4.14-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 3.19.2 / sh_eth-fix-lost-mac-address-on-kexec.patch

From foo@baz Wed Mar 11 11:44:33 CET 2015
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Fri, 27 Feb 2015 17:16:26 +0100
Subject: sh_eth: Fix lost MAC address on kexec

From: Geert Uytterhoeven <geert+renesas@glider.be>

[ Upstream commit a14c7d15ca91b444e77df08b916befdce77562ab ]

Commit 740c7f31c094703c ("sh_eth: Ensure DMA engines are stopped before
freeing buffers") added a call to sh_eth_reset() to the
sh_eth_set_ringparam() and sh_eth_close() paths.

However, setting the software reset bit(s) in the EDMR register resets
the MAC Address Registers to zero. Hence after kexec, the new kernel
doesn't detect a valid MAC address and assigns a random MAC address,
breaking DHCP.

Set the MAC address again after the reset in sh_eth_dev_exit() to fix
this.

Tested on r8a7740/armadillo (GETHER) and r8a7791/koelsch (FAST_RCAR).

Fixes: 740c7f31c094703c ("sh_eth: Ensure DMA engines are stopped before freeing buffers")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/renesas/sh_eth.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -1392,6 +1392,9 @@ static void sh_eth_dev_exit(struct net_d
 	msleep(2); /* max frame time at 10 Mbps < 1250 us */
 	sh_eth_get_stats(ndev);
 	sh_eth_reset(ndev);
+
+	/* Set MAC address again */
+	update_mac_address(ndev);
 }
 
 /* free Tx skb function */