From fc17de99019a479e9df27cb532624d1f14cb13f1 Mon Sep 17 00:00:00 2001 From: Isaku Yamahata Date: Sat, 22 Feb 2025 09:47:47 +0800 Subject: [PATCH] KVM: TDX: Wait lapic expire when timer IRQ was injected Call kvm_wait_lapic_expire() when POSTED_INTR_ON is set and the vector for LVTT is set in PIR before TD entry. KVM always assumes a timer IRQ was injected if APIC state is protected. For TDX guest, APIC state is protected and KVM injects timer IRQ via posted interrupt. To avoid unnecessary wait calls, only call kvm_wait_lapic_expire() when a timer IRQ was injected, i.e., POSTED_INTR_ON is set and the vector for LVTT is set in PIR. Add a helper to test PIR. Signed-off-by: Isaku Yamahata Co-developed-by: Binbin Wu Signed-off-by: Binbin Wu Message-ID: <20250222014757.897978-7-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/posted_intr.h | 5 +++++ arch/x86/kvm/vmx/tdx.c | 7 ++++++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/posted_intr.h b/arch/x86/include/asm/posted_intr.h index de788b400fba..bb107ebbe713 100644 --- a/arch/x86/include/asm/posted_intr.h +++ b/arch/x86/include/asm/posted_intr.h @@ -81,6 +81,11 @@ static inline bool pi_test_sn(struct pi_desc *pi_desc) return test_bit(POSTED_INTR_SN, (unsigned long *)&pi_desc->control); } +static inline bool pi_test_pir(int vector, struct pi_desc *pi_desc) +{ + return test_bit(vector, (unsigned long *)pi_desc->pir); +} + /* Non-atomic helpers */ static inline void __pi_set_sn(struct pi_desc *pi_desc) { diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 798ea5a5232e..b98eab24114c 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -969,9 +969,14 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit) trace_kvm_entry(vcpu, force_immediate_exit); - if (pi_test_on(&vt->pi_desc)) + if (pi_test_on(&vt->pi_desc)) { apic->send_IPI_self(POSTED_INTR_VECTOR); + if (pi_test_pir(kvm_lapic_get_reg(vcpu->arch.apic, APIC_LVTT) & + APIC_VECTOR_MASK, &vt->pi_desc)) + kvm_wait_lapic_expire(vcpu); + } + tdx_vcpu_enter_exit(vcpu); if (vt->host_debugctlmsr & ~TDX_DEBUGCTL_PRESERVED) -- 2.50.1