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authorSuzuki K Poulose <suzuki.poulose@arm.com>2021-04-05 17:42:54 +0100
committerMathieu Poirier <mathieu.poirier@linaro.org>2021-04-06 16:05:28 -0600
commita1319260bf62951e279ea228f682bf4b8834a3c2 (patch)
tree856ce34e19e6189e4e931e6f58ec2df84dec1f13 /arch/arm64/kvm/hyp/nvhe/switch.c
parentd2602bb4f5a450642b96d467e27e6d5d3ef7fa54 (diff)
arm64: KVM: Enable access to TRBE support for host
For a nvhe host, the EL2 must allow the EL1&0 translation regime for TraceBuffer (MDCR_EL2.E2TB == 0b11). This must be saved/restored over a trip to the guest. Also, before entering the guest, we must flush any trace data if the TRBE was enabled. And we must prohibit the generation of trace while we are in EL1 by clearing the TRFCR_EL1. For vhe, the EL2 must prevent the EL1 access to the Trace Buffer. The MDCR_EL2 bit definitions for TRBE are available here : https://developer.arm.com/documentation/ddi0601/2020-12/AArch64-Registers/ Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210405164307.1720226-8-suzuki.poulose@arm.com Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Diffstat (limited to 'arch/arm64/kvm/hyp/nvhe/switch.c')
-rw-r--r--arch/arm64/kvm/hyp/nvhe/switch.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 68ab6b4d5141..736805232521 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -95,6 +95,7 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu)
mdcr_el2 &= MDCR_EL2_HPMN_MASK;
mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
+ mdcr_el2 |= MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT;
write_sysreg(mdcr_el2, mdcr_el2);
if (is_protected_kvm_enabled())