I am trying to compile and boot Linux Kernel v3.19 (64-bit version) using -
make defconfig make kvmconfig make -j8The compilation works out without any errors but it doesn't boot inside qemu or my host machine. I use the following command line parameters to linux: "debug earlyprintk loglevel=7"
The boot hangs at the point -
Booting from ROM... early console in setup code early console in decompress_kernel Decompressing Linux... Parking ELF... done. Booting the kernel .
Things I have tried so far -
- Interestingly if I uncheck the 64-bit build in config (from make menuconfig), the resulting 32-bit kernel boots correctly.
- Have tried running qemu with different cpus (host) + with & without kvm.
sudo qemu-system-x86_64 -m 4G -append 'debug earlyprintk loglevel=7' -kernel arch/x86/boot/bzImage -cpu host -enable-kvm
I know the kernel will panic because of no root filesystem, but it happens later in the boot process. I am basing this from booting the 32 bit version of the kernel which prints out a lot of stuff and then panics due to no vfs_root.
- The 64-bit versions of kernel v4.2 and above don't have this issue - meaning they boot correctly.
Any pointers to what the mistake is?
Linux Kernel Repo used: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
QEMU version: QEMU emulator version 2.5.0 (Debian 1:2.5+dfsg-5ubuntu10.11