Re: [PATCH bpf-next v2] m68k, bpf: Add initial BPF JIT compiler support

> diff --git a/arch/m68k/net/bpf_jit_comp.c b/arch/m68k/net/bpf_jit_comp.c
> new file mode 100644
> index 000000000000..98cef53c6f39
> --- /dev/null
> +++ b/arch/m68k/net/bpf_jit_comp.c

[ ... ]

> +static void emit_alu64_k(const struct bpf_insn *insn, struct jit_ctx *ctx)
> +{

[ ... ]

> +	switch (BPF_OP(insn->code)) {

[ ... ]

> +	case BPF_XOR:
> +		emit_16(ctx, 0xb180 | (s_lo << 9) | d_lo);		/* eor.l d_lo, s_lo */
> +		emit_16(ctx, 0xb180 | (s_hi << 9) | d_hi);		/* eor.l d_hi, s_hi */
> +		break;

This isn't a bug, but the operand order in these comments is reversed.
The m68k encoding 0xb180 | (s_lo << 9) | d_lo represents 'eor.l s_lo,
d_lo', not 'eor.l d_lo, s_lo'. Compare with the identical bytecode in
emit_alu64_x's BPF_XOR case which correctly comments it as 'eor.l s_lo,
d_lo', and emit_alu32_x's BPF_XOR which uses 'eor.l src, dst'.


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See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md

CI run summary: https://github.com/kernel-patches/bpf/actions/runs/25287107687