From ca0f4fe7cf7183bfbdc67ca2de56ae1fc3a8db2b Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <nathan@kernel.org>
Date: Thu, 6 Feb 2025 10:21:38 -0700
Subject: [PATCH] arm64: Handle .ARM.attributes section in linker scripts

A recent LLVM commit [1] started generating an .ARM.attributes section
similar to the one that exists for 32-bit, which results in orphan
section warnings (or errors if CONFIG_WERROR is enabled) from the linker
because it is not handled in the arm64 linker scripts.

  ld.lld: error: arch/arm64/kernel/vdso/vgettimeofday.o:(.ARM.attributes) is being placed in '.ARM.attributes'
  ld.lld: error: arch/arm64/kernel/vdso/vgetrandom.o:(.ARM.attributes) is being placed in '.ARM.attributes'

  ld.lld: error: vmlinux.a(lib/vsprintf.o):(.ARM.attributes) is being placed in '.ARM.attributes'
  ld.lld: error: vmlinux.a(lib/win_minmax.o):(.ARM.attributes) is being placed in '.ARM.attributes'
  ld.lld: error: vmlinux.a(lib/xarray.o):(.ARM.attributes) is being placed in '.ARM.attributes'

Discard the new sections in the necessary linker scripts to resolve the
warnings, as the kernel and vDSO do not need to retain it, similar to
the .note.gnu.property section.

Cc: stable@vger.kernel.org
Fixes: b3e5d80d0c48 ("arm64/build: Warn on orphan section placement")
Link: https://github.com/llvm/llvm-project/commit/ee99c4d4845db66c4daa2373352133f4b237c942 [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250206-arm64-handle-arm-attributes-in-linker-script-v3-1-d53d169913eb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kernel/vdso/vdso.lds.S | 1 +
 arch/arm64/kernel/vmlinux.lds.S   | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/arm64/kernel/vdso/vdso.lds.S b/arch/arm64/kernel/vdso/vdso.lds.S
index 4ec32e86a8da..47ad6944f9f0 100644
--- a/arch/arm64/kernel/vdso/vdso.lds.S
+++ b/arch/arm64/kernel/vdso/vdso.lds.S
@@ -41,6 +41,7 @@ SECTIONS
 	 */
 	/DISCARD/	: {
 		*(.note.GNU-stack .note.gnu.property)
+		*(.ARM.attributes)
 	}
 	.note		: { *(.note.*) }		:text	:note
 
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index f84c71f04d9e..e73326bd3ff7 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -162,6 +162,7 @@ SECTIONS
 	/DISCARD/ : {
 		*(.interp .dynamic)
 		*(.dynsym .dynstr .hash .gnu.hash)
+		*(.ARM.attributes)
 	}
 
 	. = KIMAGE_VADDR;