[Qemu-devel] [PATCH 4/4] target/arm: Enable TBI for user-only

[Richard Henderson <richard.henderson@linaro.org>]

This has been enabled in the linux kernel since v3.11
(commit d50240a5f6cea, 2013-09-03,
"arm64: mm: permit use of tagged pointers at EL0").

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/cpu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 14bc24a35a..5eff6995ee 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -174,6 +174,12 @@ static void arm_cpu_reset(CPUState *s)
         env->vfp.zcr_el[1] = cpu->sve_max_vq - 1;
         env->vfp.zcr_el[2] = env->vfp.zcr_el[1];
         env->vfp.zcr_el[3] = env->vfp.zcr_el[1];
+        /*
+         * Enable TBI0 and TBI1.  While the real kernel only enables TBI0,
+         * turning on both here will produce smaller code and otherwise
+         * make no difference to the user-level emulation.
+         */
+        env->cp15.tcr_el[1].raw_tcr = (3ULL << 37);
 #else
         /* Reset into the highest available EL */
         if (arm_feature(env, ARM_FEATURE_EL3)) {
-- 
2.17.2