[PATCH AUTOSEL for 4.4 028/167] vmxnet3: ensure that adapter is in proper state during force_close

Sasha Levin
2018-03-19T17:30:39Z

From: Neil Horman <nhorman@tuxdriver.com>

[ Upstream commit 1c4d5f51a812a82de97beee24f48ed05c65ebda5 ]

There are several paths in vmxnet3, where settings changes cause the
adapter to be brought down and back up (vmxnet3_set_ringparam among
them). Should part of the reset operation fail, these paths call
vmxnet3_force_close, which enables all napi instances prior to calling
dev_close (with the expectation that vmxnet3_close will then properly
disable them again). However, vmxnet3_force_close neglects to clear
VMXNET3_STATE_BIT_QUIESCED prior to calling dev_close. As a result
vmxnet3_quiesce_dev (called from vmxnet3_close), returns early, and
leaves all the napi instances in a enabled state while the device itself
is closed. If a device in this state is activated again, napi_enable
will be called on already enabled napi_instances, leading to a BUG halt.

The fix is to simply enausre that the QUIESCED bit is cleared in
vmxnet3_force_close to allow quesence to be completed properly on close.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Shrikrishna Khare <skhare@vmware.com>
CC: "VMware, Inc." <pv-drivers@vmware.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/net/vmxnet3/vmxnet3_drv.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index 82bf85ae5d08..419c045d0752 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -2789,6 +2789,11 @@ vmxnet3_force_close(struct vmxnet3_adapter *adapter)
/* we need to enable NAPI, otherwise dev_close will deadlock */
for (i = 0; i < adapter->num_rx_queues; i++)
napi_enable(&adapter->rx_queue[i].napi);
+ /*
+ * Need to clear the quiesce bit to ensure that vmxnet3_close
+ * can quiesce the device properly
+ */
+ clear_bit(VMXNET3_STATE_BIT_QUIESCED, &adapter->state);
dev_close(adapter->netdev);
}

--
2.14.1