Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.31 as permitted sender) client-ip=23.128.96.31;
MIME-Version: 1.0
References: <20231212131031.3088661-1-menglong8.dong@gmail.com>
 <20231212131031.3088661-3-menglong8.dong@gmail.com> <8a9d03eb74918123615cc3579cefc484566cad5d.camel@gmail.com>
In-Reply-To: <8a9d03eb74918123615cc3579cefc484566cad5d.camel@gmail.com>
From:   Menglong Dong <menglong8.dong@gmail.com>
Date:   Wed, 13 Dec 2023 10:35:53 +0800
Message-ID: <CADxym3a58ALYnJH5HdVZEfgBUeKH3+mH9mHGf6SijxCOzFjD3g@mail.gmail.com>
Subject: Re: [PATCH net-next v2 2/2] selftests/bpf: activate the OP_NE login
 in range_cond()
To:     Eduard Zingerman <eddyz87@gmail.com>
Cc:     andrii@kernel.org, yonghong.song@linux.dev, ast@kernel.org,
        daniel@iogearbox.net, john.fastabend@gmail.com,
        martin.lau@linux.dev, song@kernel.org, kpsingh@kernel.org,
        sdf@google.com, haoluo@google.com, jolsa@kernel.org,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

Hello,

On Wed, Dec 13, 2023 at 7:37=E2=80=AFAM Eduard Zingerman <eddyz87@gmail.com=
> wrote:
>
> On Tue, 2023-12-12 at 21:10 +0800, Menglong Dong wrote:
> > The edge range checking for the registers is supported by the verifier
> > now, so we can activate the extended login in
> > tools/testing/selftests/bpf/prog_tests/reg_bounds.c/range_cond() to tes=
t
> > such logic.
> >
> > Signed-off-by: Menglong Dong <menglong8.dong@gmail.com>
> > ---
> >  tools/testing/selftests/bpf/prog_tests/reg_bounds.c | 7 +------
> >  1 file changed, 1 insertion(+), 6 deletions(-)
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/reg_bounds.c b/tool=
s/testing/selftests/bpf/prog_tests/reg_bounds.c
> > index 0c9abd279e18..49d8d4bafe99 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/reg_bounds.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/reg_bounds.c
> > @@ -590,12 +590,7 @@ static void range_cond(enum num_t t, struct range =
x, struct range y,
> >               *newy =3D range(t, max_t(t, x.a, y.a), min_t(t, x.b, y.b)=
);
> >               break;
> >       case OP_NE:
> > -             /* generic case, can't derive more information */
> > -             *newx =3D range(t, x.a, x.b);
> > -             *newy =3D range(t, y.a, y.b);
> > -             break;
> > -
> > -             /* below extended logic is not supported by verifier just=
 yet */
> > +             /* below logic is supported by the verifier now */
> >               if (x.a =3D=3D x.b && x.a =3D=3D y.a) {
> >                       /* X is a constant matching left side of Y */
> >                       *newx =3D range(t, x.a, x.b);
>
> I think that some crafted tests have to be added.
> Note that reg_bounds only runs a subset of tests during CI
> (controlled by variable SLOW_TESTS).
> By default only randomized and crafted tests are run.
> It appears to me that probability of randomly generating specific
> ranges explored by this series is quite low.

You are right, I'll add some cases to the "crafted_cases" for
this logic.

Thanks!
Menglong Dong