Hello everyone,
       
   I have a problem related to booting the qemuarm image inside eclipse in order to test some applications I develop.
I built a custom image (it inherits core-image-minimal, used latest linux kernel 4.8, adds a few extra packages, such as boost, libstd, libmodbus etc.) which runs succesfully inside yocto with runqemu command (as ext4 fstype, also I have an extra ext4 partition made which is added with -drive parameter to runqemu command).
In order to use the created image inside Eclipse, I have extracted the rootfs separately and used the folowing trick to compile succesfully the application I am working at (https://wiki.yoctoproject.org/wiki/TipsAndTricks/RunningEclipseAgainstBuiltImage#Why_SDK_Image). I am using Eclipse Luna.
I have set all the necessary parameters inside, qemu starts, but at boot it hangs  at the following lines:

md: Waiting for all devices to be available before autodetect
md: If you don't use raid, use raid=noautodetect
md: Scanned 0 and added 0 devices.
md: autorun..
md: autorun DONE.

After a while it shows the following:

VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "nfs" or unknown-block(2,0): error -6
Please append a correct "root=" boot option; here are the available partitions:
0100     4096  ram0 (driver?)
......
fd00    4096  vda    driver:virtio_blk
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
....

  Inside the console terminal (the one that starts the qemu console) it shows the following:


Assuming /home/user/myrootfs-rootfs/rootfs is an nfs rootfs

Continuing with the following parameters:
KERNEL: [/home/user/test/yocto-krogoth/build-qemuarm/tmp/deploy/images/qemuarm/zImage-qemuarm.bin]
ROOTFS: [/home/user/myrootfs-rootfs/rootfs]
FSTYPE: [nfs]
Acquiring lockfile for tap0...
Acquiring lockfile for tap1...
Acquiring lockfile for tap2...
Acquiring lockfile for tap4...
Acquiring lockfile for tap3...
Acquiring lockfile for tap5...
Using preconfigured tap device 'tap5'
If this is not intended, touch /tmp/qemu-tap-locks/tap5.skip to make runqemu skip tap5.
runqemu-export-rootfs restart /home/user/myrootfs-rootfs/rootfs
No PID file, not stopping rpc.nfsd
Creating exports file...
Starting User Mode nfsd

 /home/user/test/yocto-krogoth/build-qemuarm/tmp/sysroots/x86_64-linux/usr/bin/pseudo -P /home/user/test/yocto-krogoth/build-qemuarm/tmp/sysroots/x86_64-linux/usr /home/user/test/yocto-krogoth/build-qemuarm/tmp/sysroots/x86_64-linux/usr/bin/unfsd -p -N -i /home/user/.runqemu-sdk/nfs5.pid -e /home/user/.runqemu-sdk/exports5 -x 11116 -n 3059 -y 21116 -m 3058
 
On your target please remember to add the following options for NFS
nfsroot=IP_ADDRESS:/home/user/myrootfs-rootfs/rootfs,nfsvers=3,port=,mountprog=,nfsprog=,udp,mountport=
Running qemu-system-arm...
/home/user/test/yocto-krogoth/build-qemuarm/tmp/sysroots/x86_64-linux/usr/bin/qemu-system-arm -kernel /home/user/test/yocto-krogoth/build-qemuarm/tmp/deploy/images/qemuarm/zImage-qemuarm.bin -net nic,model=virtio -net tap,vlan=0,ifname=tap5,script=no,downscript=no -M versatilepb --no-reboot -show-cursor -usb -usbdevice tablet -no-reboot -dtb /home/user/test/yocto-krogoth/build-qemuarm/tmp/deploy/images/qemuarm/zImage-versatile-pb.dtb -drive file=/home/user/test/yocto-krogoth/build-qemuarm/tmp/deploy/images/qemuarm/data.ext4,if=virtio,format=raw -m 128 -serial mon:vc -serial null -append "root=/dev/nfs nfsroot=192.168.7.1:/home/user/myrootfs-rootfs/rootfs,nfsvers=3,port=3059,mountprog=21116,nfsprog=11116,udp,mountport=3058 rw console=ttyAMA0,115200 ip=192.168.7.12::192.168.7.11:255.255.255.0 mem=128M console=tty"
vpb_sic_write: Bad register offset 0x2c



     I have rpcbind enabled (it has been addded the -i option as described in the documentation). Inside the kernel's defconfig the NFS support is enabled.
     unfsd it listens on port 3049 (checked with netstat).
     Inside syslog I have a warning related to it:
        Nov 18 13:37:04 unknown unfsd[27672]: Warning: unknown exports option `async' ignored
        
    What should be done in order to succesfully boot the non SDK image inside Eclipse with the NFS file system?
    
     Thanks in advance!