QEMU Booting for kernel developement not working when using tcp 2222:22 to copy things

Issue

I am learning how to implement my own system call in linux kernel by following:

• Syscall Guide
• Custom Kernel Guide

for getting QEMU set up.

In the end, it tells us to run the following command to Redirect port 2222 on the host OS to the QEMU VM's port 22 which will let me copy files between QEMU and my linux:

qemu-system-x86_64 -m 64M -hda ../debian_squeeze_amd64_standard.qcow2 - append "root=/dev/sda1 console=tty0 console=ttyS0,115200n8" -kernel arch/ x86_64/boot/bzImage -nographic -net nic,vlan=1 -net user,vlan=1 -redir tcp: 2222::22

But I get the follwing error on my terminal when I run the code:

qemu-system-x86_64: -: invalid option

Help me out, I am a beginner. Thanks

Solution

In this part of your command line: "- append" -- you have an extra space between the "-" and the "append". QEMU command line options are generally of the form "-something". If you put a space in the middle then QEMU won't recognize what you've given it.

If you're following a tutorial and a command it gives you doesn't work then it's often a good idea to check it carefully for minor typos, or to copy-and-paste the command from the tutorial and try that.

Answered By - Peter Maydell