From bef8968df8a6e3eb91081d68affc64b8d87d5721 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 11 Jul 2018 10:32:33 +0100 Subject: [PATCH] ARM: net: bpf: always use odd/even register pair Always use an odd/even register pair for our 64-bit registers, so that we're able to use the double-word load/store instructions in the future. Signed-off-by: Russell King Signed-off-by: Daniel Borkmann --- arch/arm/net/bpf_jit_32.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index f0cad96..006ff96 100644 --- a/arch/arm/net/bpf_jit_32.c +++ b/arch/arm/net/bpf_jit_32.c @@ -47,27 +47,27 @@ * The callee saved registers depends on whether frame pointers are enabled. * With frame pointers (to be compliant with the ABI): * - * high - * original ARM_SP => +------------------+ \ - * | pc | | - * current ARM_FP => +------------------+ } callee saved registers - * |r4-r8,r10,fp,ip,lr| | - * +------------------+ / - * low + * high + * original ARM_SP => +--------------+ \ + * | pc | | + * current ARM_FP => +--------------+ } callee saved registers + * |r4-r9,fp,ip,lr| | + * +--------------+ / + * low * * Without frame pointers: * - * high - * original ARM_SP => +------------------+ - * | r4-r8,r10,fp,lr | callee saved registers - * current ARM_FP => +------------------+ - * low + * high + * original ARM_SP => +--------------+ + * | r4-r9,fp,lr | callee saved registers + * current ARM_FP => +--------------+ + * low * * When popping registers off the stack at the end of a BPF function, we * reference them via the current ARM_FP register. */ #define CALLEE_MASK (1 << ARM_R4 | 1 << ARM_R5 | 1 << ARM_R6 | \ - 1 << ARM_R7 | 1 << ARM_R8 | 1 << ARM_R10 | \ + 1 << ARM_R7 | 1 << ARM_R8 | 1 << ARM_R9 | \ 1 << ARM_FP) #define CALLEE_PUSH_MASK (CALLEE_MASK | 1 << ARM_LR) #define CALLEE_POP_MASK (CALLEE_MASK | 1 << ARM_PC) @@ -157,7 +157,7 @@ static const s8 bpf2a32[][2] = { * for constant blindings and others. */ [TMP_REG_1] = {ARM_R7, ARM_R6}, - [TMP_REG_2] = {ARM_R10, ARM_R8}, + [TMP_REG_2] = {ARM_R9, ARM_R8}, /* Tail call count. Stored on stack scratch space. */ [TCALL_CNT] = {STACK_OFFSET(BPF_TC_HI), STACK_OFFSET(BPF_TC_LO)}, /* temporary register for blinding constants. -- 2.7.4