[matheusmoreira]

In my case it was a static freestanding nolibc program, there was no dynamic linker or ELF interpreter. :)

The shell's execve jumps directly to the entry point I provided. The execve itself was segfaulting somehow. I couldn't think of anything to do short of running this entire thing in a virtual machine and tracing the kernel itself to see which branch of the ELF loader I was ending up in.