[PATCH 6.1 006/219] powerpc/mm: Fix build failures due to arch_reserved_kernel_pages()

Greg Kroah-Hartman
2024-02-03T04:08:41Z

From: Michael Ellerman <mpe@ellerman.id.au>

[ Upstream commit d8c3f243d4db24675b653f0568bb65dae34e6455 ]

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
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/include/asm/mmu.h | 4 ++++
arch/powerpc/include/asm/mmzone.h | 3 ---
2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index 94b981152667..07fabb054aea 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -417,5 +417,9 @@ extern void *abatron_pteptrs[2];
#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_ */
diff --git a/arch/powerpc/include/asm/mmzone.h b/arch/powerpc/include/asm/mmzone.h
index 4c6c6dbd182f..3764d3585d30 100644
--- a/arch/powerpc/include/asm/mmzone.h
+++ b/arch/powerpc/include/asm/mmzone.h
@@ -42,9 +42,6 @@ u64 memory_hotplug_max(void);
#else
#define memory_hotplug_max() memblock_end_of_DRAM()
#endif /* CONFIG_NUMA */
-#ifdef CONFIG_FA_DUMP
-#define __HAVE_ARCH_RESERVED_KERNEL_PAGES
-#endif

#ifdef CONFIG_MEMORY_HOTPLUG
extern int create_section_mapping(unsigned long start, unsigned long end,
--
2.43.0