lkml.org 
[lkml]   [2011]   [Sep]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Please revert "debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options"
On Fri, Sep 30, 2011 at 08:05:19AM -0700, Josh Triplett wrote:
> On Fri, Sep 30, 2011 at 04:42:45PM +0300, Adrian Bunk wrote:
>...
> > Let me point at the obvious fact that both CONFIG_DEBUG_BUGVERBOSE and
> > CONFIG_DEBUG_RODATA do depend on DEBUG_KERNEL, and are contrary to the
> > claim of the author of this patch never enabled with
> > CONFIG_DEBUG_KERNEL=n. [1]
>
> Not true:
>
> ~/src/linux-2.6$ rm .config
> ~/src/linux-2.6$ make allnoconfig
> HOSTCC scripts/basic/fixdep
> HOSTCC scripts/kconfig/conf.o
> HOSTCC scripts/kconfig/zconf.tab.o
> HOSTLD scripts/kconfig/conf
> scripts/kconfig/conf --allnoconfig Kconfig
> #
> # configuration written to .config
> #
> ~/src/linux-2.6$ grep BUGVERBOSE .config
> CONFIG_DEBUG_BUGVERBOSE=y
> ~/src/linux-2.6$ grep DEBUG_KERNEL .config
> # CONFIG_DEBUG_KERNEL is not set
>
> DEBUG_BUGVERBOSE does not depend on DEBUG_KERNEL; it just only shows up
> with DEBUG_KERNEL (and EXPERT) set. The *description* has a conditional
> on DEBUG_KERNEL and EXPERT:
>
> config DEBUG_BUGVERBOSE
> bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
>...

Apologies, I was wrong on DEBUG_BUGVERBOSE
(but for DEBUG_RODATA I was right).

>...
> Also see Ingo Molnar's mail with Message-Id
> <20110605093445.GA19927@elte.hu>, which explicitly recommended this
> approach.

Ingo is an expert in a gazillion areas of the kernel and knows more
about these than mere mortals like me will ever know.

Kconfig is (the?) one thing where he in not a good advisor.

Looking at the patch Frederic points at [1]:

config DEBUG_BUGVERBOSE
- bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+ bool "Verbose BUG() reporting (adds 70K)" if EXPERT

This part of the patch would have been the correct and complete
solution for DEBUG_BUGVERBOSE.

The crazy select added in commit f505c553 is wrong.

> - Josh Triplett

cu
Adrian

[1] http://lkml.org/lkml/2011/6/6/641

--

"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed



\
 
 \ /
  Last update: 2011-09-30 17:53    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site