[tip: x86/core] objtool: Add --hacks=skylake

[tip-bot2 for Peter Zijlstra]

The following commit has been merged into the x86/core branch of tip:

Commit-ID:     0c0a6d8934e2081df93ba0bfc0cf615cc9c06988
Gitweb:        https://git.kernel.org/tip/0c0a6d8934e2081df93ba0bfc0cf615cc9c06988
Author:        Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate:    Thu, 15 Sep 2022 13:11:10 +02:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 17 Oct 2022 16:41:07 +02:00

objtool: Add --hacks=skylake

Make the call/func sections selectable via the --hacks option.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220915111146.120821440@xxxxxxxxxxxxx
---
 scripts/Makefile.lib                    |  1 +
 tools/objtool/builtin-check.c           |  7 ++++++-
 tools/objtool/check.c                   | 10 ++++++----
 tools/objtool/include/objtool/builtin.h |  1 +
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3aa384c..85f0275 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -254,6 +254,7 @@ objtool := $(objtree)/tools/objtool/objtool
 
 objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK)		+= --hacks=jump_label
 objtool-args-$(CONFIG_HAVE_NOINSTR_HACK)		+= --hacks=noinstr
+objtool-args-$(CONFIG_CALL_DEPTH_TRACKING)		+= --hacks=skylake
 objtool-args-$(CONFIG_X86_KERNEL_IBT)			+= --ibt
 objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL)	+= --mcount
 objtool-args-$(CONFIG_UNWINDER_ORC)			+= --orc
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index 24fbe80..0a04f8e 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -57,12 +57,17 @@ static int parse_hacks(const struct option *opt, const char *str, int unset)
 		found = true;
 	}
 
+	if (!str || strstr(str, "skylake")) {
+		opts.hack_skylake = true;
+		found = true;
+	}
+
 	return found ? 0 : -1;
 }
 
 const struct option check_options[] = {
 	OPT_GROUP("Actions:"),
-	OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label,noinstr", "patch toolchain bugs/limitations", parse_hacks),
+	OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label,noinstr,skylake", "patch toolchain bugs/limitations", parse_hacks),
 	OPT_BOOLEAN('i', "ibt", &opts.ibt, "validate and annotate IBT"),
 	OPT_BOOLEAN('m', "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"),
 	OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"),
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index f578e03..1461c88 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -4352,10 +4352,12 @@ int check(struct objtool_file *file)
 			goto out;
 		warnings += ret;
 
-		ret = create_direct_call_sections(file);
-		if (ret < 0)
-			goto out;
-		warnings += ret;
+		if (opts.hack_skylake) {
+			ret = create_direct_call_sections(file);
+			if (ret < 0)
+				goto out;
+			warnings += ret;
+		}
 	}
 
 	if (opts.mcount) {
diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h
index 42a52f1..22092a9 100644
--- a/tools/objtool/include/objtool/builtin.h
+++ b/tools/objtool/include/objtool/builtin.h
@@ -14,6 +14,7 @@ struct opts {
 	bool dump_orc;
 	bool hack_jump_label;
 	bool hack_noinstr;
+	bool hack_skylake;
 	bool ibt;
 	bool mcount;
 	bool noinstr;