Re: [PATCH v2] selftests/bpf: Fix test_verifier after introducing resolve_pseudo_ldimm64

From: Hao Luo <haoluo@google.com>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Networking <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
	open list <linux-kernel@vger.kernel.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Andrii Nakryiko <andriin@fb.com>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>,
	John Fastabend <john.fastabend@gmail.com>,
	KP Singh <kpsingh@chromium.org>
Subject: Re: [PATCH v2] selftests/bpf: Fix test_verifier after introducing resolve_pseudo_ldimm64
Date: Tue, 6 Oct 2020 19:29:30 -0700	[thread overview]
Message-ID: <CA+khW7jYqFzEYoL4jEr3UX1PWGtNc-7i1HXhFMLu4EZCj2xB8g@mail.gmail.com> (raw)
In-Reply-To: <20201007020401.wsbeli3dbz7fumal@ast-mbp>

Ack. Sent one with just deletion.

Hao

On Tue, Oct 6, 2020 at 7:04 PM Alexei Starovoitov
<alexei.starovoitov@gmail.com> wrote:
>
> On Tue, Oct 06, 2020 at 06:23:13PM -0700, Hao Luo wrote:
> > Commit 4976b718c355 ("bpf: Introduce pseudo_btf_id") switched
> > the order of check_subprogs() and resolve_pseudo_ldimm() in
> > the verifier. Now an empty prog expects to see the error "last
> > insn is not an the prog of a single invalid ldimm exit or jmp"
> > instead, because the check for subprogs comes first. It's now
> > pointless to validate that half of ldimm64 won't be the last
> > instruction.
> >
> > Tested:
> >  # ./test_verifier
> >  Summary: 1129 PASSED, 537 SKIPPED, 0 FAILED
> >  and the full set of bpf selftests.
> >
> > Fixes: 4976b718c355 ("bpf: Introduce pseudo_btf_id")
> > Signed-off-by: Hao Luo <haoluo@google.com>
> > ---
> > Changelog in v2:
> >  - Remove the original test_verifier ld_imm64 test4
> >  - Updated commit message.
> >
> >  tools/testing/selftests/bpf/verifier/basic.c  |  2 +-
> >  .../testing/selftests/bpf/verifier/ld_imm64.c | 24 +++++++------------
> >  2 files changed, 9 insertions(+), 17 deletions(-)
> >
> > diff --git a/tools/testing/selftests/bpf/verifier/basic.c b/tools/testing/selftests/bpf/verifier/basic.c
> > index b8d18642653a..de84f0d57082 100644
> > --- a/tools/testing/selftests/bpf/verifier/basic.c
> > +++ b/tools/testing/selftests/bpf/verifier/basic.c
> > @@ -2,7 +2,7 @@
> >       "empty prog",
> >       .insns = {
> >       },
> > -     .errstr = "unknown opcode 00",
> > +     .errstr = "last insn is not an exit or jmp",
> >       .result = REJECT,
> >  },
> >  {
> > diff --git a/tools/testing/selftests/bpf/verifier/ld_imm64.c b/tools/testing/selftests/bpf/verifier/ld_imm64.c
> > index 3856dba733e9..ed6a34991216 100644
> > --- a/tools/testing/selftests/bpf/verifier/ld_imm64.c
> > +++ b/tools/testing/selftests/bpf/verifier/ld_imm64.c
> > @@ -54,21 +54,13 @@
> >       "test5 ld_imm64",
> >       .insns = {
> >       BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, 0, 0, 0, 0),
> > -     },
> > -     .errstr = "invalid bpf_ld_imm64 insn",
> > -     .result = REJECT,
> > -},
> > -{
> > -     "test6 ld_imm64",
> > -     .insns = {
> > -     BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, 0, 0, 0, 0),
> >       BPF_RAW_INSN(0, 0, 0, 0, 0),
> >       BPF_EXIT_INSN(),
> >       },
> >       .result = ACCEPT,
> >  },
> >  {
> > -     "test7 ld_imm64",
> > +     "test6 ld_imm64",
> >       .insns = {
> >       BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, 0, 0, 0, 1),
> >       BPF_RAW_INSN(0, 0, 0, 0, 1),
> > @@ -78,7 +70,7 @@
> >       .retval = 1,
> >  },
> >  {
> > -     "test8 ld_imm64",
> > +     "test7 ld_imm64",
>
> imo that's too much churn to rename all of them.
> Just delete one.