From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@roeck-us.net (Guenter Roeck)
Date: Thu, 21 Aug 2014 19:19:47 -0700
Subject: [PATCH v7 04/11] arm: Support restart through restart handler
 call chain
In-Reply-To: <53F69DBA.4070806@suse.de>
References: <1408495538-27480-1-git-send-email-linux@roeck-us.net>
 <1408495538-27480-5-git-send-email-linux@roeck-us.net>
 <53F69DBA.4070806@suse.de>
Message-ID: <20140822021947.GA17788@roeck-us.net>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, Aug 22, 2014 at 03:32:42AM +0200, Andreas F?rber wrote:
> Hi,
> 
> Am 20.08.2014 02:45, schrieb Guenter Roeck:
> > The kernel core now supports a restart handler call chain for system
> > restart functions.
> > 
> > With this change, the arm_pm_restart callback is now optional, so
> > drop its initialization and check if it is set before calling it.
> > Only call the kernel restart handler if arm_pm_restart is not set.
> [...]
> > diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
> > index 81ef686..ea279f7 100644
> > --- a/arch/arm/kernel/process.c
> > +++ b/arch/arm/kernel/process.c
> > @@ -114,17 +114,13 @@ void soft_restart(unsigned long addr)
> >  	BUG();
> >  }
> >  
> > -static void null_restart(enum reboot_mode reboot_mode, const char *cmd)
> > -{
> > -}
> > -
> >  /*
> >   * Function pointers to optional machine specific functions
> >   */
> >  void (*pm_power_off)(void);
> >  EXPORT_SYMBOL(pm_power_off);
> >  
> > -void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd) = null_restart;
> > +void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
> 
> Stupid newbie question maybe, but isn't this variable uninitialized now,
> like any non-static variable in C99? Or does the kernel assure that all
> such "fields" are zero-initialized?
> 
It is initialized with NULL, like all other global and static variables in the
kernel (and like pm_power_off a few lines above).

Guenter