Shutting down interface eth0: bridge br0 is still up; can't delete it

Scenario Description: currently, in the centos version, the Network Bridge br0 is configured with eth0, and the following problems are found:
Ifconfig

Br0 link encap: Ethernet hwaddr 00: 0C: 29: 5D: 07: 15

Inet ADDR: 192.168.40.250 bcast: 192.168.40.255 mask: 255.255.255.0

Inet6 ADDR: fe80: 20c: 29ff: fe5d: 715/64 scope: Link

Up broadcast running Multicast MTU: 1500 Metric: 1

RX packets: 290 errors: 0 dropped: 0 overruns: 0 frame: 0

TX packets: 10 errors: 0 dropped: 0 overruns: 0 carrier: 0

Collisions: 0 txqueuelen: 0

RX Bytes: 18299 (17.8 kib) TX Bytes: 636 (636.0 B)

Eth0 link encap: Ethernet hwaddr 00: 0C: 29: 5D: 07: 15

Inet ADDR: 192.168.40.250 bcast: 192.168.40.255 mask: 255.255.255.0

Inet6 ADDR: fe80: 20c: 29ff: fe5d: 715/64 scope: Link

Up broadcast running Multicast MTU: 1500 Metric: 1

RX packets: 49743 errors: 0 dropped: 0 overruns: 0 frame: 0

TX packets: 404 errors: 0 dropped: 0 overruns: 0 carrier: 0

Collisions: 0 FIG: 1000

RX Bytes: 3793317 (3.6 MIB) TX Bytes: 157382 (153.6 kib)

Interrupt: 19 base address: 0x2024

# Ethtool br0

Settings for br0:

Link detected: Yes

# Ethtool eth0

Settings for eth0:

Supported ports: [TP]

Supported link modes: 1000 Baset/full

Supported pause frame use: No

Supports auto-negotiation: No

Advertised link modes: not reported

Advertised pause frame use: No

Advertised auto-negotiation: No

Speed: 1000 MB/S

Duplex: full

Port: Twisted Pair

Phyad: 0

Transceiver: Internal

Auto-negotiation: Off

MDI-X: Unknown

Link detected: Yes

Restart the network: Service Network restart

The first attempt failed,