diff options
| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2026-01-25 21:56:39 -0800 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@kernel.org> | 2026-01-27 08:20:47 -0800 |
| commit | f2dba60339a6299e181671e95293efe312237e2d (patch) | |
| tree | 930da55e368fd4d6a2a1176ff65dc24fe5f66c7c | |
| parent | d107b3265aa5e61a1e326b2815a767526ddb12ac (diff) | |
objtool/klp: Fix bug table handling for __WARN_printf()
Running objtool klp-diff on a changed function which uses WARN() can
fail with:
vmlinux.o: error: objtool: md_run+0x866: failed to convert reloc sym '__bug_table' to its proper format
The problem is that since commit 5b472b6e5bd9 ("x86_64/bug: Implement
__WARN_printf()"), each __WARN_printf() call site now directly
references its bug table entry. klp-diff errors out when it can't
convert such section-based references to object symbols (because bug
table entries don't have symbols).
Luckily, klp-diff already has code to create symbols for bug table
entries. Move that code earlier, before function diffing.
Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Fixes: 5b472b6e5bd9 ("x86_64/bug: Implement __WARN_printf()")
Reported-by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/a8e0a714b9da962858842b9aecd63b4900927c88.1769406850.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
| -rw-r--r-- | tools/objtool/klp-diff.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/tools/objtool/klp-diff.c b/tools/objtool/klp-diff.c index 4d1f9e9977eb..d94531e3f64e 100644 --- a/tools/objtool/klp-diff.c +++ b/tools/objtool/klp-diff.c @@ -1425,9 +1425,6 @@ static int clone_special_sections(struct elfs *e) { struct section *patched_sec; - if (create_fake_symbols(e->patched)) - return -1; - for_each_sec(e->patched, patched_sec) { if (is_special_section(patched_sec)) { if (clone_special_section(e, patched_sec)) @@ -1704,6 +1701,17 @@ int cmd_klp_diff(int argc, const char **argv) if (!e.out) return -1; + /* + * Special section fake symbols are needed so that individual special + * section entries can be extracted by clone_special_sections(). + * + * Note the fake symbols are also needed by clone_included_functions() + * because __WARN_printf() call sites add references to bug table + * entries in the calling functions. + */ + if (create_fake_symbols(e.patched)) + return -1; + if (clone_included_functions(&e)) return -1; |