linux-kernel - Re: [RESEND PATCH v5 3/5] drivers core: allow 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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <70b61b75-c68b-ad89-5f6a-f1d681b9f5d0@samsung.com>
Date:   Wed, 24 Jun 2020 21:39:57 +0200
From:   Andrzej Hajda <a.hajda@...sung.com>
To:     Robin Murphy <robin.murphy@....com>,
        Mark Brown <broonie@...nel.org>
Cc:     Jernej Skrabec <jernej.skrabec@...l.net>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Jonas Karlman <jonas@...boo.se>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "open list:DRM DRIVERS" <dri-devel@...ts.freedesktop.org>,
        Russell King - ARM Linux <linux@...linux.org.uk>,
        Neil Armstrong <narmstrong@...libre.com>,
        Andy Shevchenko <andy.shevchenko@...il.com>,
        Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
        Marek Szyprowski <m.szyprowski@...sung.com>,
        linux-arm Mailing List <linux-arm-kernel@...ts.infradead.org>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
Subject: Re: [RESEND PATCH v5 3/5] drivers core: allow probe_err accept
 integer and pointer types


On 24.06.2020 17:16, Robin Murphy wrote:
> On 2020-06-24 16:04, Mark Brown wrote:
>> On Wed, Jun 24, 2020 at 03:25:33PM +0100, Robin Murphy wrote:
>>
>>> And yeah, anyone who pipes up suggesting that places where an 
>>> ERR_PTR value
>>> could be passed to probe_err() could simply refactor IS_ERR() checks 
>>> with
>>> more uses of the god-awful PTR_ERR_OR_ZERO() obfuscator gets a long 
>>> stare of
>>> disapproval...
>>
>> We could also have a probe_err_ptr() or something that took an ERR_PTR()
>> instead if there really were an issue with explicitly doing this.
>
> Yeah, for all my lyrical objection, a static inline <blah>_ptr_err() 
> helper to wrap <blah>_err() with sensible type checking might actually 
> be an OK compromise if people really feel strongly for having that 
> utility.


I have proposed such thing in my previous iteration[1], except it was 
macro because of variadic arguments.

With current version we save 8 chars and hacky macro, with the old 
version we save only 4 chars and more clear construct - less tempting 
solution for me.

Personally I prefer the current version - it does not seems to me more 
dangerous than all these PTR_ERR, IS_ERR,ERR_PTR helpers, but can 
prevent expression split across  multiple lines due to 80char limit.

Probably the simplest solution is to drop this patch, I will do it then.

[1]: 
https://lwn.net/ml/linux-kernel/20181220102247.4911-4-a.hajda@samsung.com/


Regards

Andrzej


>
> (and then we can debate whether it should also convert NULL to -ENOMEM 
> and !IS_ERR to 0... :D)
>
> Robin.
> _______________________________________________
> dri-devel mailing list
> dri-devel@...ts.freedesktop.org
> https://protect2.fireeye.com/url?k=074420c0-5ada8e5a-0745ab8f-0cc47a336fae-bba8bb4caf96e14d&q=1&u=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fdri-devel 
>
>