diff options
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 29 |
1 files changed, 15 insertions, 14 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 0abd082786e7..d926ca637d8d 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1138,16 +1138,15 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image case BPF_ALU64 | BPF_RSH | BPF_X: case BPF_ALU64 | BPF_ARSH | BPF_X: - /* Check for bad case when dst_reg == rcx */ - if (dst_reg == BPF_REG_4) { - /* mov r11, dst_reg */ - EMIT_mov(AUX_REG, dst_reg); - dst_reg = AUX_REG; - } - if (src_reg != BPF_REG_4) { /* common case */ - EMIT1(0x51); /* push rcx */ - + /* Check for bad case when dst_reg == rcx */ + if (dst_reg == BPF_REG_4) { + /* mov r11, dst_reg */ + EMIT_mov(AUX_REG, dst_reg); + dst_reg = AUX_REG; + } else { + EMIT1(0x51); /* push rcx */ + } /* mov rcx, src_reg */ EMIT_mov(BPF_REG_4, src_reg); } @@ -1159,12 +1158,14 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image b3 = simple_alu_opcodes[BPF_OP(insn->code)]; EMIT2(0xD3, add_1reg(b3, dst_reg)); - if (src_reg != BPF_REG_4) - EMIT1(0x59); /* pop rcx */ + if (src_reg != BPF_REG_4) { + if (insn->dst_reg == BPF_REG_4) + /* mov dst_reg, r11 */ + EMIT_mov(insn->dst_reg, AUX_REG); + else + EMIT1(0x59); /* pop rcx */ + } - if (insn->dst_reg == BPF_REG_4) - /* mov dst_reg, r11 */ - EMIT_mov(insn->dst_reg, AUX_REG); break; case BPF_ALU | BPF_END | BPF_FROM_BE: |