[LITMUS^RT] Question about using QEMU with Litmus

[Björn Brandenburg]

> On 17 Nov 2015, at 05:26, Shuai Zhao <zs673 at york.ac.uk> wrote:
> 
> I am now doing a project that requires a modification of Litmus source. I want to with QEMU to debug the litmus kernel but encountered an issue. 
> 
> What I did is download the image from litmus website and compiled the kernel with the desired kernel configuration. Then I tried to boot up the kernel by this command:
> 
> qemu-system-x86_64 -enable-kvm -cpu host -smp 2 -hda /home/shuai/Desktop/ubuntu.backing.qcow2.img -m 1024 -name "shuai-litmus" -nographic -kernel "/home/shuai/Desktop/litmus-rt/arch/x86_64/boot/bzImage" -append "console=ttyS0,115200 root=/dev/sda1" -gdb tcp::12345 -net nic -net user,hostfwd=::2222-:22
> 
> However, I cannot boot up the kernel and got the following error message:
> 
> mount: wrong fs type, bad option, bad superblock on 10.0.0.2:/var/nfs,
>        missing codepage or helper program, or other error
>        (for several filesystems (e.g. nfs, cifs) you might
>        need a /sbin/mount.<type> helper program)
>        In some cases useful info is found in syslog - try
>        dmesg | tail  or so
> 
> mountall: mount /var/nfs [383] terminated with status 32
> modprobe: FATAL: Could not load /lib/modules/4.1.3/modules.dep: No such file or directory
> 
> modprobe: FATAL: Could not load /lib/modules/4.1.3/modules.dep: No such file or directory
> 
> I wonder what should I do to fix this? I cannot allocate the modules.dep in the DIR of litmus source.



Dear Shuai,

this looks like your kernel config is missing the module for the file system that your root FS uses (NFS?). This is not a LITMUS^RT-specific problem. It’s best practice to first compile a regular “vanilla” kernel and  to get it to boot. Once you can boot a “vanilla” kernel, moving the .config to LITMUS^RT should not be a problem.

Best regards,
Björn


PS: In the future, please subscribe before posting to this list.