[PATCH] powerpc/mm: Fix section mismatch warning in stop_machine_change_mapping()

Fix the warning messages for stop_machine_change_mapping(), and a number
of other affected functions in its call chain.

All modified functions are under CONFIG_MEMORY_HOTPLUG, so __meminit
is okay (keeps them / does not discard them).

Boot-tested on powernv/power9/radix-mmu and pseries/power8/hash-mmu.

    $ make -j$(nproc) CONFIG_DEBUG_SECTION_MISMATCH=y vmlinux
    ...
      MODPOST vmlinux.o
    WARNING: vmlinux.o(.text+0x6b130): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit 
    annotation or the annotation of create_physical_mapping is wrong.

    WARNING: vmlinux.o(.text+0x6b13c): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit 
    annotation or the annotation of create_physical_mapping is wrong.
    ...

Signed-off-by: Mauricio Faria de Oliveira <redacted>
---
 arch/powerpc/mm/mem.c              |  4 ++--
 arch/powerpc/mm/pgtable-book3s64.c |  4 ++--
 arch/powerpc/mm/pgtable-radix.c    | 12 ++++++------
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c611..85245ef 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c

@@ -127,7 +127,7 @@ int __weak remove_section_mapping(unsigned long start, unsigned long end)
 	return -ENODEV;
 }
 
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+int __meminit arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 		bool want_memblock)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;

@@ -148,7 +148,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int __meminit arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;

diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c
index 422e802..bd6ca74 100644
--- a/arch/powerpc/mm/pgtable-book3s64.c
+++ b/arch/powerpc/mm/pgtable-book3s64.c

@@ -155,7 +155,7 @@ void mmu_cleanup_all(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int create_section_mapping(unsigned long start, unsigned long end)
+int __meminit create_section_mapping(unsigned long start, unsigned long end)
 {
 	if (radix_enabled())
 		return radix__create_section_mapping(start, end);

@@ -163,7 +163,7 @@ int create_section_mapping(unsigned long start, unsigned long end)
 	return hash__create_section_mapping(start, end);
 }
 
-int remove_section_mapping(unsigned long start, unsigned long end)
+int __meminit remove_section_mapping(unsigned long start, unsigned long end)
 {
 	if (radix_enabled())
 		return radix__remove_section_mapping(start, end);

diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index 2e10a96..ab9db0a 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c

@@ -695,7 +695,7 @@ struct change_mapping_params {
 	unsigned long aligned_end;
 };
 
-static int stop_machine_change_mapping(void *data)
+static int __meminit stop_machine_change_mapping(void *data)
 {
 	struct change_mapping_params *params =
 			(struct change_mapping_params *)data;

@@ -742,7 +742,7 @@ static void remove_pte_table(pte_t *pte_start, unsigned long addr,
 /*
  * clear the pte and potentially split the mapping helper
  */
-static void split_kernel_mapping(unsigned long addr, unsigned long end,
+static void __meminit split_kernel_mapping(unsigned long addr, unsigned long end,
 				unsigned long size, pte_t *pte)
 {
 	unsigned long mask = ~(size - 1);

@@ -835,7 +835,7 @@ static void remove_pud_table(pud_t *pud_start, unsigned long addr,
 	}
 }
 
-static void remove_pagetable(unsigned long start, unsigned long end)
+static void __meminit remove_pagetable(unsigned long start, unsigned long end)
 {
 	unsigned long addr, next;
 	pud_t *pud_base;

@@ -863,12 +863,12 @@ static void remove_pagetable(unsigned long start, unsigned long end)
 	radix__flush_tlb_kernel_range(start, end);
 }
 
-int __ref radix__create_section_mapping(unsigned long start, unsigned long end)
+int __meminit radix__create_section_mapping(unsigned long start, unsigned long end)
 {
 	return create_physical_mapping(start, end);
 }
 
-int radix__remove_section_mapping(unsigned long start, unsigned long end)
+int __meminit radix__remove_section_mapping(unsigned long start, unsigned long end)
 {
 	remove_pagetable(start, end);
 	return 0;

@@ -888,7 +888,7 @@ int __meminit radix__vmemmap_create_mapping(unsigned long start,
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-void radix__vmemmap_remove_mapping(unsigned long start, unsigned long page_size)
+void __meminit radix__vmemmap_remove_mapping(unsigned long start, unsigned long page_size)
 {
 	remove_pagetable(start, start + page_size);
 }

-- 
1.8.3.1

On Sat, Mar 10, 2018 at 7:45 AM, Mauricio Faria de Oliveira
[off-list ref] wrote:

Fix the warning messages for stop_machine_change_mapping(), and a number
of other affected functions in its call chain.

All modified functions are under CONFIG_MEMORY_HOTPLUG, so __meminit
is okay (keeps them / does not discard them).

Boot-tested on powernv/power9/radix-mmu and pseries/power8/hash-mmu.

    $ make -j$(nproc) CONFIG_DEBUG_SECTION_MISMATCH=y vmlinux
    ...
      MODPOST vmlinux.o
    WARNING: vmlinux.o(.text+0x6b130): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit
    annotation or the annotation of create_physical_mapping is wrong.

    WARNING: vmlinux.o(.text+0x6b13c): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit
    annotation or the annotation of create_physical_mapping is wrong.
    ...

Signed-off-by: Mauricio Faria de Oliveira <redacted>
---

Looks reasonable, I'd recommend trying to compile with MEMORY_HOTPLUG
and MEMORY_HOTREMOVE enabled/disabled as well

Acked-by: Balbir Singh <bsingharora@gmail.com>

Balbir Singh.

Balbir,

On 03/11/2018 03:23 AM, Balbir Singh wrote:

Looks reasonable, I'd recommend trying to compile with MEMORY_HOTPLUG
and MEMORY_HOTREMOVE enabled/disabled as well

Thanks for reviewing.

I should have mentioned it :) I did that (disable CONFIG_MEMORY_HOTPLUG)
and all the related functions are not included in vmlinux, since they
are guarded under that config option.

cheers,
Mauricio

On Fri, 2018-03-09 at 20:45:58 UTC, Mauricio Faria de Oliveira wrote:

Fix the warning messages for stop_machine_change_mapping(), and a number
of other affected functions in its call chain.

All modified functions are under CONFIG_MEMORY_HOTPLUG, so __meminit
is okay (keeps them / does not discard them).

Boot-tested on powernv/power9/radix-mmu and pseries/power8/hash-mmu.

    $ make -j$(nproc) CONFIG_DEBUG_SECTION_MISMATCH=y vmlinux
    ...
      MODPOST vmlinux.o
    WARNING: vmlinux.o(.text+0x6b130): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit 
    annotation or the annotation of create_physical_mapping is wrong.

    WARNING: vmlinux.o(.text+0x6b13c): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit 
    annotation or the annotation of create_physical_mapping is wrong.
    ...

Signed-off-by: Mauricio Faria de Oliveira <redacted>
Acked-by: Balbir Singh <bsingharora@gmail.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/bde709a70884bfc790da6fbc4467c9

cheers