arch: fix broken BuildID for arm64 and riscv
authorMasahiro Yamada <masahiroy@kernel.org>
Mon, 26 Dec 2022 18:45:37 +0000 (03:45 +0900)
committerMasahiro Yamada <masahiroy@kernel.org>
Fri, 30 Dec 2022 08:21:51 +0000 (17:21 +0900)
commit99cb0d917ffa1ab628bb67364ca9b162c07699b1
tree3d7f72e2a3b5f7b2250ad8fd38a4d398ab362ff8
parentda8daff9405e55baa1f797b77a7c629a89f4d764
arch: fix broken BuildID for arm64 and riscv

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=xE=rA@mail.gmail.com/
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>
include/asm-generic/vmlinux.lds.h