From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Date: Sat, 10 May 2014 10:15:37 -0700 > On 05/09/2014 04:18 PM, akpm@xxxxxxxxxxxxxxxxxxxx wrote: >> The mm-of-the-moment snapshot 2014-05-09-16-17 has been uploaded to >> >> http://www.ozlabs.org/~akpm/mmotm/ >> > > > uml defconfig on x86_64: (also happens in linux-next) > > net/core/filter.c:57:0: warning: "R8" redefined [enabled by default] > arch/x86/include/uapi/asm/ptrace-abi.h:38:0: note: this is the location of the previous definition > > Same warnings for R9 and R10. I'm going to commit the following to net-next to fix this, thanks Randy. ==================== [PATCH] net: filter: Fix redefinition warnings on x86-64. Do not collide with the x86-64 PTRACE user API namespace. net/core/filter.c:57:0: warning: "R8" redefined [enabled by default] arch/x86/include/uapi/asm/ptrace-abi.h:38:0: note: this is the location of the previous definition Fix by adding a BPF_ prefix to the register macros. Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> --- net/core/filter.c | 71 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 37 insertions(+), 34 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 9aaa05a..c442a0d 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -46,17 +46,17 @@ #include <linux/if_vlan.h> /* Registers */ -#define R0 regs[BPF_REG_0] -#define R1 regs[BPF_REG_1] -#define R2 regs[BPF_REG_2] -#define R3 regs[BPF_REG_3] -#define R4 regs[BPF_REG_4] -#define R5 regs[BPF_REG_5] -#define R6 regs[BPF_REG_6] -#define R7 regs[BPF_REG_7] -#define R8 regs[BPF_REG_8] -#define R9 regs[BPF_REG_9] -#define R10 regs[BPF_REG_10] +#define BPF_R0 regs[BPF_REG_0] +#define BPF_R1 regs[BPF_REG_1] +#define BPF_R2 regs[BPF_REG_2] +#define BPF_R3 regs[BPF_REG_3] +#define BPF_R4 regs[BPF_REG_4] +#define BPF_R5 regs[BPF_REG_5] +#define BPF_R6 regs[BPF_REG_6] +#define BPF_R7 regs[BPF_REG_7] +#define BPF_R8 regs[BPF_REG_8] +#define BPF_R9 regs[BPF_REG_9] +#define BPF_R10 regs[BPF_REG_10] /* Named registers */ #define A regs[insn->a_reg] @@ -383,10 +383,12 @@ select_insn: /* CALL */ JMP_CALL_0: - /* Function call scratches R1-R5 registers, preserves R6-R9, - * and stores return value into R0. + /* Function call scratches BPF_R1-BPF_R5 registers, + * preserves BPF_R6-BPF_R9, and stores return value + * into BPF_R0. */ - R0 = (__bpf_call_base + insn->imm)(R1, R2, R3, R4, R5); + BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3, + BPF_R4, BPF_R5); CONT; /* JMP */ @@ -478,7 +480,7 @@ select_insn: } CONT; JMP_EXIT_0: - return R0; + return BPF_R0; /* STX and ST and LDX*/ #define LDST(SIZEOP, SIZE) \ @@ -505,18 +507,19 @@ select_insn: atomic64_add((u64) X, (atomic64_t *)(unsigned long) (A + insn->off)); CONT; - LD_ABS_W: /* R0 = ntohl(*(u32 *) (skb->data + K)) */ + LD_ABS_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + K)) */ off = K; load_word: - /* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are only - * appearing in the programs where ctx == skb. All programs - * keep 'ctx' in regs[BPF_REG_CTX] == R6, sk_convert_filter() - * saves it in R6, internal BPF verifier will check that - * R6 == ctx. + /* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are + * only appearing in the programs where ctx == + * skb. All programs keep 'ctx' in regs[BPF_REG_CTX] + * == BPF_R6, sk_convert_filter() saves it in BPF_R6, + * internal BPF verifier will check that BPF_R6 == + * ctx. * - * BPF_ABS and BPF_IND are wrappers of function calls, so - * they scratch R1-R5 registers, preserve R6-R9, and store - * return value into R0. + * BPF_ABS and BPF_IND are wrappers of function calls, + * so they scratch BPF_R1-BPF_R5 registers, preserve + * BPF_R6-BPF_R9, and store return value into BPF_R0. * * Implicit input: * ctx @@ -526,39 +529,39 @@ load_word: * K == 32-bit immediate * * Output: - * R0 - 8/16/32-bit skb data converted to cpu endianness + * BPF_R0 - 8/16/32-bit skb data converted to cpu endianness */ ptr = load_pointer((struct sk_buff *) ctx, off, 4, &tmp); if (likely(ptr != NULL)) { - R0 = get_unaligned_be32(ptr); + BPF_R0 = get_unaligned_be32(ptr); CONT; } return 0; - LD_ABS_H: /* R0 = ntohs(*(u16 *) (skb->data + K)) */ + LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + K)) */ off = K; load_half: ptr = load_pointer((struct sk_buff *) ctx, off, 2, &tmp); if (likely(ptr != NULL)) { - R0 = get_unaligned_be16(ptr); + BPF_R0 = get_unaligned_be16(ptr); CONT; } return 0; - LD_ABS_B: /* R0 = *(u8 *) (ctx + K) */ + LD_ABS_B: /* BPF_R0 = *(u8 *) (ctx + K) */ off = K; load_byte: ptr = load_pointer((struct sk_buff *) ctx, off, 1, &tmp); if (likely(ptr != NULL)) { - R0 = *(u8 *)ptr; + BPF_R0 = *(u8 *)ptr; CONT; } return 0; - LD_IND_W: /* R0 = ntohl(*(u32 *) (skb->data + X + K)) */ + LD_IND_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + X + K)) */ off = K + X; goto load_word; - LD_IND_H: /* R0 = ntohs(*(u16 *) (skb->data + X + K)) */ + LD_IND_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + X + K)) */ off = K + X; goto load_half; - LD_IND_B: /* R0 = *(u8 *) (skb->data + X + K) */ + LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + X + K) */ off = K + X; goto load_byte; @@ -1001,7 +1004,7 @@ do_pass: *insn = BPF_ALU64_REG(BPF_MOV, BPF_REG_TMP, BPF_REG_A); insn++; - /* A = R0 = *(u8 *) (skb->data + K) */ + /* A = BPF_R0 = *(u8 *) (skb->data + K) */ *insn = BPF_LD_ABS(BPF_B, fp->k); insn++; -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
