As shown here:
http://kisskb.ellerman.id.au/kisskb/buildresult/6442834/
Commit b87077280b7271c5310237e127b0fe423d443e0f(mips: merge the
identical "return from syscall" per-ABI code) breaks MIPS.
I suggest that on arch/mips/kernel/entry.S:173 that you do:
s/bz/beqz/
I suspect that will fix the assembler error. Other than that, I make no
claims about the correctness of the code in general.
David Daney