netdev - [PATCH bpf-next 10/13] bpf, mips64: remove obsolete exception handling from div/mod

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Date:   Fri, 26 Jan 2018 23:33:45 +0100
From:   Daniel Borkmann <daniel@...earbox.net>
To:     ast@...nel.org
Cc:     netdev@...r.kernel.org, Daniel Borkmann <daniel@...earbox.net>,
        David Daney <david.daney@...ium.com>
Subject: [PATCH bpf-next 10/13] bpf, mips64: remove obsolete exception handling from div/mod

Since we've changed div/mod exception handling for src_reg in
eBPF verifier itself, remove the leftovers from mips64 JIT.

Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Cc: David Daney <david.daney@...ium.com>
---
 arch/mips/net/ebpf_jit.c | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c
index 4e34703..296f1410 100644
--- a/arch/mips/net/ebpf_jit.c
+++ b/arch/mips/net/ebpf_jit.c
@@ -860,11 +860,6 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
 			break;
 		case BPF_DIV:
 		case BPF_MOD:
-			b_off = b_imm(exit_idx, ctx);
-			if (is_bad_offset(b_off))
-				return -E2BIG;
-			emit_instr(ctx, beq, src, MIPS_R_ZERO, b_off);
-			emit_instr(ctx, movz, MIPS_R_V0, MIPS_R_ZERO, src);
 			emit_instr(ctx, ddivu, dst, src);
 			if (bpf_op == BPF_DIV)
 				emit_instr(ctx, mflo, dst);
@@ -943,11 +938,6 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
 			break;
 		case BPF_DIV:
 		case BPF_MOD:
-			b_off = b_imm(exit_idx, ctx);
-			if (is_bad_offset(b_off))
-				return -E2BIG;
-			emit_instr(ctx, beq, src, MIPS_R_ZERO, b_off);
-			emit_instr(ctx, movz, MIPS_R_V0, MIPS_R_ZERO, src);
 			emit_instr(ctx, divu, dst, src);
 			if (bpf_op == BPF_DIV)
 				emit_instr(ctx, mflo, dst);
-- 
2.9.5