From mboxrd@z Thu Jan 1 00:00:00 1970 From: Markos Chandras Subject: [PATCH 16/17] MIPS: bpf: Use 32 or 64-bit load instruction to load an address to register Date: Mon, 23 Jun 2014 10:38:59 +0100 Message-ID: <1403516340-22997-17-git-send-email-markos.chandras@imgtec.com> References: <1403516340-22997-1-git-send-email-markos.chandras@imgtec.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Markos Chandras , "David S. Miller" , Daniel Borkmann , "Alexei Starovoitov" , To: Return-path: Received: from mailapp01.imgtec.com ([195.59.15.196]:12059 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753182AbaFWJjo (ORCPT ); Mon, 23 Jun 2014 05:39:44 -0400 In-Reply-To: <1403516340-22997-1-git-send-email-markos.chandras@imgtec.com> Sender: netdev-owner@vger.kernel.org List-ID: When loading a pointer to a register we need to use the appropriate 32 or 64bit instruction to preserve the pointer's top 32bits. Cc: "David S. Miller" Cc: Daniel Borkmann Cc: Alexei Starovoitov Cc: netdev@vger.kernel.org Signed-off-by: Markos Chandras --- arch/mips/net/bpf_jit.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c index 4920e0fd05ee..d8dba7b523a5 100644 --- a/arch/mips/net/bpf_jit.c +++ b/arch/mips/net/bpf_jit.c @@ -447,6 +447,17 @@ static inline void emit_wsbh(unsigned int dst, unsigned int src, emit_instr(ctx, wsbh, dst, src); } +/* load address to register */ +static inline void emit_load_addr(unsigned int dst, unsigned int src, + int imm, struct jit_ctx *ctx) +{ + /* src contains the base addr of the 32/64-pointer */ + if (config_enabled(CONFIG_64BIT)) + emit_instr(ctx, ld, dst, imm, src); + else + emit_instr(ctx, lw, dst, imm, src); +} + /* load a function pointer to register */ static inline void emit_load_func(unsigned int reg, ptr imm, struct jit_ctx *ctx) @@ -1271,7 +1282,8 @@ jmp_cmp: /* A = skb->dev->ifindex */ ctx->flags |= SEEN_SKB | SEEN_A | SEEN_S0; off = offsetof(struct sk_buff, dev); - emit_load(r_s0, r_skb, off, ctx); + /* Load address of *dev member */ + emit_load_addr(r_s0, r_skb, off, ctx); /* error (0) in the delay slot */ emit_bcond(MIPS_COND_EQ, r_s0, r_zero, b_imm(prog->len, ctx), ctx); -- 2.0.0