linux-kernel - Re: [PATCH v2] gpiolib: Show correct direction from the beginning

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CACRpkdaN5G4ephY+6BPLRF+aUrO4-sPa+2erRYrwTGwPBwu8fw@mail.gmail.com>
Date:   Mon, 1 Oct 2018 23:20:21 +0200
From:   Linus Walleij <linus.walleij@...aro.org>
To:     Ricardo Ribalda Delgado <ricardo.ribalda@...il.com>
Cc:     timur@...nel.org, jhugo@...eaurora.org,
        Stephen Boyd <swboyd@...omium.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>
Subject: Re: [PATCH v2] gpiolib: Show correct direction from the beginning

On Mon, Oct 1, 2018 at 3:36 PM Ricardo Ribalda Delgado
<ricardo.ribalda@...il.com> wrote:
> On Mon, Oct 1, 2018 at 1:54 PM Linus Walleij <linus.walleij@...aro.org> wrote:
> > On Fri, Sep 28, 2018 at 9:30 PM Ricardo Ribalda Delgado
> > <ricardo.ribalda@...il.com> wrote:
> >
> > > How do we proceed from here? Can you fix your driver somehow to
> > > init the valid mask before enabling the gpio?
> >
> > Just include a hunk to the qcom driver reordering this call
> > at the same time. No need to make it separate patches,
> > it need to be tested together anyways.
> >
> > I guess just switch the order of these two:
> >
> >         ret = gpiochip_add_data(&pctrl->chip, pctrl);
> >         if (ret) {
> >                 dev_err(pctrl->dev, "Failed register gpiochip\n");
> >                 return ret;
> >         }
> >
> >         ret = msm_gpio_init_valid_mask(chip, pctrl);
> >         if (ret) {
> >                 dev_err(pctrl->dev, "Failed to setup irq valid bits\n");
> >                 gpiochip_remove(&pctrl->chip);
> >                 return ret;
> >         }
> >
>
> the problem is that valid_mask is not a long/integer, is a struct that
> needs to be malloced, and is malloc at gpiochip_add_data :(

I don't get it, but maybe I'm not smart enough.

gpiochip_add_data() doesn't allocate anything, it
just adds a already allocated (or static!) gpio_chip
to the gpiolib subsystem.

In fact I think it is wrong to set up the mask after
calling gpiolob_add_data(), because of exactly the
type of problem you're seeing.

Don't get confused by the &pctrl->chip
vs just chip variables, it's just some sloppiness.

Yours,
Linus Walleij