[PATCH v3 11/17] KVM: arm64: Disable TTBR1_EL2 when using ARM64_KVM_HVHE

Marc Zyngier
2023-06-09T16:47:29Z

When using hVHE, we end-up with two TTBRs at EL2. That's great,
but we're not quite ready for this just yet.

Disable TTBR1_EL2 by setting TCR_EL2.EPD1 so that we only
translate via TTBR0_EL2.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/arm.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index c12276dd2cf4..35b32cb6faa5 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1666,7 +1666,13 @@ static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)

params->mair_el2 = read_sysreg(mair_el1);

- tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1;
+ tcr = read_sysreg(tcr_el1);
+ if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
+ tcr |= TCR_EPD1_MASK;
+ } else {
+ tcr &= TCR_EL2_MASK;
+ tcr |= TCR_EL2_RES1;
+ }
tcr &= ~TCR_T0SZ_MASK;
tcr |= TCR_T0SZ(hyp_va_bits);
params->tcr_el2 = tcr;
--
2.34.1