summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorTor Vic <torvic9@mailbox.org>2021-06-10 20:58:06 +0000
committerKees Cook <keescook@chromium.org>2021-06-11 10:33:45 -0700
commit2398ce80152aae33b9501ef54452e09e8e8d4262 (patch)
tree60111bfca3f0cf97cdad8393c542528d8b3106fd
parent06af8679449d4ed282df13191fc52d5ba28ec536 (diff)
downloadlinux-2398ce80152aae33b9501ef54452e09e8e8d4262.tar.bz2
x86, lto: Pass -stack-alignment only on LLD < 13.0.0
Since LLVM commit 3787ee4, the '-stack-alignment' flag has been dropped [1], leading to the following error message when building a LTO kernel with Clang-13 and LLD-13: ld.lld: error: -plugin-opt=-: ld.lld: Unknown command line argument '-stack-alignment=8'. Try 'ld.lld --help' ld.lld: Did you mean '--stackrealign=8'? It also appears that the '-code-model' flag is not necessary anymore starting with LLVM-9 [2]. Drop '-code-model' and make '-stack-alignment' conditional on LLD < 13.0.0. These flags were necessary because these flags were not encoded in the IR properly, so the link would restart optimizations without them. Now there are properly encoded in the IR, and these flags exposing implementation details are no longer necessary. [1] https://reviews.llvm.org/D103048 [2] https://reviews.llvm.org/D52322 Cc: stable@vger.kernel.org Link: https://github.com/ClangBuiltLinux/linux/issues/1377 Signed-off-by: Tor Vic <torvic9@mailbox.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/f2c018ee-5999-741e-58d4-e482d5246067@mailbox.org
-rw-r--r--arch/x86/Makefile5
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 307529417021..cb5e8d39cac1 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -200,8 +200,9 @@ endif
KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE)
ifdef CONFIG_LTO_CLANG
-KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \
- -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8)
+ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
+KBUILD_LDFLAGS += -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8)
+endif
endif
ifdef CONFIG_X86_NEED_RELOCS