Re: [PATCH] mmc: pwrseq_simple: Fix incorrect handling of GPIO bitmap

From: Linus Walleij
Date: Wed Sep 26 2018 - 03:50:33 EST


On Tue, Sep 25, 2018 at 9:23 PM Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx> wrote:

> Commit b9762bebc633 ("gpiolib: Pass bitmaps, not integer arrays, to
> get/set array") changed the way GPIO values are passed to
> gpiod_get/set_array_value() and friends. The updated code of
> mmc_pwrseq_simple_set_gpios_value() incorrectly uses the 'value'
> argument as a bitmap of GPIO values and assigns it directly to the
> 'values' bitmap variable passed to gpiod_set_array_value_cansleep()
> instead of filling that bitmap with bits equal to the 'value' argument.
> As a result, boot hanging caused by incorrectly handled MMC device
> has been observed.
>
> As a side effect of that incorrect interpreation of the 'value'
> argument, wrong assumption is taken about the 'values' bitmap size
> never exceding the number of bits of the 'value' argument type.
>
> Fix it.
>
> Reported-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx>

Nice!

Provided this works, Ulf can I have your ACK so I can queue this
with the rest of the gpio array rework in the GPIO tree?

Yours,
Linus Walleij