[PATCH 09/10] KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct

Paolo Bonzini
2022-10-27T16:49:58Z

This allows making some fields optional, as will be the case soon
for SMM-related data.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/x86.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f6adb4145759..5959f74c5a0a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5056,16 +5056,15 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
ex->pending && ex->has_payload)
kvm_deliver_exception_payload(vcpu, ex);

+ memset(events, 0, sizeof(events));
+
/*
* The API doesn't provide the instruction length for software
* exceptions, so don't report them. As long as the guest RIP
* isn't advanced, we should expect to encounter the exception
* again.
*/
- if (kvm_exception_is_soft(ex->vector)) {
- events->exception.injected = 0;
- events->exception.pending = 0;
- } else {
+ if (!kvm_exception_is_soft(ex->vector)) {
events->exception.injected = ex->injected;
events->exception.pending = ex->pending;
/*
@@ -5085,15 +5084,13 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
events->interrupt.injected =
vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft;
events->interrupt.nr = vcpu->arch.interrupt.nr;
- events->interrupt.soft = 0;
events->interrupt.shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);

events->nmi.injected = vcpu->arch.nmi_injected;
events->nmi.pending = vcpu->arch.nmi_pending != 0;
events->nmi.masked = static_call(kvm_x86_get_nmi_mask)(vcpu);
- events->nmi.pad = 0;

- events->sipi_vector = 0; /* never valid when reporting to user space */
+ /* events->sipi_vector is never valid when reporting to user space */

events->smi.smm = is_smm(vcpu);
events->smi.pending = vcpu->arch.smi_pending;
@@ -5110,8 +5107,6 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
events->triple_fault.pending = kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu);
events->flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT;
}
-
- memset(&events->reserved, 0, sizeof(events->reserved));
}

static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
--
2.31.1