I have downloaded and compiled vanilla linux kernel (3.7.1)
I used busybox for ramdisk then I booted it using QEMU.
This is my QEMU command line
qemu-system-i386 -kernel bzImage -initrd ramdisk.img -append "root=/dev/ram rw console=ttyS0 rdinit=/bin/ash" -nographic -net nic -net user
everything goes well.
However, I can't use networking on vanilla kernel with busybox.
'ifup eth0' tells me
/ # ifup eth0
ip: SIOCGIFFLAGS: No such device
I googled the Internet but can' get any clue...
some advice would be nice
thank you in advance.
Most probably there is no driver (in your example is should be e1000) loaded or the device has another name.
In /sys/class/net/ you should find a listing of all available net-devices.
If there is none (besides lo) the driver is not loaded.
In qemu monitor type "info pci" and it will show you the PCI-address of your ethernet card. It should look like this:
...
Bus 0, device 3, function 0:
Ethernet controller: PCI device 8086:100e
...
This device corresponds to /sys/devices/pci0000:00/0000:00:03.0/.
The files "vendor" and "device" must contain "0x8086" and "0x100e" which is the PCI-id from above and by which the kernel determines the driver to load.
Try to load it manually with "modprobe e1000" or insmod. If loaded there must be a symlink named "driver". If not "dmesg" should give you the reason why not.
