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-rw-r--r--arch/x86/kvm/vmx/nested.c2
-rw-r--r--arch/x86/kvm/vmx/vmx.c85
-rw-r--r--arch/x86/kvm/vmx/vmx.h2
3 files changed, 54 insertions, 35 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 6329a306856b..0cd977f22c4b 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4433,7 +4433,7 @@ static void sync_vmcs02_to_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
(vm_entry_controls_get(to_vmx(vcpu)) & VM_ENTRY_IA32E_MODE);
if (vmcs12->vm_exit_controls & VM_EXIT_SAVE_DEBUG_CONTROLS)
- kvm_get_dr(vcpu, 7, (unsigned long *)&vmcs12->guest_dr7);
+ vmcs12->guest_dr7 = vcpu->arch.dr7;
if (vmcs12->vm_exit_controls & VM_EXIT_SAVE_IA32_EFER)
vmcs12->guest_ia32_efer = vcpu->arch.efer;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 88a4ff200d04..fa3c3abb50e4 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -49,6 +49,8 @@
#include <asm/spec-ctrl.h>
#include <asm/vmx.h>
+#include <trace/events/ipi.h>
+
#include "capabilities.h"
#include "cpuid.h"
#include "hyperv.h"
@@ -1290,8 +1292,6 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
u16 fs_sel, gs_sel;
int i;
- vmx->req_immediate_exit = false;
-
/*
* Note that guest MSRs to be saved/restored can also be changed
* when guest state is loaded. This happens when guest transitions
@@ -5575,10 +5575,7 @@ static int handle_dr(struct kvm_vcpu *vcpu)
reg = DEBUG_REG_ACCESS_REG(exit_qualification);
if (exit_qualification & TYPE_MOV_FROM_DR) {
- unsigned long val;
-
- kvm_get_dr(vcpu, dr, &val);
- kvm_register_write(vcpu, reg, val);
+ kvm_register_write(vcpu, reg, kvm_get_dr(vcpu, dr));
err = 0;
} else {
err = kvm_set_dr(vcpu, dr, kvm_register_read(vcpu, reg));
@@ -6000,22 +5997,46 @@ static int handle_pml_full(struct kvm_vcpu *vcpu)
return 1;
}
-static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu)
+static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu,
+ bool force_immediate_exit)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- if (!vmx->req_immediate_exit &&
- !unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) {
- kvm_lapic_expired_hv_timer(vcpu);
+ /*
+ * In the *extremely* unlikely scenario that this is a spurious VM-Exit
+ * due to the timer expiring while it was "soft" disabled, just eat the
+ * exit and re-enter the guest.
+ */
+ if (unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled))
return EXIT_FASTPATH_REENTER_GUEST;
- }
- return EXIT_FASTPATH_NONE;
+ /*
+ * If the timer expired because KVM used it to force an immediate exit,
+ * then mission accomplished.
+ */
+ if (force_immediate_exit)
+ return EXIT_FASTPATH_EXIT_HANDLED;
+
+ /*
+ * If L2 is active, go down the slow path as emulating the guest timer
+ * expiration likely requires synthesizing a nested VM-Exit.
+ */
+ if (is_guest_mode(vcpu))
+ return EXIT_FASTPATH_NONE;
+
+ kvm_lapic_expired_hv_timer(vcpu);
+ return EXIT_FASTPATH_REENTER_GUEST;
}
static int handle_preemption_timer(struct kvm_vcpu *vcpu)
{
- handle_fastpath_preemption_timer(vcpu);
+ /*
+ * This non-fastpath handler is reached if and only if the preemption
+ * timer was being used to emulate a guest timer while L2 is active.
+ * All other scenarios are supposed to be handled in the fastpath.
