Re: [PATCH bpf-next 1/8] arm32, bpf: add support for 32-bit offset jmp instruction

On Tue, Sep 05, 2023 at 09:06:14PM +0000, Puranjay Mohan wrote:

The cpuv4 adds unconditional jump with 32-bit offset where the immediate field of the instruction is to be used to calculate the jump offset.

BPF_JA | BPF_K | BPF_JMP32 => gotol +imm => PC += imm.

Signed-off-by: Puranjay Mohan puranjay12@gmail.com

arch/arm/net/bpf_jit_32.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index 6a1c9fca5260..b26579da770e 100644 --- a/arch/arm/net/bpf_jit_32.c +++ b/arch/arm/net/bpf_jit_32.c @@ -1761,10 +1761,15 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) break; /* JMP OFF */ case BPF_JMP | BPF_JA:

• case BPF_JMP32 | BPF_JA: {

• if (off == 0)
  

• if (BPF_CLASS(code) == BPF_JMP32 && imm != 0)
  

• 	jmp_offset = bpf2a32_offset(i + imm, i, ctx);
  

• else if (BPF_CLASS(code) == BPF_JMP &&  off != 0)
  

Please tidy up the coding style - one space between "&&" and "off"

Thanks.