Hi Nathan,
On Tue, Feb 04, 2025 at 10:48:55AM -0700, Nathan Chancellor wrote:
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/ee99c4d4845db66c4daa2373352133f4... [1] Signed-off-by: Nathan Chancellor nathan@kernel.org
Changes in v2:
- Discard the section instead of adding it to the final artifacts to mirror the .note.gnu.property section handling (Will).
Thanks for the v2. Just a minor nit:
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..8095fef66209 100644 --- a/arch/arm64/kernel/vdso/vdso.lds.S +++ b/arch/arm64/kernel/vdso/vdso.lds.S @@ -80,6 +80,7 @@ SECTIONS *(.data .data.* .gnu.linkonce.d.* .sdata*) *(.bss .sbss .dynbss .dynsbss) *(.eh_frame .eh_frame_hdr)
*(.ARM.attributes)
Can we chuck this in the earlier /DISCARD/ section along with .note.gnu.property? i.e.
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
Will