From: Masahiro Yamada masahiroy@kernel.org
commit 99cb0d917ffa1ab628bb67364ca9b162c07699b1 upstream.
Dennis Gilmore reports that the BuildID is missing in the arm64 vmlinux since commit 994b7ac1697b ("arm64: remove special treatment for the link order of head.o").
The issue is that the type of .notes section, which contains the BuildID, changed from NOTES to PROGBITS.
Ard Biesheuvel figured out that whichever object gets linked first gets to decide the type of a section. The PROGBITS type is the result of the compiler emitting .note.GNU-stack as PROGBITS rather than NOTE.
While Ard provided a fix for arm64, I want to fix this globally because the same issue is happening on riscv since commit 2348e6bf4421 ("riscv: remove special treatment for the link order of head.o"). This problem will happen in general for other architectures if they start to drop unneeded entries from scripts/head-object-list.txt.
Discard .note.GNU-stack in include/asm-generic/vmlinux.lds.h.
Link: https://lore.kernel.org/lkml/CAABkxwuQoz1CTbyb57n0ZX65eSYiTonFCU8-LCQc=74D=x... Fixes: 994b7ac1697b ("arm64: remove special treatment for the link order of head.o") Fixes: 2348e6bf4421 ("riscv: remove special treatment for the link order of head.o") Reported-by: Dennis Gilmore dennis@ausil.us Suggested-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Masahiro Yamada masahiroy@kernel.org Acked-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Tom Saeger tom.saeger@oracle.com --- include/asm-generic/vmlinux.lds.h | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index d233f9e4b9c6..44103f9487c9 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -906,7 +906,12 @@ #define TRACEDATA #endif
+/* + * Discard .note.GNU-stack, which is emitted as PROGBITS by the compiler. + * Otherwise, the type of .notes section would become PROGBITS instead of NOTES. + */ #define NOTES \ + /DISCARD/ : { *(.note.GNU-stack) } \ .notes : AT(ADDR(.notes) - LOAD_OFFSET) { \ __start_notes = .; \ KEEP(*(.note.*)) \