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Subject: Re: [patch 2/2] x86_64: align RODATA kernel section to 2MB with
 CONFIG_DEBUG_RODATA
From: Suresh Siddha <suresh.b.siddha@intel.com>
Reply-To: Suresh Siddha <suresh.b.siddha@intel.com>
To: Sam Ravnborg <sam@ravnborg.org>
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       "arjan@linux.jf.intel.com" <arjan@linux.jf.intel.com>,
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       "Ma, Chinang" <chinang.ma@intel.com>
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Organization: Intel Corp
Date: Thu, 15 Oct 2009 13:23:48 -0700
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On Wed, 2009-10-14 at 20:24 -0700, Sam Ravnborg wrote:
> > +#else
> > +
> > +#define X64_ALIGN_DEBUG_RODATA_BEGIN
> > +#define X64_ALIGN_DEBUG_RODATA_END
> > +
> > +#endif
> 
> A coment describing the purpose of
> this would be nice.

I will update this in the next version of the patch.

> > @@ -726,9 +726,13 @@ void set_kernel_text_ro(void)
> >  
> >  void mark_rodata_ro(void)
> >  {
> > -	unsigned long start = PFN_ALIGN(_text), end = PFN_ALIGN(__end_rodata);
> > +	unsigned long start = PFN_ALIGN(_text);
> >  	unsigned long rodata_start =
> >  		((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
> > +	unsigned long end = (unsigned long) &__end_rodata_hpage_align;
> Here the symbol seems to be referenced unconditionally.

This function is defined only for CONFIG_DEBUG_RODATA.

thanks,
suresh