diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ed575c5655ddc0941bea300d75dbb8d585e9d258..c0706022d22f36525ead6d17c957e77cc262af57 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -52,6 +52,9 @@
#define KVM_DIRTY_LOG_MANUAL_CAPS (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | \
KVM_DIRTY_LOG_INITIALLY_SET)
+#define KVM_BUS_LOCK_DETECTION_VALID_MODE (KVM_BUS_LOCK_DETECTION_OFF | \
+ KVM_BUS_LOCK_DETECTION_EXIT)
+
/* x86-specific vcpu->requests bit members */
#define KVM_REQ_MIGRATE_TIMER KVM_ARCH_REQ(0)
#define KVM_REQ_REPORT_TPR_ACCESS KVM_ARCH_REQ(1)
@@ -996,6 +999,8 @@ struct kvm_arch {
struct msr_bitmap_range ranges[16];
} msr_filter;
+ bool bus_lock_detection_enabled;
+
struct kvm_pmu_event_filter *pmu_event_filter;
struct task_struct *nx_lpage_recovery_thread;
@@ -1418,6 +1423,8 @@ extern u8 kvm_tsc_scaling_ratio_frac_bits;
extern u64 kvm_max_tsc_scaling_ratio;
/* 1ull << kvm_tsc_scaling_ratio_frac_bits */
extern u64 kvm_default_tsc_scaling_ratio;
+/* bus lock detection supported? */
+extern bool kvm_has_bus_lock_exit;
extern u64 kvm_mce_cap_supported;
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 38ca445a84295f7e9e1fc73e390e07bda3299da6..358707f60d998181533c1c2d7976c16436f96d64 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -73,6 +73,7 @@
#define SECONDARY_EXEC_PT_USE_GPA VMCS_CONTROL_BIT(PT_USE_GPA)
#define SECONDARY_EXEC_TSC_SCALING VMCS_CONTROL_BIT(TSC_SCALING)
#define SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE VMCS_CONTROL_BIT(USR_WAIT_PAUSE)
+#define SECONDARY_EXEC_BUS_LOCK_DETECTION VMCS_CONTROL_BIT(BUS_LOCK_DETECTION)
#define PIN_BASED_EXT_INTR_MASK VMCS_CONTROL_BIT(INTR_EXITING)
#define PIN_BASED_NMI_EXITING VMCS_CONTROL_BIT(NMI_EXITING)
diff --git a/arch/x86/include/asm/vmxfeatures.h b/arch/x86/include/asm/vmxfeatures.h
index 9915990fd8cfab51a9cd287017e2d71d93f1f3f0..d9a74681a77d5851bc272cac79106c863b2e301f 100644
--- a/arch/x86/include/asm/vmxfeatures.h
+++ b/arch/x86/include/asm/vmxfeatures.h
@@ -83,5 +83,6 @@
#define VMX_FEATURE_TSC_SCALING ( 2*32+ 25) /* Scale hardware TSC when read in guest */
#define VMX_FEATURE_USR_WAIT_PAUSE ( 2*32+ 26) /* Enable TPAUSE, UMONITOR, UMWAIT in guest */
#define VMX_FEATURE_ENCLV_EXITING ( 2*32+ 28) /* "" VM-Exit on ENCLV (leaf dependent) */
+#define VMX_FEATURE_BUS_LOCK_DETECTION ( 2*32+ 30) /* "" VM-Exit when bus lock caused */
#endif /* _ASM_X86_VMXFEATURES_H */
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 8e76d3701db3f2432c91c9bd32623202547593b1..5a3022c8af82b8af1b88e5ed9d8b9af8afc5c9dd 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -112,6 +112,7 @@ struct kvm_ioapic_state {
#define KVM_NR_IRQCHIPS 3
#define KVM_RUN_X86_SMM (1 << 0)
+#define KVM_RUN_X86_BUS_LOCK (1 << 1)
/* for KVM_GET_REGS and KVM_SET_REGS */
struct kvm_regs {
diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h
index ada955c5ebb6055d7d71d12e20f578dfe6d1ab91..b8e650a985e358f9ef91c140d910a781f93edd7b 100644
--- a/arch/x86/include/uapi/asm/vmx.h
+++ b/arch/x86/include/uapi/asm/vmx.h
@@ -89,6 +89,7 @@
#define EXIT_REASON_XRSTORS 64
#define EXIT_REASON_UMWAIT 67
#define EXIT_REASON_TPAUSE 68
+#define EXIT_REASON_BUS_LOCK 74
