queue-4.14/nfp-bpf-fix-alu32-high-bits-clearance-bug.patch

   1 From ca10918a278b3ee96fe2540cb0cdc7dccc0ce26e Mon Sep 17 00:00:00 2001
   2 From: Jiong Wang <jiong.wang@netronome.com>
   3 Date: Fri, 22 Feb 2019 22:36:04 +0000
   4 Subject: nfp: bpf: fix ALU32 high bits clearance bug
   5
   6 [ Upstream commit f036ebd9bfbe1e91a3d855e85e05fc5ff156b641 ]
   7
   8 NFP BPF JIT compiler is doing a couple of small optimizations when jitting
   9 ALU imm instructions, some of these optimizations could save code-gen, for
  10 example:
  11
  12   A & -1 =  A
  13   A |  0 =  A
  14   A ^  0 =  A
  15
  16 However, for ALU32, high 32-bit of the 64-bit register should still be
  17 cleared according to ISA semantics.
  18
  19 Fixes: cd7df56ed3e6 ("nfp: add BPF to NFP code translator")
  20 Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
  21 Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
  22 Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
  23 Signed-off-by: Sasha Levin <sashal@kernel.org>
  24 ---
  25  drivers/net/ethernet/netronome/nfp/bpf/jit.c | 17 ++++++-----------
  26  1 file changed, 6 insertions(+), 11 deletions(-)
  27
  28 diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
  29 index 3105ee5bbf8e..c1ffec85817a 100644
  30 --- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
  31 +++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
  32 @@ -756,15 +756,10 @@ wrp_alu64_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
  33
  34  static int
  35  wrp_alu32_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
  36 -             enum alu_op alu_op, bool skip)
  37 +             enum alu_op alu_op)
  38  {
  39         const struct bpf_insn *insn = &meta->insn;
  40
  41 -       if (skip) {
  42 -               meta->skip = true;
  43 -               return 0;
  44 -       }
  45 -
  46         wrp_alu_imm(nfp_prog, insn->dst_reg * 2, alu_op, insn->imm);
  47         wrp_immed(nfp_prog, reg_both(insn->dst_reg * 2 + 1), 0);
  48
  49 @@ -1017,7 +1012,7 @@ static int xor_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  50
  51  static int xor_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  52  {
  53 -       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR, !meta->insn.imm);
  54 +       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR);
  55  }
  56
  57  static int and_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  58 @@ -1027,7 +1022,7 @@ static int and_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  59
  60  static int and_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  61  {
  62 -       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_AND, !~meta->insn.imm);
  63 +       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_AND);
  64  }
  65
  66  static int or_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  67 @@ -1037,7 +1032,7 @@ static int or_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  68
  69  static int or_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  70  {
  71 -       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_OR, !meta->insn.imm);
  72 +       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_OR);
  73  }
  74
  75  static int add_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  76 @@ -1047,7 +1042,7 @@ static int add_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  77
  78  static int add_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  79  {
  80 -       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_ADD, !meta->insn.imm);
  81 +       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_ADD);
  82  }
  83
  84  static int sub_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  85 @@ -1057,7 +1052,7 @@ static int sub_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  86
  87  static int sub_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  88  {
  89 -       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_SUB, !meta->insn.imm);
  90 +       return wrp_alu32_imm(nfp_prog, meta, ALU_OP_SUB);
  91  }
  92
  93  static int shl_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
  94 --
  95 2.19.1
  96