Re: [PATCH v8 5/7] net/vmnet: implement bridged mode (vmnet-bridged)

[Vladislav Yaroshchuk]

вс, 23 янв. 2022 г. в 07:51, 李士林 <lslboyfuture@icloud.com>:

Hi:
    I develop a custom os use qemu and use macos as host, I use the net argument '-net nic,model=pcnet -net tap,ifname=tap0,script=no,downscript=no’ when run the qemu-system-i386,then I can get the network device in my custom os:

Please notice that `-net` is a legacy option
https://wiki.qemu.org/Documentation/Networking#The_legacy_-net_option

 

    pci_device_dump: vendor id:      0x1022
    pci_device_dump: device id:      0x2000
    pci_device_dump: class code:     0x20000
    pci_device_dump: revision id:    0x10
    pci_device_dump: multi function: 0
    pci_device_dump: card bus CIS pointer: 0
    pci_device_dump: subsystem vendor id: 0
    pci_device_dump: subsystem device id: 0
    pci_device_dump: expansion ROM base address: feb80000
    pci_device_dump: capability list pointer:  0
    pci_device_dump: irq line: 11
    pci_device_dump: irq pin:  1
    pci_device_dump: min Gnt: 6
    pci_device_dump: max Lat:  255
    pci_device_dump: bar 0:
    pci_device_bar_dump: type: io base address
    pci_device_bar_dump: base address: c000
    pci_device_bar_dump: len: 20
    pci_device_dump: bar 1:
    pci_device_bar_dump: type: mem base address
    pci_device_bar_dump: base address: febd1000
    pci_device_bar_dump: len: 20

I can send a message to the host from my custom os in qemu, but can’t receive a message from the host.

This is known issue:
https://gitlab.com/qemu-project/qemu/-/issues/335

 

so I rebuild the qemu use this patch, then I use the argument '-netdev vmnet-bridged,id=vmnet,ifname=en0’ run the qemu-system-i386 again, this time, I can’t get the network device either, I don’t know why, how to use vmnet-bridged to send message to host from my custom os and receive a message from the host, what should I do? thanks a lot!

It's normal behavior since you've specified a
network backend only. See the corresponding
QEMU documentation section:
https://wiki.qemu.org/Documentation/Networking#Network_Backends

Currently you have:
`-netdev vmnet-bridged,id=vmnet,ifname=en0`
You need add a device:
 `-netdev vmnet-bridged,id=vmnet,ifname=en0 -device pcnet,netdev=vmnet`

Supported devices can be listed with -device help:
`qemu-system-xxx -device help` 

--

Best Regards,

Vladislav Yaroshchuk