#define VMX_EXIT_REASONS \
{ EXIT_REASON_EXCEPTION_NMI, "EXCEPTION_NMI" }, \
@@ -150,7 +151,8 @@
{ EXIT_REASON_XSAVES, "XSAVES" }, \
{ EXIT_REASON_XRSTORS, "XRSTORS" }, \
{ EXIT_REASON_UMWAIT, "UMWAIT" }, \
- { EXIT_REASON_TPAUSE, "TPAUSE" }
+ { EXIT_REASON_TPAUSE, "TPAUSE" }, \
+ { EXIT_REASON_BUS_LOCK, "BUS_LOCK" }
#define VMX_EXIT_REASON_FLAGS \
{ VMX_EXIT_REASONS_FAILED_VMENTRY, "FAILED_VMENTRY" }
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index 3a1861403d73ad7706f17092f783d1b327101809..5366ccdd134c9b8c555e93ab8f1af691e255e3b6 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -262,6 +262,12 @@ static inline bool cpu_has_vmx_tsc_scaling(void)
SECONDARY_EXEC_TSC_SCALING;
}
+static inline bool cpu_has_vmx_bus_lock_detection(void)
+{
+ return vmcs_config.cpu_based_2nd_exec_ctrl &
+ SECONDARY_EXEC_BUS_LOCK_DETECTION;
+}
+
static inline bool cpu_has_vmx_apicv(void)
{
return cpu_has_vmx_apic_register_virt() &&
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 880a2617820cbfb0fd11547b489c2ada7fc46ed7..af8d3a2db3d2165b53adeef68b8c61dcf44fb4b1 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2428,7 +2428,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE |
SECONDARY_EXEC_PT_USE_GPA |
SECONDARY_EXEC_PT_CONCEAL_VMX |
- SECONDARY_EXEC_ENABLE_VMFUNC;
+ SECONDARY_EXEC_ENABLE_VMFUNC |
+ SECONDARY_EXEC_BUS_LOCK_DETECTION;
if (cpu_has_sgx())
opt2 |= SECONDARY_EXEC_ENCLS_EXITING;
if (adjust_vmx_controls(min2, opt2,
@@ -4269,6 +4270,9 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx)
vmx_adjust_sec_exec_control(vmx, &exec_control, waitpkg, WAITPKG,
ENABLE_USR_WAIT_PAUSE, false);
+ if (!vcpu->kvm->arch.bus_lock_detection_enabled)
+ exec_control &= ~SECONDARY_EXEC_BUS_LOCK_DETECTION;
+
vmx->secondary_exec_control = exec_control;
}
@@ -5600,6 +5604,13 @@ static int handle_encls(struct kvm_vcpu *vcpu)
return 1;
}
+static int handle_bus_lock_vmexit(struct kvm_vcpu *vcpu)
+{
+ vcpu->run->exit_reason = KVM_EXIT_X86_BUS_LOCK;
+ vcpu->run->flags |= KVM_RUN_X86_BUS_LOCK;
+ return 0;
+}
+
/*
* The exit handlers return 1 if the exit was handled fully and guest execution
* may resume. Otherwise they set the kvm_run parameter to indicate what needs
@@ -5656,6 +5667,7 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
[EXIT_REASON_VMFUNC] = handle_vmx_instruction,
[EXIT_REASON_PREEMPTION_TIMER] = handle_preemption_timer,
[EXIT_REASON_ENCLS] = handle_encls,
+ [EXIT_REASON_BUS_LOCK] = handle_bus_lock_vmexit,
};
static const int kvm_vmx_max_exit_handlers =
@@ -5908,7 +5920,7 @@ void dump_vmcs(void)
* The guest has exited. See if we can fix it or if we need userspace
* assistance.
*/
-static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
+static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
union vmx_exit_reason exit_reason = vmx->exit_reason;
@@ -6061,6 +6073,25 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
return 0;
}
+static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
+{
+ int ret = __vmx_handle_exit(vcpu, exit_fastpath);
+
+ /*
+ * Even when current exit reason is handled by KVM internally, we
+ * still need to exit to user space when bus lock detected to inform
+ * that there is a bus lock in guest.
