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| author | Andrii Nakryiko <andrii@kernel.org> | 2023-11-18 06:46:21 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-11-18 22:39:59 +0300 |
| commit | 1db747d75b1dbe17bf4283ed87bd3b7a92010f34 (patch) | |
| tree | d266e1595982f440d336448b39d0a3c26974ea6a /kernel/bpf/log.c | |
| parent | 0c95c9fdb696f35c7864785ba84cb9a50152daff (diff) | |
| download | linux-1db747d75b1dbe17bf4283ed87bd3b7a92010f34.tar.xz | |
bpf: omit default off=0 and imm=0 in register state log
Simplify BPF verifier log further by omitting default (and frequently
irrelevant) off=0 and imm=0 parts for non-SCALAR_VALUE registers. As can
be seen from fixed tests, this is often a visual noise for PTR_TO_CTX
register and even for PTR_TO_PACKET registers.
Omitting default values follows the rest of register state logic: we
omit default values to keep verifier log succinct and to highlight
interesting state that deviates from default one. E.g., we do the same
for var_off, when it's unknown, which gives no additional information.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231118034623.3320920-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf/log.c')
| -rw-r--r-- | kernel/bpf/log.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/kernel/bpf/log.c b/kernel/bpf/log.c index c209ab1ec2b5..20b4f81087da 100644 --- a/kernel/bpf/log.c +++ b/kernel/bpf/log.c @@ -602,16 +602,14 @@ static void print_reg_state(struct bpf_verifier_env *env, const struct bpf_reg_s reg->map_ptr->key_size, reg->map_ptr->value_size); } - if (t != SCALAR_VALUE) + if (t != SCALAR_VALUE && reg->off) verbose_a("off=%d", reg->off); if (type_is_pkt_pointer(t)) verbose_a("r=%d", reg->range); if (tnum_is_const(reg->var_off)) { - /* Typically an immediate SCALAR_VALUE, but - * could be a pointer whose offset is too big - * for reg->off - */ - verbose_a("imm=%llx", reg->var_off.value); + /* a pointer register with fixed offset */ + if (reg->var_off.value) + verbose_a("imm=%llx", reg->var_off.value); } else { print_scalar_ranges(env, reg, &sep); if (!tnum_is_unknown(reg->var_off)) { |