net: faraday: ftmac100: remove netif_running(netdev) check before disabling interrupts
authorVincent Chen <vincentc@andestech.com>
Wed, 21 Nov 2018 01:38:11 +0000 (09:38 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 13 Dec 2018 08:18:50 +0000 (09:18 +0100)
commitd0decb8d7cbb225336e043a63e9a8c72498834fd
treeb117b05dfcff1aaf4f52f8d0311a2b8ab47c43c1
parentf7a6fd087a300dabc4dbde84b1f2d4d0ac5173e0
net: faraday: ftmac100: remove netif_running(netdev) check before disabling interrupts

[ Upstream commit 426a593e641ebf0d9288f0a2fcab644a86820220 ]

In the original ftmac100_interrupt(), the interrupts are only disabled when
the condition "netif_running(netdev)" is true. However, this condition
causes kerenl hang in the following case. When the user requests to
disable the network device, kernel will clear the bit __LINK_STATE_START
from the dev->state and then call the driver's ndo_stop function. Network
device interrupts are not blocked during this process. If an interrupt
occurs between clearing __LINK_STATE_START and stopping network device,
kernel cannot disable the interrupts due to the condition
"netif_running(netdev)" in the ISR. Hence, kernel will hang due to the
continuous interruption of the network device.

In order to solve the above problem, the interrupts of the network device
should always be disabled in the ISR without being restricted by the
condition "netif_running(netdev)".

[V2]
Remove unnecessary curly braces.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/net/ethernet/faraday/ftmac100.c