+ */
+ if (to_vmx(vcpu)->exit_reason.bus_lock_detected) {
+ if (ret > 0)
+ vcpu->run->exit_reason = KVM_EXIT_X86_BUS_LOCK;
+
+ vcpu->run->flags |= KVM_RUN_X86_BUS_LOCK;
+ return 0;
+ }
+ return ret;
+}
+
/*
* Software based L1D cache flush which is used when microcode providing
* the cache control MSR is not loaded.
@@ -7812,6 +7843,8 @@ static __init int hardware_setup(void)
kvm_tsc_scaling_ratio_frac_bits = 48;
}
+ kvm_has_bus_lock_exit = cpu_has_vmx_bus_lock_detection();
+
set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
if (enable_ept)
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 4dd71b7494eacfd0560cae93b22c0b704a83c5e5..cf335e94f198cd984a9bde4313dcb4bc8c8bd827 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -83,7 +83,7 @@ union vmx_exit_reason {
u32 reserved23 : 1;
u32 reserved24 : 1;
u32 reserved25 : 1;
- u32 reserved26 : 1;
+ u32 bus_lock_detected : 1;
u32 enclave_mode : 1;
u32 smi_pending_mtf : 1;
u32 smi_from_vmx_root : 1;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 90a2335498a285eb2242bc78268f201f69d6daa8..8719877fe7990176d2ec338cd46da664aa959683 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -136,6 +136,8 @@ u64 __read_mostly kvm_max_tsc_scaling_ratio;
EXPORT_SYMBOL_GPL(kvm_max_tsc_scaling_ratio);
u64 __read_mostly kvm_default_tsc_scaling_ratio;
EXPORT_SYMBOL_GPL(kvm_default_tsc_scaling_ratio);
+bool __read_mostly kvm_has_bus_lock_exit;
+EXPORT_SYMBOL_GPL(kvm_has_bus_lock_exit);
/* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */
static u32 __read_mostly tsc_tolerance_ppm = 250;
@@ -3843,6 +3845,13 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_STEAL_TIME:
r = sched_info_on();
break;
+ case KVM_CAP_X86_BUS_LOCK_EXIT:
+ if (kvm_has_bus_lock_exit)
+ r = KVM_BUS_LOCK_DETECTION_OFF |
+ KVM_BUS_LOCK_DETECTION_EXIT;
+ else
+ r = 0;
+ break;
default:
break;
}
@@ -5298,6 +5307,20 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
kvm->arch.user_space_msr_mask = cap->args[0];
r = 0;
break;
+ case KVM_CAP_X86_BUS_LOCK_EXIT:
+ r = -EINVAL;
+ if (cap->args[0] & ~KVM_BUS_LOCK_DETECTION_VALID_MODE)
+ break;
+
+ if ((cap->args[0] & KVM_BUS_LOCK_DETECTION_OFF) &&
+ (cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT))
+ break;
+
+ if (kvm_has_bus_lock_exit &&
+ cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT)
+ kvm->arch.bus_lock_detection_enabled = true;
+ r = 0;
+ break;
default:
r = -EINVAL;
break;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 07c194e2c302ca344ba7341f46c1c910f4b749f2..dfe3ba5cf262ab1bfb050ced8d4329f8e10889e9 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -252,6 +252,7 @@ struct kvm_hyperv_exit {
#define KVM_EXIT_X86_WRMSR 30
#define KVM_EXIT_DIRTY_RING_FULL 31
#define KVM_EXIT_AP_RESET_HOLD 32
+#define KVM_EXIT_X86_BUS_LOCK 33
/* For KVM_EXIT_INTERNAL_ERROR */
/* Emulate instruction failed. */
@@ -1058,6 +1059,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_ENFORCE_PV_FEATURE_CPUID 190
#define KVM_CAP_SYS_HYPERV_CPUID 191
#define KVM_CAP_DIRTY_LOG_RING 192
+#define KVM_CAP_X86_BUS_LOCK_EXIT 193
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1774,4 +1776,7 @@ struct kvm_dirty_gfn {
__u64 offset;
};
+#define KVM_BUS_LOCK_DETECTION_OFF (1 << 0)
+#define KVM_BUS_LOCK_DETECTION_EXIT (1 << 1)
+
#endif /* __LINUX_KVM_H */