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mm: Fix '.data.once' orphan section warning

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Portions of upstream commit a4055888629b ("mm/memcg: warning on !memcg
after readahead page charged") were backported as commit cfe575954ddd
("mm: add VM_WARN_ON_ONCE_PAGE() macro"). Unfortunately, the backport
did not account for the lack of commit 33def8498fdd ("treewide: Convert
macro and uses of __section(foo) to __section("foo")") in kernels prior
to 5.10, resulting in the following orphan section warnings on PowerPC
clang builds with CONFIG_DEBUG_VM=y:

  powerpc64le-linux-gnu-ld: warning: orphan section `".data.once"' from `mm/huge_memory.o' being placed in section `".data.once"'
  powerpc64le-linux-gnu-ld: warning: orphan section `".data.once"' from `mm/huge_memory.o' being placed in section `".data.once"'
  powerpc64le-linux-gnu-ld: warning: orphan section `".data.once"' from `mm/huge_memory.o' being placed in section `".data.once"'

This is a difference between how clang and gcc handle macro
stringification, which was resolved for the kernel by not stringifying
the argument to the __section() macro. Since that change was deemed not
suitable for the stable kernels by commit 59f89518f510 ("once: fix
section mismatch on clang builds"), do that same thing as that change
and remove the quotes from the argument to __section().

Fixes: cfe575954ddd ("mm: add VM_WARN_ON_ONCE_PAGE() macro")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Nathan Chancellor 2022-11-28 15:53:46 -07:00 committed by Greg Kroah-Hartman
parent c9ecc42094
commit ced17a55a8
1 changed files with 1 additions and 1 deletions
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2
include/linux/mmdebug.h
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@ -38,7 +38,7 @@ void dump_mm(const struct mm_struct *mm);
} \
} while (0)
#define VM_WARN_ON_ONCE_PAGE(cond, page) ({ \
static bool __section(".data.once") __warned; \
static bool __section(.data.once) __warned; \
int __ret_warn_once = !!(cond); \
\
if (unlikely(__ret_warn_once && !__warned)) { \