With NUMA=n and FA_DUMP=y or PRESERVE_FA_DUMP=y the build fails with:
arch/powerpc/kernel/fadump.c:1739:22: error: no previous prototype for ‘arch_reserved_kernel_pages’ [-Werror=missing-prototypes]
1739 | unsigned long __init arch_reserved_kernel_pages(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
The prototype for arch_reserved_kernel_pages() is in include/linux/mm.h,
but it's guarded by __HAVE_ARCH_RESERVED_KERNEL_PAGES. The powerpc
headers define __HAVE_ARCH_RESERVED_KERNEL_PAGES in asm/mmzone.h, which
is not included into the generic headers when NUMA=n.
Move the definition of __HAVE_ARCH_RESERVED_KERNEL_PAGES into asm/mmu.h
which is included regardless of NUMA=n.
Additionally the ifdef around __HAVE_ARCH_RESERVED_KERNEL_PAGES needs to
also check for CONFIG_PRESERVE_FA_DUMP.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231130114433.3053544-1-mpe@ellerman.id.au
#include <asm/nohash/mmu.h>
#endif
+#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)
+#define __HAVE_ARCH_RESERVED_KERNEL_PAGES
+#endif
+
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_MMU_H_ */
#else
#define memory_hotplug_max() memblock_end_of_DRAM()
#endif /* CONFIG_NUMA */
-#ifdef CONFIG_FA_DUMP
-#define __HAVE_ARCH_RESERVED_KERNEL_PAGES
-#endif
#endif /* __KERNEL__ */
#endif /* _ASM_MMZONE_H_ */