Hi,
while investigating following section mismatch warning:

WARNING: arch/x86/mm/built-in.o(.text+0xf2): Section mismatch in reference from the function paravirt_pagetable_setup_start() to the function

 .init.text:native_pagetable_setup_start()
I have found something with looks quite strange for me. This section mismatch is really easy to fix, as paravirt_pagetable_setup_start() is used by __init pagetable_init().

paravirt_pagetable_setup_start() (body in include/asm-x86/pgtable_32.h) calls, #ifndef CONFIG_PARAVIRT, __init native_pagetable_setup_start(). Here everything is OK and case is clear: to fix that mismatch, we need to annotate paravirt_pagetable_setup_start() with __init.
Same situation applies to paravirt_pagetable_setup_done(), but here it calls __init native_pagetable_setup_done(). On the other hand native_pagetable_setup_done() is quite strange:

void __init native_pagetable_setup_done(pgd_t *base)

{

}
This ,,change'' was introduced by commit: 551889a6e2a24a9c06fd453ea03b57b7746ffdc0 (x86: construct 32-bit boot time page tables in native format.), diff:

 void __init native_pagetable_setup_done(pgd_t *base)

 {

-#ifdef CONFIG_X86_PAE

-       /*

-        * Add low memory identity-mappings - SMP needs it when

-        * starting up on an AP from real-mode. In the non-PAE

-        * case we already have these mappings through head.S.

-        * All user-space mappings are explicitly cleared after

-        * SMP startup.

-        */

-       set_pgd(&base[0], base[USER_PTRS_PER_PGD]);

-#endif

 }
native_pagetable_setup_done() is used in __init pagetable_init() through paravirt_pagetable_setup_done(), nothing really scary.

One can take a look at arch/x86/kernel/paravirt.c:

struct pv_mmu_ops pv_mmu_ops = {

#ifndef CONFIG_X86_64

        .pagetable_setup_start = native_pagetable_setup_start,

        .pagetable_setup_done = native_pagetable_setup_done,

#endif

So when paravirt_pagetable_setup_done() will be called while CONFIG_PARAVIRT set it will be exactly same funct...
[ message continues ]

while generally it's nice to add 'extern' to prototypes, it's not an

outright bug to not have it. Also, __init is a must-have in the

definition only - it should not be added to the prototype.
	Ingo

--

Sounds reasonably. Sorry for calling something crap. When I slept well it looks fine and clear for me.
-Jacek

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