When start testpmd with two hns3 VFs(0000:bd:01.0, 0000:bd:01.7), and
then execute the following commands:
testpmd> create bonded device 1 0
testpmd> set bonding mac_addr 2 3c:12:34:56:78:9a
testpmd> add bonding slave 0 2
testpmd> add bonding slave 1 2
testpmd> set portmask 0x4
testpmd> port start 2
It will occurs the following error in a low probability:
0000:bd:01.0 hns3_get_mbx_resp(): VF could not get mbx(3,0)
head(16) tail(15) lost(1) from PF in_irq:0
0000:bd:01.0 hns3vf_set_default_mac_addr(): Failed to set mac
addr(3C:**:**:**:78:9A) for vf: -62
mac_address_slaves_update(1541) - Failed to update port Id 0
MAC address
The problem replay:
1. The 'port start 2' command will start slave ports and then set slave
mac address, the function call flow: bond_ethdev_start ->
mac_address_slaves_update.
2. There are also a monitor task which running in intr thread will check
slave ports link status and update slave ports mac address, the
function call flow: bond_ethdev_slave_link_status_change_monitor ->
bond_ethdev_lsc_event_callback -> mac_address_slaves_update.
3. Because the above step1&2 running on different threads, they may both
call drivers ops mac_addr_set which is hns3vf_set_default_mac_addr.
4. hns3vf_set_default_mac_addr will first acquire hw.lock and then send
mailbox to PF and wait PF's response message. Note: the PF's
response is an independent message which will received in hw.cmq.crq,
the receiving operation can only performed in intr thread.
5. So if the step1 operation hold the hw.lock and try get response
message, and step2 operation try acquire the hw.lock and so it can't
process the response message, this will lead to step1 fail.
The solution:
1. make all threads could process the mailbox response message, which
protected by the hw.cmq.crq.lock.
2. use the following rules to avoid deadlock:
2.1. ensure use the correct locking sequence: hw.lock >
hw.mbx_resp.lock > hw.cmq.crq.lock.
2.2. make sure don't acquire such as hw.lock & hw.mbx_resp.lock again
when process mailbox response message.
Fixes: 463e748964f5 ("net/hns3: support mailbox")
Cc: stable@dpdk.org
Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
76a3836b98