Commit 52b4c58b authored Jan 14, 2021 by Josh Poimboeuf Committed by Greg Kroah-Hartman Feb 07, 2021

objtool: Don't fail on missing symbol table



[ Upstream commit 1d489151e9f9d1647110277ff77282fe4d96d09b ]

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@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1254


Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 10365001

tools/objtool/elf.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -226,8 +226,11 @@ 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;
		}

		symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;