+ */
+ WARN_ON_ONCE(!is_guest_mode(vcpu));
+ kvm_lapic_expired_hv_timer(vcpu);
return 1;
}
@@ -7155,13 +7176,13 @@ static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx)
msrs[i].host, false);
}
-static void vmx_update_hv_timer(struct kvm_vcpu *vcpu)
+static void vmx_update_hv_timer(struct kvm_vcpu *vcpu, bool force_immediate_exit)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
u64 tscl;
u32 delta_tsc;
- if (vmx->req_immediate_exit) {
+ if (force_immediate_exit) {
vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, 0);
vmx->loaded_vmcs->hv_timer_soft_disabled = false;
} else if (vmx->hv_deadline_tsc != -1) {
@@ -7214,13 +7235,22 @@ void noinstr vmx_spec_ctrl_restore_host(struct vcpu_vmx *vmx,
barrier_nospec();
}
-static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
+static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu,
+ bool force_immediate_exit)
{
+ /*
+ * If L2 is active, some VMX preemption timer exits can be handled in
+ * the fastpath even, all other exits must use the slow path.
+ */
+ if (is_guest_mode(vcpu) &&
+ to_vmx(vcpu)->exit_reason.basic != EXIT_REASON_PREEMPTION_TIMER)
+ return EXIT_FASTPATH_NONE;
+
switch (to_vmx(vcpu)->exit_reason.basic) {
case EXIT_REASON_MSR_WRITE:
return handle_fastpath_set_msr_irqoff(vcpu);
case EXIT_REASON_PREEMPTION_TIMER:
- return handle_fastpath_preemption_timer(vcpu);
+ return handle_fastpath_preemption_timer(vcpu, force_immediate_exit);
default:
return EXIT_FASTPATH_NONE;
}
@@ -7280,7 +7310,7 @@ out:
guest_state_exit_irqoff();
}
-static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
+static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
unsigned long cr3, cr4;
@@ -7307,7 +7337,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
return EXIT_FASTPATH_NONE;
}
- trace_kvm_entry(vcpu);
+ trace_kvm_entry(vcpu, force_immediate_exit);
if (vmx->ple_window_dirty) {
vmx->ple_window_dirty = false;
@@ -7366,7 +7396,9 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
vmx_passthrough_lbr_msrs(vcpu);
if (enable_preemption_timer)
- vmx_update_hv_timer(vcpu);
+ vmx_update_hv_timer(vcpu, force_immediate_exit);
+ else if (force_immediate_exit)
+ smp_send_reschedule(vcpu->cpu);
kvm_wait_lapic_expire(vcpu);
@@ -7430,10 +7462,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
vmx_recover_nmi_blocking(vmx);
vmx_complete_interrupts(vmx);
- if (is_guest_mode(vcpu))
- return EXIT_FASTPATH_NONE;
-
- return vmx_exit_handlers_fastpath(vcpu);
+ return vmx_exit_handlers_fastpath(vcpu, force_immediate_exit);
}
static void vmx_vcpu_free(struct kvm_vcpu *vcpu)
@@ -7913,11 +7942,6 @@ static __init void vmx_set_cpu_caps(void)
kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG);
}
-static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
-{
- to_vmx(vcpu)->req_immediate_exit = true;
-}
-
static int vmx_check_intercept_io(struct kvm_vcpu *vcpu,
struct x86_instruction_info *info)
{
@@ -8370,8 +8394,6 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
.check_intercept = vmx_check_intercept,
.handle_exit_irqoff = vmx_handle_exit_irqoff,
- .request_immediate_exit = vmx_request_immediate_exit,
-
.sched_in = vmx_sched_in,
.cpu_dirty_log_size = PML_ENTITY_NUM,
@@ -8631,7 +8653,6 @@ static __init int hardware_setup(void)
if (!enable_preemption_timer) {
vmx_x86_ops.set_hv_timer = NULL;
vmx_x86_ops.cancel_hv_timer = NULL;
- vmx_x86_ops.request_immediate_exit = __kvm_request_immediate_exit;
}
kvm_caps.supported_mce_cap |= MCG_LMCE_P;
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index e3b0985bb74a..65786dbe7d60 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -332,8 +332,6 @@ struct vcpu_vmx {
unsigned int ple_window;
bool ple_window_dirty;
- bool req_immediate_exit;
-
/* Support for PML */
#define PML_ENTITY_NUM 512
struct page *pml_pg;
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