vmlinux.lds.h: Allow architectures to add sections to the front of .bss

Follow-on MIPS patch will put an object here that needs 64K alignment
to minimize padding.

For those architectures that don't define BSS_FIRST_SECTIONS, there is
no change.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org,
Cc: linux-kernel@vger.kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Patchwork: https://patchwork.linux-mips.org/patch/4221/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 4e2e1cc505ab..d1ea7ce0b4cb 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -530,9 +530,18 @@
                 *(.scommon)                                             \
         }
 
+/*
+ * Allow archectures to redefine BSS_FIRST_SECTIONS to add extra
+ * sections to the front of bss.
+ */
+#ifndef BSS_FIRST_SECTIONS
+#define BSS_FIRST_SECTIONS
+#endif
+
 #define BSS(bss_align)                                                  \
         . = ALIGN(bss_align);                                           \
         .bss : AT(ADDR(.bss) - LOAD_OFFSET) {                           \
+                BSS_FIRST_SECTIONS                                      \
                 *(.bss..page_aligned)                                   \
                 *(.dynbss)                                              \
                 *(.bss)                                                 \