Thanks for the response. I managed to solve that issue. In my case, the issue was with the serial console. I had to specifically set the console option as kernel boot parameters otherwise, I was not able to see any output at the serial console. For example, I replaced the line multiboot /boot/kernel-x86_64-pc99 with multiboot /boot/kernel-x86_64-pc99 console_port="0x3f8" debug_port="0x3f8" and I could see the serial output. Also, I need to set the -DRELEASE=OFF when building; otherwise, you will have a release build and no serial console output. These things are not specifically mentioned in the seL4 documentation page. So, It took a lot of time for me to figure them out. Also, what kind of application did you run under seL4? I would like to run a custom kernel using seL4/Camkes, which is based on the limine bootloader. I know there are instructions in the CamKes project to run Linux under CamKes, but it is based on a bzimage and a .cpio archive, but I do not have those files. I have a bootloader, i.e., limine (BOOTX64.efi), and a kernel .elf file. The bootloader loads the kernel just like a normal boot. Any idea how this can be achieved?