linux-kernel - Re: [PATCH 2/2] driver core: fix statics initilisation

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: <CAJZ5v0gj1p0KNUZkZ3JG2ppK1706GSfY3J12mDNx-E75Y_J3Cg@mail.gmail.com>
Date:   Tue, 16 Apr 2019 10:50:23 +0200
From:   "Rafael J. Wysocki" <rafael@...nel.org>
To:     Willy Wolff <willy.mh.wolff.ml@...il.com>
Cc:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] driver core: fix statics initilisation

On Mon, Apr 15, 2019 at 5:29 PM Willy Wolff <willy.mh.wolff.ml@...il.com> wrote:
>
> Thank you for your review.
>
> I follow https://kernelnewbies.org/FirstKernelPatch to write this patch.
> It's not stated that checkpatch.pl is for new patches only. Moreover,
> https://kernelnewbies.org/FirstKernelPatch#Running_checkpatch.pl suggest to
> run over the entire file.

I'm not sure about the source of that recommendation.

In any case, running it over the entire file doesn't mean that you
should or even need to make all of the warnings in that file go away.

> Also, uninitialised static global variable are initialised to 0 by default.
> Thus, initialising driver_deferred_probe_enable to false (which is 0) is
> redundant.

Yes, it is redundant, but it also is harmless AFAICS.

> As my knowledge, initialised global goes to .data section, and uninitialised
> goes to .bss.
>
> What does it mean for the kernel? Is this still hold?

No, I don't think so.

> Are performance or memory footprint of the kernel be affected?

No, they aren't.

The only difference this makes is the removal of redundant
initialization to 0, which may be regarded as a cleanup, but not as a
fix IMO.

If that's the only reason you have to change the file in question,
doing something else instead of that may be a better allocation of
your time.

Thanks!