[PATCH 6.3] riscv: vmlinux.lds.S: Explicitly handle '.got' section

Nathan Chancellor
2023-06-05T21:15:28Z

This patch is for linux-6.3.y only, it has no direct mainline
equivalent.

LLVM 17 will now use the GOT for extern weak symbols when using the
medany model, which causes a linker orphan section warning on
linux-6.3.y:

ld.lld: warning: <internal>:(.got) is being placed in '.got'

This is not an issue in mainline because handling of the .got section
was added by commit 39b33072941f ("riscv: Introduce CONFIG_RELOCATABLE")
and further extended by commit 26e7aacb83df ("riscv: Allow to downgrade
paging mode from the command line") in 6.4-rc1. Neither of these changes
are suitable for stable, so add explicit handling of the .got section in
a standalone change to align 6.3 and mainline, which addresses the
warning.

This is only an issue for 6.3 because commit f4b71bff8d85 ("riscv:
select ARCH_WANT_LD_ORPHAN_WARN for !XIP_KERNEL") landed in 6.3-rc1, so
earlier releases will not see this warning because it will not be
enabled.

Closes: https://github.com/ClangBuiltLinux/linux/issues/1865
Link: https://github.com/llvm/llvm-project/commit/a178ba9fbd0a27057dc2fa4cb53c76caa013caac
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
arch/riscv/kernel/vmlinux.lds.S | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S
index 53a8ad65b255..db56c38f0e19 100644
--- a/arch/riscv/kernel/vmlinux.lds.S
+++ b/arch/riscv/kernel/vmlinux.lds.S
@@ -129,6 +129,8 @@ SECTIONS
*(.sdata*)
}

+ .got : { *(.got*) }
+
#ifdef CONFIG_EFI
.pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); }
__pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end);

---
base-commit: abfd9cf1c3d4d143a889b76af835078897e46c55
change-id: 20230605-6-3-riscv-got-orphan-warning-llvm-17-8c4b0b72282a

Best regards,
--
Nathan Chancellor <nathan@kernel.org>