The following commit has been merged into the objtool/urgent branch of tip:
Commit-ID: 1d489151e9f9d1647110277ff77282fe4d96d09b
Gitweb: https://git.kernel.org/tip/1d489151e9f9d1647110277ff77282fe4d96d09b
Author: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
AuthorDate: Thu, 14 Jan 2021 16:14:01 -06:00
Committer: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
CommitterDate: Thu, 21 Jan 2021 15:49:58 -06:00
objtool: Don't fail on missing symbol table
Thanks to a recent binutils change which doesn't generate unused
symbols, it's now possible for thunk_64.o be completely empty without
CONFIG_PREEMPTION: no text, no data, no symbols.
We could edit the Makefile to only build that file when
CONFIG_PREEMPTION is enabled, but that will likely create confusion
if/when the thunks end up getting used by some other code again.
Just ignore it and move on.
Reported-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Reviewed-by: Miroslav Benes <mbenes@xxxxxxx>
Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/1254
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
tools/objtool/elf.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index f9682db..d8421e1 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -380,8 +380,11 @@ static int read_symbols(struct elf *elf)
symtab = find_section_by_name(elf, ".symtab");
if (!symtab) {
- WARN("missing symbol table");
- return -1;
+ /*
+ * A missing symbol table is actually possible if it's an empty
+ * .o file. This can happen for thunk_64.o.
+ */
+ return 0;
}
symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
|