Josh Poimboeuf 37ffdca816 objtool: Support Clang non-section symbols in ORC generation ... commit e81e072443 upstream. When compiling the kernel with AS=clang, objtool produces a lot of warnings: warning: objtool: missing symbol for section .text warning: objtool: missing symbol for section .init.text warning: objtool: missing symbol for section .ref.text It then fails to generate the ORC table. The problem is that objtool assumes text section symbols always exist. But the Clang assembler is aggressive about removing them. When generating relocations for the ORC table, objtool always tries to reference instructions by their section symbol offset. If the section symbol doesn't exist, it bails. Do a fallback: when a section symbol isn't available, reference a function symbol instead. Reported-by: Dmitry Golovin <dima@golovin.in> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://github.com/ClangBuiltLinux/linux/issues/669 Link: https://lkml.kernel.org/r/9a9cae7fcf628843aabe5a086b1a3c5bf50f42e8.1585761021.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-02-10 09:12:08 +01:00
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arch/x86	x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytes	2020-12-11 13:39:07 +01:00
Documentation
.gitignore	objtool: Move synced files to their original relative locations	2017-12-29 17:53:41 +01:00
arch.h
Build
builtin-check.c	objtool: Add module specific retpoline rules	2018-03-15 10:54:38 +01:00
builtin-orc.c	objtool: Use existing global variables for options	2018-03-15 10:54:37 +01:00
builtin.h	objtool: Add module specific retpoline rules	2018-03-15 10:54:38 +01:00
cfi.h
check.c	objtool: Fix noreturn detection for ignored functions	2020-10-01 13:12:49 +02:00
check.h	objtool: Support per-function rodata sections	2019-06-25 11:36:50 +08:00
elf.c	objtool: Don't fail on missing symbol table	2021-02-07 14:47:41 +01:00
elf.h	objtool: Support per-function rodata sections	2019-06-25 11:36:50 +08:00
Makefile	objtool: Clobber user CFLAGS variable	2019-10-05 12:47:35 +02:00
objtool.c
orc.h	objtool: Move synced files to their original relative locations	2017-12-29 17:53:41 +01:00
orc_dump.c	objtool: Support Clang non-section symbols in ORC dump	2020-05-02 17:24:44 +02:00
orc_gen.c	objtool: Support Clang non-section symbols in ORC generation	2021-02-10 09:12:08 +01:00
special.c
special.h
sync-check.sh	objtool: Move kernel headers/code sync check to a script	2017-12-29 17:53:42 +01:00
warn.h