[PATCH v4 30/39] arm64: kasan: Enable TBI EL1

[Andrey Konovalov]

From: Vincenzo Frascino <vincenzo.frascino at arm.com>

Hardware tag-based KASAN relies on Memory Tagging Extension (MTE) that is
built on top of the Top Byte Ignore (TBI) feature.

Enable in-kernel TBI when CONFIG_KASAN_HW_TAGS is turned on by enabling
the TCR_TBI1 bit in proc.S.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino at arm.com>
Co-developed-by: Andrey Konovalov <andreyknvl at google.com>
Signed-off-by: Andrey Konovalov <andreyknvl at google.com>
---
Change-Id: I91944903bc9c9c9044f0d50e74bcd6b9971d21ff
---
 arch/arm64/mm/proc.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 6c1a6621d769..7c3304fb15d9 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -46,7 +46,7 @@
 #endif
 
 #ifdef CONFIG_KASAN_HW_TAGS
-#define TCR_KASAN_HW_FLAGS SYS_TCR_EL1_TCMA1
+#define TCR_KASAN_HW_FLAGS SYS_TCR_EL1_TCMA1 | TCR_TBI1
 #else
 #define TCR_KASAN_HW_FLAGS 0
 #endif
-- 
2.28.0.709.gb0816b6eb0-goog