The following commit has been merged into the x86/core branch of tip:
Commit-ID: 68a59124f4c6363de619fea63231a97dd220a12c
Gitweb: https://git.kernel.org/tip/68a59124f4c6363de619fea63231a97dd220a12c
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Fri, 26 Mar 2021 16:12:14 +01:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Thu, 01 Apr 2021 13:29:40 +02:00
objtool: Skip magical retpoline .altinstr_replacement
When the .altinstr_replacement is a retpoline, skip the alternative.
We already special case retpolines anyway.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Miroslav Benes <mbenes@xxxxxxx>
Link: https://lkml.kernel.org/r/20210326151300.259429287@xxxxxxxxxxxxx
---
tools/objtool/special.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/tools/objtool/special.c b/tools/objtool/special.c
index 2c7fbda..07b21cf 100644
--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -106,6 +106,14 @@ static int get_alt_entry(struct elf *elf, struct special_entry *entry,
return -1;
}
+ /*
+ * Skip retpoline .altinstr_replacement... we already rewrite the
+ * instructions for retpolines anyway, see arch_is_retpoline()
+ * usage in add_{call,jump}_destinations().
+ */
+ if (arch_is_retpoline(new_reloc->sym))
+ return 1;
+
alt->new_sec = new_reloc->sym->sec;
alt->new_off = (unsigned int)new_reloc->addend;
@@ -154,7 +162,9 @@ int special_get_alts(struct elf *elf, struct list_head *alts)
memset(alt, 0, sizeof(*alt));
ret = get_alt_entry(elf, entry, sec, idx, alt);
- if (ret)
+ if (ret > 0)
+ continue;
+ if (ret < 0)
return ret;
list_add_tail(&alt->list, alts);
|