Re: [PATCH 0/2] Input: tests - miscellaneous fixes

[Geert Uytterhoeven]

Hi Dmitry,

On Tue, May 2, 2023 at 7:05 PM Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
> On Tue, May 02, 2023 at 06:31:51PM +0200, Javier Martinez Canillas wrote:
> > Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> writes:
> > > On Tue, May 2, 2023 at 12:17 PM Geert Uytterhoeven
> > > <geert+renesas@xxxxxxxxx> wrote:
> > >> This patch series fixes a crash in the new input selftest, and makes the
> > >> test available when the KUnit framework is modular.
> > >>
> > >> Unfortunately test 3 still fails for me (tested on Koelsch (R-Car M2-W)
> > >> and ARAnyM):
> > >>
> > >>         KTAP version 1
> > >>         # Subtest: input_core
> > >>         1..3
> > >>     input: Test input device as /devices/virtual/input/input1
> > >>         ok 1 input_test_polling
> > >>     input: Test input device as /devices/virtual/input/input2
> > >>         ok 2 input_test_timestamp
> > >>     input: Test input device as /devices/virtual/input/input3
> > >>         # input_test_match_device_id: ASSERTION FAILED at # drivers/input/tests/input_test.c:99
> > >>         Expected input_match_device_id(input_dev, &id) to be true, but is false
> > >>         not ok 3 input_test_match_device_id
> > >>     # input_core: pass:2 fail:1 skip:0 total:3
> > >>     # Totals: pass:2 fail:1 skip:0 total:3
> > >>     not ok 1 input_core
> > >
> > > Adding more debug code shows that it's the test on evbit [1] in
> > > input_match_device_id() that fails.
> > > Looking at your input_test_match_device_id(), I think you expect
> > > the checks for the various bitmaps to be gated by
> > > "if (id->flags & INPUT_DEVICE_ID_MATCH_EVBIT)", like is done for the
> > > other checks?
> > >
> > > [1] https://elixir.bootlin.com/linux/latest/source/drivers/input/input.c#L1021
> > >
> >
> > That's correct. In input_test_init(), the input dev is marked as capable
> > of emitting EV_KEY BTN_LEFT and BTN_RIGHT. The goal of that test was to
> > check this.
> >
> > That is, check if matches by the input dev capabilities in which case the
> > __set_bit(EV_KEY, ...) would make the match true and __set_bit(EV_ABS, ..)
> > would make the condition false.
> >
> > But maybe I misunderstood how the input_set_capability() and __set_bit()
> > functions work ?
> >
> > I'll take a look to this tomorrow, thanks a lot for your report!
>
> Unfortunately (?) INPUT_DEVICE_ID_MATCH_*BIT have never had any effect,
> the kernel always used bitmaps when matching (with the assumption that
> if one does not care about given bitmap they can simply pass empty one),
> so I think what we need to change is:
>
> diff --git a/drivers/input/tests/input_test.c b/drivers/input/tests/input_test.c
> index 8b8ac3412a70..0540225f0288 100644
> --- a/drivers/input/tests/input_test.c
> +++ b/drivers/input/tests/input_test.c
> @@ -87,7 +87,7 @@ static void input_test_timestamp(struct kunit *test)
>  static void input_test_match_device_id(struct kunit *test)
>  {
>         struct input_dev *input_dev = test->priv;
> -       struct input_device_id id;
> +       struct input_device_id id = { 0 };
>
>         /*
>          * Must match when the input device bus, vendor, product, version
>
> to avoid having garbage in the match data.

Thanks, that did the trick! 3/3 tests pass.


Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds