Re: [2.6 patch] FW_LOADER should select HOTPLUG

[Adrian Bunk <bunk@stusta.de>]

On Sun, Dec 03, 2006 at 01:24:01AM -0800, Andrew Morton wrote:
> On Sun, 3 Dec 2006 09:15:52 +0100
> Adrian Bunk <bunk@stusta.de> wrote:
> 
> > On Sun, Dec 03, 2006 at 12:58:24AM -0800, Andrew Morton wrote:
> > > On Sun, 3 Dec 2006 08:16:37 +0100
> > > Adrian Bunk <bunk@stusta.de> wrote:
> > > 
> > > > Since FW_LOADER is an option that is always select'ed by the code using 
> > > > it, it mustn't depend on HOTPLUG.
> > > > 
> > > > It's only relevant in the EMBEDDED=y case, but this might have resulted 
> > > > in illegal FW_LOADER=, HOTPLUG=n configurations.
> > > > 
> > > > Signed-off-by: Adrian Bunk <bunk@stusta.de>
> > > > 
> > > > --- linux-2.6.19-rc6-mm2/drivers/base/Kconfig.old	2006-12-02 20:36:49.000000000 +0100
> > > > +++ linux-2.6.19-rc6-mm2/drivers/base/Kconfig	2006-12-02 20:37:03.000000000 +0100
> > > > @@ -19,8 +19,8 @@
> > > >  	  If unsure say Y here.
> > > >  
> > > >  config FW_LOADER
> > > > -	tristate "Userspace firmware loading support"
> > > > -	depends on HOTPLUG
> > > > +	tristate
> > > > +	select HOTPLUG
> > > 
> > > It would be a retrograde step to start selecting HOTPLUG - we've managed to
> > > avoid it thus far.
> > 
> > $ grep -r "select HOTPLUG" * | wc -l
> > 4
> > $ 
> > 
> > > It'd be better to make those drivers which select FW_LOADER dependent upon
> > > HOTPLUG.
> > 
> > $ grep -r "select FW_LOADER" * | wc -l
> > 71
> 
> 46 actually.  And it's immaterial.

Sorry, I had some .old and .orig files in my tree...

> > And since the only case where depends<->select makes a difference is 
> > CONFIG_EMBEDDED=y, people will always continue to forget the dependency 
> > on HOTPLUG when select'ing FW_LOADER.
> 
> I realise that.  But having HOTPLUG magically and mysteriously turn itself
> back on again is a pita.

In practice, it's already always turned on (except for CONFIG_EMBEDDED=n).

Unless Kconfig gets changed to automatically inherit dependencies of 
select'ed symbols, FW_LOADER not select'ing HOTPLUG is simply a constant 
source of bugs.

cu
Adrian

-- 

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