linux-kernel - Re: [PATCH v1 1/2] driver core: Introduce device_find_first

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: <CAJZ5v0ge=W+GZx2zzHBg4_su1OqSQ9DOovR4RmoU1KJocDqwOw@mail.gmail.com>
Date:   Wed, 8 Jun 2022 14:19:15 +0200
From:   "Rafael J. Wysocki" <rafael@...nel.org>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Cc:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Mark Brown <broonie@...nel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-spi <linux-spi@...r.kernel.org>
Subject: Re: [PATCH v1 1/2] driver core: Introduce device_find_first_child() helper

On Wed, Jun 8, 2022 at 1:54 PM Andy Shevchenko
<andriy.shevchenko@...ux.intel.com> wrote:
>
> On Wed, Jun 08, 2022 at 01:29:08PM +0200, Rafael J. Wysocki wrote:
> > On Tue, Jun 7, 2022 at 10:22 PM Andy Shevchenko
> > <andriy.shevchenko@...ux.intel.com> wrote:
>
> ...
>
> > I would define it as
> >
> > static int match_first(struct device *dev, void *)
> > {
> >        return 1;
> > }
> >
> > struct device *device_find_first_child(struct device *parent)
> > {
> >         return device_find_first_child(parent, NULL, match_first);
> > }
> > EXPORT_SYMBOL_GPL(device_find_first_child);
> >
> > which is not that much more overhead.
>
> With this we actually may simply provide a match function and it will make the
> clean ups (like patch 2 in the series) almost the same without introducing a
> device core call.

That works too, but IMO it would be a bit cleaner to have the wrapper
defined as a proper function.

>
> Something like
>
> int device_match_any_for_find(struct device *dev, void *unused)
> {
>         return 1;
> }
>
> As I replied to Greg it's pity we can't use device_match_any()...

Well, that only is a matter of adding one more variant of _match_any_ ...