ("net: ethernet: bcmgenet: use phydev from struct net_device") because it causes GENETv1/2/3 adapters to expose the following behavior after an ifconfig down/up sequence: PING fainelli-linux (10.112.156.244): 56 data bytes 64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.352 ms 64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.472 ms (DUP!) 64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.496 ms (DUP!) 64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.517 ms (DUP!) 64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.536 ms (DUP!) 64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.557 ms (DUP!) 64 bytes from 10.112.156.244: seq=1 ttl=61 time=752.448 ms (DUP!) This was previously fixed by commit 5dbebbb44a6a ("net: bcmgenet: Software reset EPHY after power on") but the commit we are reverting was essentially making this previous commit void, here is why. Without commit 62469c76007e we would have the following scenario after an ifconfig down then up sequence: - bcmgenet_open() calls bcmgenet_power_up() to make sure the PHY is initialized *before* we get to initialize the UniMAC, this is critical to ensure the PHY is in a correct state, priv->phydev is valid, this code executes fine - second time from bcmgenet_mii_probe(), through the normal phy_init_hw() call (which arguably could be optimized out) Everything is fine in that case. With commit 62469c76007e, we would have the following scenario to happen after an ifconfig down then up sequence: - bcmgenet_close() calls phy_disonnect() which makes dev->phydev become NULL - when bcmgenet_open() executes again and calls bcmgenet_mii_reset() from bcmgenet_power_up() to initialize the internal PHY, the NULL check becomes true, so we do not reset the PHY, yet we keep going on and initialize the UniMAC, causing MAC activity to occur - we call bcmgenet_mii_reset() from bcmgenet_mii_probe(), but this is too late, the PHY is botched, and causes the above bogus pings/packets transmission/reception to occur Reported-by: Jaedon Shin <jaedon.shin@gmail.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'certs')
0 files changed, 0 insertions, 0 deletions
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