2019-10-30 15:19:11

by Ilya Leoshkevich

[permalink] [raw]
Subject: [PATCH v2] mm/sparse.c: mark populate_section_memmap as __meminit

Building the kernel on s390 with -Og produces the following warning:

WARNING: vmlinux.o(.text+0x28dabe): Section mismatch in reference from the function populate_section_memmap() to the function .meminit.text:__populate_section_memmap()
The function populate_section_memmap() references
the function __meminit __populate_section_memmap().
This is often because populate_section_memmap lacks a __meminit
annotation or the annotation of __populate_section_memmap is wrong.

While -Og is not supported, in theory this might still happen with
another compiler or on another architecture. So fix this by using the
correct section annotations.

Signed-off-by: Ilya Leoshkevich <[email protected]>
---

v1 -> v2: Do not touch mm/sparse.c version of __populate_section_memmap:
its __init annotation is correct, since it is only called during init
phase (by sparse_init_nid), and contains the call to another __init
function. Spotted by kbuild test robot <[email protected]> and Oscar
Salvador <[email protected]>.

I was notified that v1 has already been included into
http://ozlabs.org/~akpm/mmots/broken-out. Since this is not a git
repository, I've decided to send a v2 instead of the fix. Please let me
know if I should send a fix instead.

mm/sparse.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/sparse.c b/mm/sparse.c
index f6891c1992b1..c2c01b6330af 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -647,7 +647,7 @@ void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
#endif

#ifdef CONFIG_SPARSEMEM_VMEMMAP
-static struct page *populate_section_memmap(unsigned long pfn,
+static struct page * __meminit populate_section_memmap(unsigned long pfn,
unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
{
return __populate_section_memmap(pfn, nr_pages, nid, altmap);
@@ -669,7 +669,7 @@ static void free_map_bootmem(struct page *memmap)
vmemmap_free(start, end, NULL);
}
#else
-struct page *populate_section_memmap(unsigned long pfn,
+struct page * __meminit populate_section_memmap(unsigned long pfn,
unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
{
struct page *page, *ret;
--
2.23.0


2019-10-30 15:35:09

by David Hildenbrand

[permalink] [raw]
Subject: Re: [PATCH v2] mm/sparse.c: mark populate_section_memmap as __meminit

On 30.10.19 16:16, Ilya Leoshkevich wrote:
> Building the kernel on s390 with -Og produces the following warning:
>
> WARNING: vmlinux.o(.text+0x28dabe): Section mismatch in reference from the function populate_section_memmap() to the function .meminit.text:__populate_section_memmap()
> The function populate_section_memmap() references
> the function __meminit __populate_section_memmap().
> This is often because populate_section_memmap lacks a __meminit
> annotation or the annotation of __populate_section_memmap is wrong.
>
> While -Og is not supported, in theory this might still happen with
> another compiler or on another architecture. So fix this by using the
> correct section annotations.
>
> Signed-off-by: Ilya Leoshkevich <[email protected]>
> ---
>
> v1 -> v2: Do not touch mm/sparse.c version of __populate_section_memmap:
> its __init annotation is correct, since it is only called during init
> phase (by sparse_init_nid), and contains the call to another __init
> function. Spotted by kbuild test robot <[email protected]> and Oscar
> Salvador <[email protected]>.
>
> I was notified that v1 has already been included into
> http://ozlabs.org/~akpm/mmots/broken-out. Since this is not a git
> repository, I've decided to send a v2 instead of the fix. Please let me
> know if I should send a fix instead.

That's fine, Andrew will simply replace the patch.

Acked-by: David Hildenbrand <[email protected]>

--

Thanks,

David / dhildenb