linux-kernel - Re: [PATCH 1/1] Add documentation for proper usage and order of preference of calls to print diagnostic messages.

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]

Date:	Tue, 4 Mar 2014 15:50:33 +0100
From:	Levente Kurusa <levex@...ux.com>
To:	yogesh <mr.yogesh@...il.com>
Cc:	LKML <linux-kernel@...r.kernel.org>, Joe Perches <joe@...ches.com>,
	Rob Landley <rob@...dley.net>
Subject: Re: [PATCH 1/1] Add documentation for proper usage and order of
 preference of calls to print diagnostic messages.

Hi,

[+CC Rob]

2014-03-04 15:31 GMT+01:00 yogesh <mr.yogesh@...il.com>:
> This patch adds documentation that clarifies the use of various
> diagnostic printing messages. It shows the preference of subsystem_dbg
> calls to dev_dbg (whenever possible), as they first preferred format of
> logging debug messages.
> Signed-off-by: Yogesh Chaudhari <mr.yogesh@...il.com>

Acked-by: Levente Kurusa <levex@...ux.com>

> ---
>  Documentation/CodingStyle | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>
> diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle
> index 7fe0546..083f738 100644
> --- a/Documentation/CodingStyle
> +++ b/Documentation/CodingStyle
> @@ -662,6 +662,23 @@ and driver, and are tagged with the right level:  dev_err(), dev_warn(),
>  dev_info(), and so forth.  For messages that aren't associated with a
>  particular device, <linux/printk.h> defines pr_debug() and pr_info().
>
> +If the subsystem has its own diagnostic macros then they should be used
> +instead of dev_dbg calls.
> +e.g. If you are using network subsystem, use netdev_dbg;
> +if you are using V4L, use v4l_dbg etc.
> +This standardises the output format in every subsystem.
> +
> +Depending on your changes, the following order of precedence
> +applies to printing messages:
> +1. [subsystem]_dbg() is preferred when the subsystem has its own
> +diagnostic macros.
> +2. dev_dbg() is preferred when you have a generic struct device object.
> +3. pr_debug() should be used when 1 and 2 above are not applicable.
> +4. printk() should be avoided.
> +
> +Note: The above order applies to diagnostic calls of all log levels viz:
> +*_emerg, *_alert, *_crit, *_err, *_warn, *_notice, *_info and *_dbg.
> +
>  Coming up with good debugging messages can be quite a challenge; and once
>  you have them, they can be a huge help for remote troubleshooting.  Such
>  messages should be compiled out when the DEBUG symbol is not defined (that
> --
>
> Regards
> Yogesh
> [...]

A lot better, but please next time send it as a separate mail
with subject [PATCH v2] or something like that. Thanks!

--
Regards,
Levente Kurusa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/