Re: [Qemu-devel] 9p as rootfs

[mar.krzeminski]

So for some reason kernel expect that 9pfs channel will be named 
/dev/root (root= seem to be ignored).
Working command line:

Kernel: /root=/dev/root rootfstype=9p rootflags=trans=virtio rw/
Qemu: /-device virtio-9p-device,fsdev=host_fs,mount_tag=/dev/root -fsdev 
local,id=host_fs,security_model=none,path=////work/rootfs/
/
Thanks,
Marcin/
/
W dniu 23.09.2016 o 21:41, mar.krzeminski pisze:
> And most important, while mounting as roots, error is:
>
> [    1.086235] device: '9p-1': device_add
> [    1.087859] 9pnet_virtio: no channels available
> [    1.091619] device: '9p-1': device_unregister
> [    1.092783] device: '9p-1': device_create_release
> [    1.093534] VFS: Cannot open root device "host" or 
> unknown-block(0,0): error -2
>
> Thanks,
> Marcin
>
> W dniu 23.09.2016 o 21:38, mar.krzeminski pisze:
> > Hello,
> >
> > I have a problem in my custom arm machine to use 9p fs as a rootfs.
> >
> > 9p command line i qemu:
> >
> > /-device virtio-9p-device,fsdev=host_fs,mount_tag=hostfs -fsdev 
> > local,id=host_fs,security_model=none,path=/work/rootfs/
> >
> > Kernel cmd line:
> >
> > /--append "root=hostfs rootfstype=9p rootflags=trans=virtio noinitrd 
> > console=ttyS3,115200"
> >
> > /Device tree entry:
> >
> > /        virtio: address@hidden {//
> > //            compatible = "virtio,mmio";//
> > //            reg = <0xff0a4000 0x200>;//
> > //            interrupts = <0 72 1>;//
> > //            status = "okay";//
> > //        };
> >
> >
> > / I can mount this fs from kernel using fstab entry:
> > /hostfs               /mnt/host            9p trans=virtio          0  0
> >
> > /Do you have any idea what am I doing wrong?
> >
> > Thanks,
> > Marcin/
> > /