[hwsim/vm Error] Cannot open root device "root" or unknown-block(0,0): error -19

[Rahul Jain]

In my guest kernel config, CONFIG_VIRTIO & CONFIG_VIRTIO_PCI are enabled

My kernel Config is from "/boot/config-3.10.37-031037-generic"

I am having config for 3.10.37 kernel
i   linux-headers-3.10.37-031037                                                                                                   - Header files related to Linux kernel version 3.10.37                                                                                     
i   linux-headers-3.10.37-031037-generic                                                                                           - Linux kernel headers for version 3.10.37 on 64 bit x86 SM



------- Original Message -------
Sender : Johannes Berg<johannes at sipsolutions.net>
Date : Jun 18, 2015 18:26 (GMT+05:30)
Title : Re: [EDT] [hwsim/vm Error] Cannot open root device "root" or unknown-block(0,0): error -19

On Thu, 2015-06-18 at 12:34 +0000, Rahul Jain wrote:
> hello,
> 
> I am trying to execute vm-run.sh on Ubuntu-14.04 having 3.10 kernel.
> 
> I am getting below error:-
> -----------------------
> [    0.491374] VFS: Cannot open root device "root" or unknown-block(0,0): error -19 
> [    0.492342] Please append a correct "root=" boot option; here are the available partitions:
> [    0.493398] 0b00         1048575 sr0  driver: sr
> [    0.494018] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
> -----------------------
> 
> Kernel Command line is
> Command line: mac80211_hwsim.support_p2p_device=0 mac80211_hwsim.channels=1 mac80211_hwsim.radios=6 init=/home/Perforce/OSS/hostap/tests/hwsim/vm/..//vm/inside.sh testdir=/home/Perforce/OSS/hostap/tests/hwsim/vm/../ timewarp=0 console=ttyS1 root=/dev/root rootflags=trans=
> virtio,version=9p2000.u ro rootfstype=9p EPATH= ARGS=
> 
> 
> Any suggestions on how to fix this error?

Sounds like you compiled the guest kernel without proper virtio support.

johannes