linux-kernel - Re: [PATCH 6/7] dynamic debug v2

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: <20080717214651.GC13252@redhat.com>
Date:	Thu, 17 Jul 2008 17:46:51 -0400
From:	Jason Baron <jbaron@...hat.com>
To:	Greg KH <greg@...ah.com>
Cc:	Dominik Brodowski <linux@...inikbrodowski.net>,
	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	joe@...ches.com, nick@...k-andrew.net, randy.dunlap@...cle.com
Subject: Re: [PATCH 6/7] dynamic debug v2 - convert cpufreq

On Thu, Jul 17, 2008 at 02:15:31PM -0700, Greg KH wrote:
> On Thu, Jul 17, 2008 at 05:05:32PM -0400, Jason Baron wrote:
> > --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
> > +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
> > @@ -25,6 +25,7 @@
> >   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >   */
> >  
> > +#include <linux/dynamic_debug_cpufreq.h>
> >  #include <linux/kernel.h>
> >  #include <linux/module.h>
> >  #include <linux/init.h>
> 
> kernel.h includes dynamic_debug.h right?  

yes

Then why not just put the
> _cpufreq.h stuff in the current cpufreq.h file(s)?
> 

1) cpufreq.h is included by other subsystems, and thus those other subsystems
potentially have the wrong debugging information.

2) For the case where CONFIG_CPU_FREQ_DEBUG is set and 
CONFIG_DYNAMIC_PRINTK_DEBUG is not set i need to be able get the proper
definition of 'dynamic_dbg_enabled()' out of dynamic_print.h (included by
kernel.h). This proper definition is obtained by setting 'DEBUG', and
thus i need to define this before the kernel.h include. 

We can solve #2 by defining an explicit definition for dynamic_dbg_enabled() 
when only CONFIG_CPU_FREQ_DEBUG within cpufreq.h. roughly:

#ifdef CONFIG_CPU_FREQ_DEBUG
#define cpufreq_debug_printk(flag) 
	if (cpufreq_debug & flag)
		 __cpufreq_debug_printk()

However, the way i have it now I don't need two definitions for 
cpufreq_debug_printk....

If we could pull the subsystem specific header in dynamic_printk.h for each 
subsytem that would do the trick and be really clean, but i'm not sure of an
easy way to do that...

-Jason

--
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/