Merge branch 'for-4.5/lightnvm' of git://git.kernel.dk/linux-block

[deliverable/linux.git] / arch / arm / net / bpf_jit_32.c

diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index 591f9db3bf4048a4d727f195e4e2fb95e4ca06c4..93d0b6d0b63eede5f36de91428bb181bab2e0971 100644 (file)
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -187,19 +187,6 @@ static inline int mem_words_used(struct jit_ctx *ctx)
        return fls(ctx->seen & SEEN_MEM);
 }
 
-static inline bool is_load_to_a(u16 inst)
-{
-       switch (inst) {
-       case BPF_LD | BPF_W | BPF_LEN:
-       case BPF_LD | BPF_W | BPF_ABS:
-       case BPF_LD | BPF_H | BPF_ABS:
-       case BPF_LD | BPF_B | BPF_ABS:
-               return true;
-       default:
-               return false;
-       }
-}
-
 static void jit_fill_hole(void *area, unsigned int size)
 {
        u32 *ptr;
@@ -211,7 +198,6 @@ static void jit_fill_hole(void *area, unsigned int size)
 static void build_prologue(struct jit_ctx *ctx)
 {
        u16 reg_set = saved_regs(ctx);
-       u16 first_inst = ctx->skf->insns[0].code;
        u16 off;
 
 #ifdef CONFIG_FRAME_POINTER
@@ -241,7 +227,7 @@ static void build_prologue(struct jit_ctx *ctx)
                emit(ARM_MOV_I(r_X, 0), ctx);
 
        /* do not leak kernel data to userspace */
-       if ((first_inst != (BPF_RET | BPF_K)) && !(is_load_to_a(first_inst)))
+       if (bpf_needs_clear_a(&ctx->skf->insns[0]))
                emit(ARM_MOV_I(r_A, 0), ctx);
 
        /* stack space for the BPF_MEM words */
@@ -770,7 +756,8 @@ load_ind:
                case BPF_ALU | BPF_RSH | BPF_K:
                        if (unlikely(k > 31))
                                return -1;
-                       emit(ARM_LSR_I(r_A, r_A, k), ctx);
+                       if (k)
+                               emit(ARM_LSR_I(r_A, r_A, k), ctx);
                        break;
                case BPF_ALU | BPF_RSH | BPF_X:
                        update_on_xread(ctx);