HelenOS sources

gp_fault          220 kernel/arch/amd64/src/interrupt.c 	exc_register(VECTOR_GP, "gp_fault", true, (iroutine_t) gp_fault);
gp_fault          242 kernel/arch/ia32/src/interrupt.c 	exc_register(VECTOR_GP, "gp_fault", true, (iroutine_t) gp_fault);
HelenOS homepage, sources at GitHub