[PATCH 3/3] powerpc/mm: Mark __init memory no-execute when STRICT_KERNEL_RWX=y

[Michael Ellerman]

kbuild test robot <lkp at intel.com> writes:

> Hi Michael,
>
> [auto build test ERROR on powerpc/next]
> [also build test ERROR on next-20170714]
> [cannot apply to v4.12]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url:    https://github.com/0day-ci/linux/commits/Michael-Ellerman/powerpc-mm-radix-Refactor-radix__mark_rodata_ro/20170715-043340
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
> config: powerpc-allnoconfig (attached as .config)
> compiler: powerpc-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
> reproduce:
>         wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         make.cross ARCH=powerpc 
>
> All errors (new ones prefixed by >>):
>
>    arch/powerpc/mm/mem.c: In function 'free_initmem':
>>> arch/powerpc/mm/mem.c:413:2: error: implicit declaration of function 'mark_initmem_nx' [-Werror=implicit-function-declaration]
>      mark_initmem_nx();
>      ^~~~~~~~~~~~~~~
>    cc1: all warnings being treated as errors

Gah, 32-bit.

Fixed with:

diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 3d562b210c65..d1da415e283c 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -1193,11 +1193,5 @@ static inline const int pud_pfn(pud_t pud)
 	return 0;
 }
 
-#ifdef CONFIG_STRICT_KERNEL_RWX
-void mark_initmem_nx(void);
-#else
-static inline void mark_initmem_nx(void) { }
-#endif
-
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_POWERPC_BOOK3S_64_PGTABLE_H_ */
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index dd01212935ac..afae9a336136 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -80,6 +80,13 @@ unsigned long vmalloc_to_phys(void *vmalloc_addr);
 
 void pgtable_cache_add(unsigned shift, void (*ctor)(void *));
 void pgtable_cache_init(void);
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+void mark_initmem_nx(void);
+#else
+static inline void mark_initmem_nx(void) { }
+#endif
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_POWERPC_PGTABLE_H */