From 9e2308c133a92ff98d1397149c8483858bcf8fc0 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:24 -0700 Subject: [PATCH] tools: bpftool: print all relevant byte opcodes for "load double word" The eBPF instruction permitting to load double words (8 bytes) into a register need 8-byte long "immediate" field, and thus occupy twice the space of other instructions. bpftool was aware of this and would increment the instruction counter only once on meeting such instruction, but it would only print the first four bytes of the immediate value to load. Make it able to dump the whole 16 byte-long double instruction instead (as would `llvm-objdump -d `). Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/prog.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 355c14325622..57edbea2fbe8 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -313,20 +313,29 @@ static void print_insn(struct bpf_verifier_env *env, const char *fmt, ...) static void dump_xlated(void *buf, unsigned int len, bool opcodes) { struct bpf_insn *insn = buf; + bool double_insn = false; unsigned int i; for (i = 0; i < len / sizeof(*insn); i++) { + if (double_insn) { + double_insn = false; + continue; + } + + double_insn = insn[i].code == (BPF_LD | BPF_IMM | BPF_DW); + printf("% 4d: ", i); print_bpf_insn(print_insn, NULL, insn + i, true); if (opcodes) { printf(" "); fprint_hex(stdout, insn + i, 8, " "); + if (double_insn && i < len - 1) { + printf(" "); + fprint_hex(stdout, insn + i + 1, 8, " "); + } printf("\n"); } - - if (insn[i].code == (BPF_LD | BPF_IMM | BPF_DW)) - i++; } } -- 2.30.2