Received-SPF: pass (google.com: domain of linux-kernel+bounces-89682-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Precedence: bulk
MIME-Version: 1.0
References: <20240227113426.253232-1-herve.codina@bootlin.com>
 <CAMRc=MeSMTnPUYGyJir4fc=6=Gnw_MVP9wfEKMQ6Ck33FYCrRA@mail.gmail.com>
 <CACRpkdZbGUd-u3ZcmmK1POSEq8z9J1aDhbGPAbcR6guKuEpEFQ@mail.gmail.com>
 <CAMRc=MeqiYZv3ViHRKKUsXTqG5Pc8Ev2jUcN=A4VuX3RU7dDtw@mail.gmail.com>
 <CACRpkdYWDzu+VMQOYO_Sh1NM2ei=VRC-0df4teAZjirfrTB67A@mail.gmail.com> <CAMRc=MdLmU3uezKSg2d83HSZ3wYXFx68oGshx_yJyvJToN261Q@mail.gmail.com>
In-Reply-To: <CAMRc=MdLmU3uezKSg2d83HSZ3wYXFx68oGshx_yJyvJToN261Q@mail.gmail.com>
From: Linus Walleij <linus.walleij@linaro.org>
Date: Sun, 3 Mar 2024 09:48:00 +0100
Message-ID: <CACRpkdaQ5OthgFMG+6DNy7BGi+qLMgqNMOfk+cqra37EGyEYRA@mail.gmail.com>
Subject: Re: [PATCH v2 0/2] gpio-cdev: Release IRQ used by gpio-cdev on gpio
 chip removal
To: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Herve Codina <herve.codina@bootlin.com>, Kent Gibson <warthog618@gmail.com>, 
	Saravana Kannan <saravanak@google.com>, linux-gpio@vger.kernel.org, 
	linux-kernel@vger.kernel.org, Luca Ceresoli <luca.ceresoli@bootlin.com>, 
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Sat, Mar 2, 2024 at 10:00=E2=80=AFAM Bartosz Golaszewski <brgl@bgdev.pl>=
 wrote:
> On Fri, Mar 1, 2024 at 9:15=E2=80=AFPM Linus Walleij <linus.walleij@linar=
o.org> wrote:

> > The problem is that I have never heard about a user unbinding/binding
> > a driver from sysfs for anything but debugging a drivers ability to
> > bind/unbind. Partly I feel that thing should just be moved
> > to debugfs given the usecase and because it just looks like a way for
> > attackers to provoke crashes given how some drivers look.
>
> That's not the only thing - device unbind can also be triggered by
> removing the module providing the driver which is a completely normal
> operation for user-space.

That is one thing, but every time I hear about "have you thought about
users going in and using bind/unbind in sysfs" it's for builtin bool
drivers.

I almost feel like bool drivers should have bind/unbind disabled by
default :/

The introduction of deferred probe has made the situation much better
because it tends to exercise the bind/unbind path a bit.

Yours,
Linus Walleij