[PATCH] arm64: lds: move .got section out of .text

From: Fangrui Song
Date: Fri Apr 28 2023 - 01:05:11 EST


Currently, the .got section is placed within the output section .text.
However, when .got is non-empty, the SHF_WRITE flag is set when linked
by lld. GNU ld recognizes .text as a special section and ignores the
SHF_WRITE flag. By renaming .text, we can also get the SHF_WRITE flag.

Conventionally, the .got section is placed just before .got.plt (which
should be empty and omitted in the kernel). Therefore, we move the .got
section to a conventional location (between .text and .data) and remove
the unneeded `. = ALIGN(16)`.

Signed-off-by: Fangrui Song <maskray@xxxxxxxxxx>
---
arch/arm64/kernel/vmlinux.lds.S | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index b9202c2ee18e..2bcb3b30db41 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -181,18 +181,8 @@ SECTIONS
KPROBES_TEXT
HYPERVISOR_TEXT
*(.gnu.warning)
- . = ALIGN(16);
- *(.got) /* Global offset table */
}

- /*
- * Make sure that the .got.plt is either completely empty or it
- * contains only the lazy dispatch entries.
- */
- .got.plt : { *(.got.plt) }
- ASSERT(SIZEOF(.got.plt) == 0 || SIZEOF(.got.plt) == 0x18,
- "Unexpected GOT/PLT entries detected!")
-
. = ALIGN(SEGMENT_ALIGN);
_etext = .; /* End of text section */

@@ -247,6 +237,16 @@ SECTIONS

. = ALIGN(SEGMENT_ALIGN);
__inittext_end = .;
+
+ .got : { *(.got) }
+ /*
+ * Make sure that the .got.plt is either completely empty or it
+ * contains only the lazy dispatch entries.
+ */
+ .got.plt : { *(.got.plt) }
+ ASSERT(SIZEOF(.got.plt) == 0 || SIZEOF(.got.plt) == 0x18,
+ "Unexpected GOT/PLT entries detected!")
+
__initdata_begin = .;

init_idmap_pg_dir = .;
--
2.40.1.495.gc816e09b53d-goog