iavf: do not process adminq tasks when __IAVF_IN_REMOVE_TASK is set

Prevent schedule operations for adminq during device remove and when
__IAVF_IN_REMOVE_TASK flag is set. Currently, the iavf_down function
adds operations for adminq that shouldn't be processed when the device
is in the __IAVF_REMOVE state.

Reproduction:

echo 4 > /sys/bus/pci/devices/0000:17:00.0/sriov_numvfs
ip link set dev ens1f0 vf 0 trust on
ip link set dev ens1f0 vf 1 trust on
ip link set dev ens1f0 vf 2 trust on
ip link set dev ens1f0 vf 3 trust on

ip link set dev ens1f0 vf 0 mac 00:22:33:44:55:66
ip link set dev ens1f0 vf 1 mac 00:22:33:44:55:67
ip link set dev ens1f0 vf 2 mac 00:22:33:44:55:68
ip link set dev ens1f0 vf 3 mac 00:22:33:44:55:69

echo 0000:17:02.0 > /sys/bus/pci/devices/0000\:17\:02.0/driver/unbind
echo 0000:17:02.1 > /sys/bus/pci/devices/0000\:17\:02.1/driver/unbind
echo 0000:17:02.2 > /sys/bus/pci/devices/0000\:17\:02.2/driver/unbind
echo 0000:17:02.3 > /sys/bus/pci/devices/0000\:17\:02.3/driver/unbind
sleep 10
echo 0000:17:02.0 > /sys/bus/pci/drivers/iavf/bind
echo 0000:17:02.1 > /sys/bus/pci/drivers/iavf/bind
echo 0000:17:02.2 > /sys/bus/pci/drivers/iavf/bind
echo 0000:17:02.3 > /sys/bus/pci/drivers/iavf/bind

modprobe vfio-pci
echo 8086 154c > /sys/bus/pci/drivers/vfio-pci/new_id

qemu-system-x86_64 -accel kvm -m 4096 -cpu host \
-drive file=centos9.qcow2,if=none,id=virtio-disk0 \
-device virtio-blk-pci,drive=virtio-disk0,bootindex=0 -smp 4 \
-device vfio-pci,host=17:02.0 -net none \
-device vfio-pci,host=17:02.1 -net none \
-device vfio-pci,host=17:02.2 -net none \
-device vfio-pci,host=17:02.3 -net none \
-daemonize -vnc :5

Current result:
There is a probability that the mac of VF in guest is inconsistent with
it in host

Expected result:
When passthrough NIC VF to guest, the VF in guest should always get
the same mac as it in host.

Fixes: 14756b2 ("iavf: Fix __IAVF_RESETTING state usage")
Signed-off-by: Radoslaw Tyl <[email protected]>
Tested-by: Rafal Romanowski <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

Author: rtylx

drivers/net/ethernet/intel/iavf/iavf_main.c

@@ -1421,7 +1421,8 @@ void iavf_down(struct iavf_adapter *adapter)
 	iavf_clear_fdir_filters(adapter);
 	iavf_clear_adv_rss_conf(adapter);
 
-	if (!(adapter->flags & IAVF_FLAG_PF_COMMS_FAILED)) {
+	if (!(adapter->flags & IAVF_FLAG_PF_COMMS_FAILED) &&
+	    !(test_bit(__IAVF_IN_REMOVE_TASK, &adapter->crit_section))) {
 		/* cancel any current operation */
 		adapter->current_op = VIRTCHNL_OP_UNKNOWN;
 		/* Schedule operations to close down the HW. Don't wait