- move req_immediate_exit variable from arch specific to common code.
- remove arch specific callback .request_immediate_exit and move the code
down to the arch's vcpu_run's code.
No functional change is intended.
Signed-off-by: Maxim Levitsky <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 -
arch/x86/include/asm/kvm_host.h | 5 ++---
arch/x86/kvm/svm/svm.c | 5 +++--
arch/x86/kvm/vmx/vmx.c | 18 ++++++-----------
arch/x86/kvm/vmx/vmx.h | 2 --
arch/x86/kvm/x86.c | 31 +++++++++++++-----------------
6 files changed, 24 insertions(+), 38 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e3054e3e46d52d..f654a7f4cc8c0c 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -101,7 +101,6 @@ KVM_X86_OP(write_tsc_multiplier)
KVM_X86_OP(get_exit_info)
KVM_X86_OP(check_intercept)
KVM_X86_OP(handle_exit_irqoff)
-KVM_X86_OP(request_immediate_exit)
KVM_X86_OP(sched_in)
KVM_X86_OP_OPTIONAL(update_cpu_dirty_logging)
KVM_X86_OP_OPTIONAL(vcpu_blocking)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 17715cb8731d5d..383a1d0cc0743b 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1011,6 +1011,8 @@ struct kvm_vcpu_arch {
*/
bool pdptrs_from_userspace;
+ bool req_immediate_exit;
+
#if IS_ENABLED(CONFIG_HYPERV)
hpa_t hv_root_tdp;
#endif
@@ -1690,8 +1692,6 @@ struct kvm_x86_ops {
struct x86_exception *exception);
void (*handle_exit_irqoff)(struct kvm_vcpu *vcpu);
- void (*request_immediate_exit)(struct kvm_vcpu *vcpu);
-
void (*sched_in)(struct kvm_vcpu *kvm, int cpu);
/*
@@ -2176,7 +2176,6 @@ extern bool kvm_find_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn);
int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu);
int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err);
-void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu);
void __user *__x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
u32 size);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 9507df93f410a6..60b130b7f9d510 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4176,6 +4176,9 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
clgi();
kvm_load_guest_xsave_state(vcpu);
+ if (vcpu->arch.req_immediate_exit)
+ smp_send_reschedule(vcpu->cpu);
+
kvm_wait_lapic_expire(vcpu);
/*
@@ -5004,8 +5007,6 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
.check_intercept = svm_check_intercept,
.handle_exit_irqoff = svm_handle_exit_irqoff,
- .request_immediate_exit = __kvm_request_immediate_exit,
-
.sched_in = svm_sched_in,
.nested_ops = &svm_nested_ops,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 72e3943f36935c..eb7e42235e8811 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -67,6 +67,8 @@
#include "x86.h"
#include "smm.h"
+#include <trace/events/ipi.h>
+
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
@@ -1288,8 +1290,6 @@ 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
@@ -5996,7 +5996,7 @@ static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- if (!vmx->req_immediate_exit &&
+ if (!vcpu->arch.req_immediate_exit &&
!unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) {
kvm_lapic_expired_hv_timer(vcpu);
return EXIT_FASTPATH_REENTER_GUEST;
@@ -7154,7 +7154,7 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu)
u64 tscl;
u32 delta_tsc;
- if (vmx->req_immediate_exit) {
+ if (vcpu->arch.req_immediate_exit) {
vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, 0);
vmx->loaded_vmcs->hv_timer_soft_disabled = false;
} else if (vmx->hv_deadline_tsc != -1) {
@@ -7357,6 +7357,8 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
if (enable_preemption_timer)
vmx_update_hv_timer(vcpu);
+ else if (vcpu->arch.req_immediate_exit)
+ smp_send_reschedule(vcpu->cpu);
kvm_wait_lapic_expire(vcpu);
@@ -7902,11 +7904,6 @@ 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)
{
@@ -8315,8 +8312,6 @@ 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,
@@ -8574,7 +8569,6 @@ 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 c2130d2c8e24bb..4dabd16a3d7180 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -330,8 +330,6 @@ 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;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9f18b06bbda66b..dfb7d25ed94f26 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10049,8 +10049,7 @@ static void kvm_inject_exception(struct kvm_vcpu *vcpu)
* ordering between that side effect, the instruction completing, _and_ the
* delivery of the asynchronous event.
