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From:   Marco Elver <elver@google.com>
Date:   Sun, 16 Oct 2022 22:08:24 -0700
Message-ID: <CANpmjNO0hu7OHmckU7kAVu+C6Jy_M_yMxe41YmcF2oePxh7Rnw@mail.gmail.com>
Subject: Re: [PATCH] kcsan: remove rng selftest
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     dvyukov@google.com, kasan-dev@googlegroups.com,
        linux-kernel@vger.kernel.org
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On Sun, 16 Oct 2022 at 22:07, Marco Elver <elver@google.com> wrote:
>
> On Sun, 16 Oct 2022 at 21:43, Jason A. Donenfeld <Jason@zx2c4.com> wrote:
> >
> > The first test of the kcsan selftest appears to test if get_random_u32()
> > returns two zeros in a row, and requires that it doesn't. This seems
> > like a bogus critera. Remove it.
> >
> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
>
> Acked-by: Marco Elver <elver@google.com>
>
> Looks pretty redundant at this point (I think some early version had
> it because somehow I managed to run the test too early and wanted to
> avoid that accidentally happening again).
>

And kindly queue it in your tree with all the rng related changes. Thanks!

> > ---
> >  kernel/kcsan/selftest.c | 8 --------
> >  1 file changed, 8 deletions(-)
> >
> > diff --git a/kernel/kcsan/selftest.c b/kernel/kcsan/selftest.c
> > index 00cdf8fa5693..1740ce389e7f 100644
> > --- a/kernel/kcsan/selftest.c
> > +++ b/kernel/kcsan/selftest.c
> > @@ -22,13 +22,6 @@
> >
> >  #define ITERS_PER_TEST 2000
> >
> > -/* Test requirements. */
> > -static bool __init test_requires(void)
> > -{
> > -       /* random should be initialized for the below tests */
> > -       return get_random_u32() + get_random_u32() != 0;
> > -}
> > -
> >  /*
> >   * Test watchpoint encode and decode: check that encoding some access's info,
> >   * and then subsequent decode preserves the access's info.
> > @@ -259,7 +252,6 @@ static int __init kcsan_selftest(void)
> >                         pr_err("selftest: " #do_test " failed");               \
> >         } while (0)
> >
> > -       RUN_TEST(test_requires);
> >         RUN_TEST(test_encode_decode);
> >         RUN_TEST(test_matching_access);
> >         RUN_TEST(test_barrier);
> > --
> > 2.37.3
> >