android-5.4/ANDROID-arm64-add-__nocfi-to-__apply_alternatives.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Sami Tolvanen <samitolvanen@google.com>
Date: Fri, 16 Aug 2019 11:32:43 -0700
Subject: ANDROID: arm64: add __nocfi to __apply_alternatives

__apply_alternatives makes indirect calls to functions whose address is
taken in assembly code using the alternative_cb macro. With CFI enabled
using non-canonical jump tables, the compiler isn't able to replace the
function reference with the jump table reference, which trips CFI.

Bug: 145210207
Change-Id: I6cdd164f9315c0aa16a1427ab1a67cfa8aad3ffd
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
 arch/arm64/kernel/alternative.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c
index d1757ef1b1e7..f1e598d6bc31 100644
--- a/arch/arm64/kernel/alternative.c
+++ b/arch/arm64/kernel/alternative.c
@@ -144,8 +144,8 @@ static void clean_dcache_range_nopatch(u64 start, u64 end)
 	} while (cur += d_size, cur < end);
 }
 
-static void __apply_alternatives(void *alt_region,  bool is_module,
-				 unsigned long *feature_mask)
+static void __nocfi __apply_alternatives(void *alt_region,  bool is_module,
+					 unsigned long *feature_mask)
 {
 	struct alt_instr *alt;
 	struct alt_region *region = alt_region;