Port of ucLinux to the PSP. As the kernel doesn't really work, it will crash with a kernel panic

If it comes up to that point it means it works. It just can't find the root partition (sda1). It needs a Linux root file system to start of it. Usually ext2 or ext3, but if it's kernel 2.4, it can start from FAT file system with UMSDOS driver. Root file system can also be mounted from the file via loop device driver. You probably just need the right parameters and files to make it work.