From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 19 Sep 2017 02:43:30 +0000 (-0500)
Subject: objtool: Don't report end of section error after an empty unwind hint
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=42314edefac8a80efb3d00a9f83bf1b1871bd473;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

objtool: Don't report end of section error after an empty unwind hint

commit 00d96180dc38ef872ac471c2d3e14b067cbd895d upstream.

If asm code specifies an UNWIND_HINT_EMPTY hint, don't warn if the
section ends unexpectedly.  This can happen with the xen-head.S code
because the hypercall_page is "text" but it's all zeros.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/ddafe199dd8797e40e3c2777373347eba1d65572.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index c0e26ad1fa7e..9b341584eb1b 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1757,11 +1757,14 @@ static int validate_branch(struct objtool_file *file, struct instruction *first,
 		if (insn->dead_end)
 			return 0;
 
-		insn = next_insn;
-		if (!insn) {
+		if (!next_insn) {
+			if (state.cfa.base == CFI_UNDEFINED)
+				return 0;
 			WARN("%s: unexpected end of section", sec->name);
 			return 1;
 		}
+
+		insn = next_insn;
 	}
 
 	return 0;