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 08:16:14 +0000 (09:16 +0100)
commit549e3c24ac348249bd5169382efc0ef8b63da466
tree04b3a28d01c51234ff9b6ff18e5a27e26728a618
parentd69eb98a86c0ed560b303a1a078e668d230d9d39
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