[PATCH] debug

[Sean Christopherson]

---
 arch/x86/kvm/vmx/vmx.c | 33 +++++++++++++++++++++++++++++----
 arch/x86/kvm/vmx/vmx.h |  1 +
 arch/x86/kvm/x86.c     |  1 +
 3 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index f18c2d8c7476..e83351c690d9 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4431,8 +4431,7 @@ static u32 vmx_vmexit_ctrl(void)
 	 * Not used by KVM and never set in vmcs01 or vmcs02, but emulated for
 	 * nested virtualization and thus allowed to be set in vmcs12.
 	 */
-	vmexit_ctrl &= ~(VM_EXIT_SAVE_IA32_PAT | VM_EXIT_SAVE_IA32_EFER |
-			 VM_EXIT_SAVE_VMX_PREEMPTION_TIMER);
+	vmexit_ctrl &= ~(VM_EXIT_SAVE_IA32_PAT | VM_EXIT_SAVE_IA32_EFER);
 
 	if (vmx_pt_mode_is_system())
 		vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP |
@@ -5997,6 +5996,8 @@ static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu,
 						   bool force_immediate_exit)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	u32 delta_tsc;
+	u64 tscl;
 
 	/*
 	 * In the *extremely* unlikely scenario that this is a spurious VM-Exit
@@ -6020,6 +6021,16 @@ static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu,
 	if (is_guest_mode(vcpu))
 		return EXIT_FASTPATH_NONE;
 
+	tscl = rdtsc();
+	if (vmx->hv_deadline_tsc > tscl)
+		delta_tsc = (u32)((vmx->hv_deadline_tsc - tscl) >> cpu_preemption_timer_multi);
+	else
+		delta_tsc = 0;
+
+	pr_warn("VMX timer exit, EXIT_REASON = %x, VMCS = %x, delta = %x\n",
+		vmcs_read32(VM_EXIT_REASON),
+		vmcs_read32(VMX_PREEMPTION_TIMER_VALUE), delta_tsc);
+
 	kvm_lapic_expired_hv_timer(vcpu);
 	return EXIT_FASTPATH_REENTER_GUEST;
 }
@@ -7197,6 +7208,8 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu, bool force_immediate_exit
 	u32 delta_tsc;
 
 	if (force_immediate_exit) {
+		trace_kvm_hypercall(0, 0, 0, 0, 0);
+		vmx->preemption_timer = 0;
 		vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, 0);
 		vmx->loaded_vmcs->hv_timer_soft_disabled = false;
 	} else if (vmx->hv_deadline_tsc != -1) {
@@ -7208,9 +7221,14 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu, bool force_immediate_exit
 		else
 			delta_tsc = 0;
 
+		trace_kvm_hypercall(tscl, vmx->hv_deadline_tsc, delta_tsc,
+				    ((vmx->hv_deadline_tsc - tscl) >> cpu_preemption_timer_multi),
+				    cpu_preemption_timer_multi);
+		vmx->preemption_timer = delta_tsc;
 		vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, delta_tsc);
 		vmx->loaded_vmcs->hv_timer_soft_disabled = false;
 	} else if (!vmx->loaded_vmcs->hv_timer_soft_disabled) {
+		trace_kvm_hypercall(-1, -1, -1, -1, -1);
 		vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, -1);
 		vmx->loaded_vmcs->hv_timer_soft_disabled = true;
 	}
@@ -7218,6 +7236,8 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu, bool force_immediate_exit
 
 void noinstr vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp)
 {
+	WARN_ON(!vmx->loaded_vmcs->hv_timer_soft_disabled &&
+		vmcs_read32(VMX_PREEMPTION_TIMER_VALUE) != vmx->preemption_timer);
 	if (unlikely(host_rsp != vmx->loaded_vmcs->host_state.rsp)) {
 		vmx->loaded_vmcs->host_state.rsp = host_rsp;
 		vmcs_writel(HOST_RSP, host_rsp);
@@ -8128,7 +8148,7 @@ int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
 	    delta_tsc && u64_shl_div_u64(delta_tsc,
 				kvm_caps.tsc_scaling_ratio_frac_bits,
 				vcpu->arch.l1_tsc_scaling_ratio, &delta_tsc))
-		return -ERANGE;
+		goto out_of_range;
 
 	/*
 	 * If the delta tsc can't fit in the 32 bit after the multi shift,
@@ -8137,11 +8157,16 @@ int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
 	 * on every vmentry is costly so we just use an hrtimer.
 	 */
 	if (delta_tsc >> (cpu_preemption_timer_multi + 32))
-		return -ERANGE;
+		goto out_of_range;
 
+	trace_kvm_hypercall(tscl, vmx->hv_deadline_tsc, delta_tsc, -1, -1);
 	vmx->hv_deadline_tsc = tscl + delta_tsc;
 	*expired = !delta_tsc;
 	return 0;
+
+out_of_range:
+	vmx->hv_deadline_tsc = -1;
+	return -ERANGE;
 }
 
 void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 42498fa63abb..ecafbb11519d 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -341,6 +341,7 @@ struct vcpu_vmx {
 
 	/* apic deadline value in host tsc */
 	u64 hv_deadline_tsc;
+	u32 preemption_timer;
 
 	unsigned long host_debugctlmsr;
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 994743266480..00847259bcc4 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -14024,6 +14024,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_write_tsc_offset);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_ple_window_update);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pml_full);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_hypercall);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pi_irte_update);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_unaccelerated_access);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_incomplete_ipi);

base-commit: 128c71b7f489d8115d29a487367c648f8acc8374
-- 
2.45.2.803.g4e1b14247a-goog


--FoqhM4pZbXonoqbf--