From 9b0e04f3abc04f00569622f8ad738dce626e9d1b Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 5 Feb 2019 17:44:12 -0500 Subject: [PATCH] target/arm: Enable TBI for user-only 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"). Backports commit f6a148fef63698826e69ca91cc11877ab1ed786f from qemu --- qemu/target/arm/cpu.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/qemu/target/arm/cpu.c b/qemu/target/arm/cpu.c index be9f3192..a667572e 100644 --- a/qemu/target/arm/cpu.c +++ b/qemu/target/arm/cpu.c @@ -192,6 +192,12 @@ 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)) {