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Date: Sun, 5 Jun 2011 11:38:07 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Sam Ravnborg <sam@ravnborg.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Unhide DEBUG_RODATA if EXPERT, even if DEBUG_KERNEL=n
Message-ID: <20110605093807.GB19927@elte.hu>
References: <20110605083739.GA18560@leaf>
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* Josh Triplett <josh@joshtriplett.org> wrote:

> --- a/arch/x86/Kconfig.debug
> +++ b/arch/x86/Kconfig.debug
> @@ -81,7 +81,7 @@ config X86_PTDUMP
>  config DEBUG_RODATA
>  	bool "Write protect kernel read-only data structures"
>  	default y
> -	depends on DEBUG_KERNEL
> +	depends on DEBUG_KERNEL || EXPERT

This is doing it the wrong way around. The right solution is what i 
wrote for verbose-debug: if we select DEBUG_KERNEL from EXPERT then 
you will avoid having to expand || EXPERT conditions into every 
default-enabled debug facility ...

My suggested solution will be a lot easier to maintain as well as 
under your scheme, because with your scheme we'd have to:

  - add || EXPERT every time a debug facility is enabled by default

  - remove || EXPERT every time a debug facility is switched to 
    off-by-default

If EXPERT selects DEBUG_KERNEL then we always get the right behavior, 
without polluting debug Kconfig's with EXPERT logic ...


Thanks,

	Ingo