set up qemu for kernel development
Preparation
Create one Debian image as rootfs. Two methods are in the following:
Method One
Use one script in syzkaller to generate debian image. It could generate wheezy, jessie, stretch release.
However, for jessie or above releases, you need to take care of kernel configuration. See another post
Method Two
IMG=test_stretch.img
DIR=stretch
qemu-img create $IMG 1g
sudo mkfs.ext4 $IMG
mkdir -p $DIR
sudo mount -o loop $IMG $DIR
sudo debootstrap --arch amd64 stretch $DIR
sudo umount $DIR
rmdir $DIR
The above instruction sequence is copied from Reference 1.
There is no error message when creating rootfs. At last, I try to boot one kernel with that rootfs.
Experiment
Test on the current kernel
$ qemu-system-x86_64 -kernel /boot/vmlinuz-`uname -r` \
-hda qemu-image.img -append "console=ttyS0 root=/dev/sda"
Result:
Succeed in both Debian and Ubuntu
Test on own building kernel
$ git clone --depth=1 git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
$ cd linux
$ make x86_64_defconfig
$ make kvmconfig
$ make -j4
$ qemu-system-x86_64 -kernel linux/arch/x86/boot/bzImage \
-hda qemu-image.img -append "console=ttyS0 root=/dev/sda"
Result:
Succeed in Both Ubuntu and Debian
Other options
You could use options --enable-kvm(speed up with KVM) and --nographic(without GUI).