From 9b3b2f00291e1abd54bff345761a7fadd8df4daa Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 17 Dec 2024 14:23:14 +0000 Subject: [PATCH] KVM: arm64: nv: Accelerate EL0 counter accesses from hypervisor context Similarly to handling the physical timer accesses early when FEAT_ECV causes a trap, we try to handle the physical counter without returning to the general sysreg handling. More surprisingly, we introduce something similar for the virtual counter. Although this isn't necessary yet, it will prove useful on systems that have a broken CNTVOFF_EL2 implementation. Yes, they exist. Acked-by: Oliver Upton Link: https://lore.kernel.org/r/20241217142321.763801-7-maz@kernel.org Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/vhe/switch.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index 51119d58ecff..ef344bcff09a 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -324,6 +324,10 @@ static bool kvm_hyp_handle_timer(struct kvm_vcpu *vcpu, u64 *exit_code) val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0); } break; + case SYS_CNTPCT_EL0: + case SYS_CNTPCTSS_EL0: + val = compute_counter_value(vcpu_hptimer(vcpu)); + break; case SYS_CNTV_CTL_EL02: val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0); break; @@ -342,6 +346,10 @@ static bool kvm_hyp_handle_timer(struct kvm_vcpu *vcpu, u64 *exit_code) else val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0); break; + case SYS_CNTVCT_EL0: + case SYS_CNTVCTSS_EL0: + val = compute_counter_value(vcpu_hvtimer(vcpu)); + break; default: return false; }