From: Nathan Chancellor nathan@kernel.org
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 --- include/linux/mmdebug.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/mmdebug.h +++ b/include/linux/mmdebug.h @@ -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)) { \