*/
-static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
- bool *req_immediate_exit)
+static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu)
{
bool can_inject;
int r;
@@ -10227,8 +10226,9 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
if (is_guest_mode(vcpu) &&
kvm_x86_ops.nested_ops->has_events &&
- kvm_x86_ops.nested_ops->has_events(vcpu))
- *req_immediate_exit = true;
+ kvm_x86_ops.nested_ops->has_events(vcpu)) {
+ vcpu->arch.req_immediate_exit = true;
+ }
/*
* KVM must never queue a new exception while injecting an event; KVM
@@ -10245,10 +10245,9 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
WARN_ON_ONCE(vcpu->arch.exception.pending ||
vcpu->arch.exception_vmexit.pending);
return 0;
-
out:
if (r == -EBUSY) {
- *req_immediate_exit = true;
+ vcpu->arch.req_immediate_exit = true;
r = 0;
}
return r;
@@ -10475,12 +10474,6 @@ static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
static_call_cond(kvm_x86_set_apic_access_page_addr)(vcpu);
}
-void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu)
-{
- smp_send_reschedule(vcpu->cpu);
-}
-EXPORT_SYMBOL_GPL(__kvm_request_immediate_exit);
-
/*
* Called within kvm->srcu read side.
* Returns 1 to let vcpu_run() continue the guest execution loop without
@@ -10495,7 +10488,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_cpu_accept_dm_intr(vcpu);
fastpath_t exit_fastpath;
- bool req_immediate_exit = false;
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu)) {
@@ -10657,7 +10649,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
goto out;
}
- r = kvm_check_and_inject_events(vcpu, &req_immediate_exit);
+ r = kvm_check_and_inject_events(vcpu);
if (r < 0) {
r = 0;
goto out;
@@ -10726,10 +10718,9 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
goto cancel_injection;
}
- if (req_immediate_exit) {
+
+ if (vcpu->arch.req_immediate_exit)
kvm_make_request(KVM_REQ_EVENT, vcpu);
- static_call(kvm_x86_request_immediate_exit)(vcpu);
- }
fpregs_assert_state_consistent();
if (test_thread_flag(TIF_NEED_FPU_LOAD))
@@ -10761,6 +10752,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
(kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED));
exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu);
+
if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
break;
@@ -10776,6 +10768,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
++vcpu->stat.exits;
}
+ vcpu->arch.req_immediate_exit = false;
/*
* Do this here before restoring debug registers on the host. And
* since we do this before handling the vmexit, a DR access vmexit
@@ -10863,8 +10856,10 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
return r;
cancel_injection:
- if (req_immediate_exit)
+ if (vcpu->arch.req_immediate_exit) {
+ vcpu->arch.req_immediate_exit = false;
kvm_make_request(KVM_REQ_EVENT, vcpu);
+ }
static_call(kvm_x86_cancel_injection)(vcpu);
if (unlikely(vcpu->arch.apic_attention))
kvm_lapic_sync_from_vapic(vcpu);
--
2.26.3
On 9/28/23 12:36, Maxim Levitsky wrote:
> @@ -4176,6 +4176,9 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
> clgi();
> kvm_load_guest_xsave_state(vcpu);
>
> + if (vcpu->arch.req_immediate_exit)
> + smp_send_reschedule(vcpu->cpu);
> +
This code is in a non-standard situation where IF=1 but interrupts are
effectively disabled. Better something like:
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index beea99c8e8e0..3b945de2d880 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4148,8 +4148,11 @@ static __no_kcsan fastpath_t svm_vcpu_run(
* is enough to force an immediate vmexit.
*/
disable_nmi_singlestep(svm);
+ vcpu->arch.req_immediate_exit = true;
+ }
+
+ if (vcpu->arch.req_immediate_exit)
smp_send_reschedule(vcpu->cpu);
- }
pre_svm_run(vcpu);
Paolo
On Fri, 2023-11-24 at 17:07 +0100, Paolo Bonzini wrote:
> On 9/28/23 12:36, Maxim Levitsky wrote:
> > @@ -4176,6 +4176,9 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
> > clgi();
> > kvm_load_guest_xsave_state(vcpu);
> >
> > + if (vcpu->arch.req_immediate_exit)
> > + smp_send_reschedule(vcpu->cpu);
> > +
>
> This code is in a non-standard situation where IF=1 but interrupts are
> effectively disabled. Better something like:
>
> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> index beea99c8e8e0..3b945de2d880 100644
> --- a/arch/x86/kvm/svm/svm.c
> +++ b/arch/x86/kvm/svm/svm.c
> @@ -4148,8 +4148,11 @@ static __no_kcsan fastpath_t svm_vcpu_run(
> * is enough to force an immediate vmexit.
> */
> disable_nmi_singlestep(svm);
> + vcpu->arch.req_immediate_exit = true;
> + }
> +
> + if (vcpu->arch.req_immediate_exit)
> smp_send_reschedule(vcpu->cpu);
> - }
>
> pre_svm_run(vcpu);
>
>
> Paolo
>
Actually IF=0 at that point. We disable IF before we call svm_vcpu_run, at
vcpu_enter_guest().
Then we disable GIF, and we re-enable IF only right before VMRUN, in fact vmrun is
in the interrupt shadow although that doesn't really matter since GIF=0.
However I don't mind implementing the change you suggested, I don't think it will
affect anything.
Best regards,
Maxim Levitsky