mars/pre-patches/vanilla-5.0/0001-objtool-Don-t-fail-on-...

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1.6 KiB
Diff

From 88ca7c5c9145d78f502b4fc2b5a21652f7b16c94 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Thu, 14 Jan 2021 16:14:01 -0600
Subject: [PATCH 1/4] 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>
---
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 c4857fa3f1d1..822df6e56d47 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -336,8 +336,11 @@ 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;
--
2.35.3