linux-kernel - Re: [PATCH v2] driver: core: Allow subsystems to continue deferring probe

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 for Android: free password hash cracker in your pocket

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

Date:   Fri, 14 Jun 2019 12:10:10 +0200
From:   "Rafael J. Wysocki" <rafael@...nel.org>
To:     Thierry Reding <thierry.reding@...il.com>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J . Wysocki" <rafael@...nel.org>,
        Kevin Hilman <khilman@...nel.org>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        Joerg Roedel <joro@...tes.org>,
        Linus Walleij <linus.walleij@...aro.org>,
        Rob Herring <robh@...nel.org>,
        Linux PM <linux-pm@...r.kernel.org>,
        linux-gpio@...r.kernel.org,
        "open list:AMD IOMMU (AMD-VI)" <iommu@...ts.linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2] driver: core: Allow subsystems to continue deferring probe

On Fri, Jun 14, 2019 at 11:39 AM Thierry Reding
<thierry.reding@...il.com> wrote:
>
> On Fri, Jun 14, 2019 at 11:10:58AM +0200, Greg Kroah-Hartman wrote:
> > On Thu, Jun 13, 2019 at 07:00:11PM +0200, Thierry Reding wrote:
> > > From: Thierry Reding <treding@...dia.com>
> > >

[cut]

>
> To avoid further back and forth, what exactly is it that you would have
> me do? That is, what do you consider to be the correct way to do this?
>
> Would you prefer me to add another function with a different name that
> reimplements the functionality only with the exception? Something along
> the lines of:
>
>         int driver_deferred_probe_check_state_continue(struct device *dev)
>         {
>                 int ret;
>
>                 ret = driver_deferred_probe_check_state(dev);
>                 if (ret == -ENODEV)
>                         return -EPROBE_DEFER;
>
>                 return ret;
>         }
>
> ? I'd need to split that up some more to avoid the warning that the
> inner function prints before returning -ENODEV, but that's a minor
> detail. Would that API be more to your liking?

Well, why don't you do

static int deferred_probe_check_state_internal(struct device *dev)
{
        if (!initcalls_done)
                return -EPROBE_DEFER;

        if (!deferred_probe_timeout) {
                dev_WARN(dev, "deferred probe timeout, ignoring dependency");
                return -ETIMEDOUT;
        }

        return 0;
}

int driver_deferred_probe_check_state(struct device *dev)
{
        int ret = deferred_probe_check_state_internal(dev);

        if (ret)
                 return ret;

        dev_warn(dev, "ignoring dependency for device, assuming no driver");
        return -ENODEV;
}

int driver_deferred_probe_check_state_continue(struct device *dev)
{
        int ret = deferred_probe_check_state_internal(dev);

        if (ret)
                 return ret;

        return -EPROBE_DEFER;
}