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Subject[PATCH 3/4] KVM: x86: pass struct kvm_queued_exception to kvm_multiple_exception
Date
Avoid early overwriting of vcpu->arch.exception.nested_apf, and
make it easier to add CR2 or DR6 in the future.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/x86.c | 79 ++++++++++++++++++++++++++++++++----------------------
1 file changed, 47 insertions(+), 32 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4e699238a113..88b91114c5a8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -381,25 +381,14 @@ static int exception_type(int vector)
}

static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
- unsigned nr, bool has_error, u32 error_code,
- bool reinject)
+ struct kvm_queued_exception ex)
{
u32 prev_nr;
int class1, class2;

kvm_make_request(KVM_REQ_EVENT, vcpu);
-
- if (!vcpu->arch.exception.pending) {
- queue:
- if (has_error && !is_protmode(vcpu))
- has_error = false;
- vcpu->arch.exception.pending = true;
- vcpu->arch.exception.has_error_code = has_error;
- vcpu->arch.exception.nr = nr;
- vcpu->arch.exception.error_code = error_code;
- vcpu->arch.exception.reinject = reinject;
- return;
- }
+ if (!vcpu->arch.exception.pending)
+ goto queue;

/* to check exception */
prev_nr = vcpu->arch.exception.nr;
@@ -409,30 +398,43 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
return;
}
class1 = exception_class(prev_nr);
- class2 = exception_class(nr);
+ class2 = exception_class(ex.nr);
if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)
|| (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
/* generate double fault per SDM Table 5-5 */
- vcpu->arch.exception.pending = true;
- vcpu->arch.exception.has_error_code = true;
- vcpu->arch.exception.nr = DF_VECTOR;
- vcpu->arch.exception.error_code = 0;
- } else
- /* replace previous exception with a new one in a hope
- that instruction re-execution will regenerate lost
- exception */
- goto queue;
+ ex.pending = true;
+ ex.has_error_code = true;
+ ex.nr = DF_VECTOR;
+ ex.error_code = 0;
+ }
+
+ /*
+ * Else replace previous exception with a new one in a hope
+ * that instruction re-execution will regenerate lost
+ * exception.
+ */
+
+queue:
+ ex.pending = true;
+ ex.has_error_code = ex.has_error_code && is_protmode(vcpu);
+ vcpu->arch.exception = ex;
+ return;
}

void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr)
{
- kvm_multiple_exception(vcpu, nr, false, 0, false);
+ kvm_multiple_exception(vcpu, ((struct kvm_queued_exception) {
+ .nr = nr
+ }));
}
EXPORT_SYMBOL_GPL(kvm_queue_exception);

void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr)
{
- kvm_multiple_exception(vcpu, nr, false, 0, true);
+ kvm_multiple_exception(vcpu, ((struct kvm_queued_exception) {
+ .nr = nr,
+ .reinject = true
+ }));
}
EXPORT_SYMBOL_GPL(kvm_requeue_exception);

@@ -449,14 +451,18 @@ int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err)

void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault)
{
+ bool nested_apf = is_guest_mode(vcpu) && fault->async_page_fault;
++vcpu->stat.pf_guest;
- vcpu->arch.exception.nested_apf =
- is_guest_mode(vcpu) && fault->async_page_fault;
- if (vcpu->arch.exception.nested_apf)
+ if (nested_apf)
vcpu->arch.apf.nested_apf_token = fault->address;
else
vcpu->arch.cr2 = fault->address;
- kvm_queue_exception_e(vcpu, PF_VECTOR, fault->error_code);
+ kvm_multiple_exception(vcpu, ((struct kvm_queued_exception) {
+ .nr = PF_VECTOR,
+ .nested_apf = nested_apf,
+ .has_error_code = true,
+ .error_code = fault->error_code
+ }));
}
EXPORT_SYMBOL_GPL(kvm_inject_page_fault);

@@ -479,13 +485,22 @@ void kvm_inject_nmi(struct kvm_vcpu *vcpu)

void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code)
{
- kvm_multiple_exception(vcpu, nr, true, error_code, false);
+ kvm_multiple_exception(vcpu, ((struct kvm_queued_exception) {
+ .nr = nr,
+ .has_error_code = true,
+ .error_code = error_code
+ }));
}
EXPORT_SYMBOL_GPL(kvm_queue_exception_e);

void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code)
{
- kvm_multiple_exception(vcpu, nr, true, error_code, true);
+ kvm_multiple_exception(vcpu, ((struct kvm_queued_exception) {
+ .nr = nr,
+ .has_error_code = true,
+ .error_code = error_code,
+ .reinject = true
+ }));
}
EXPORT_SYMBOL_GPL(kvm_requeue_exception_e);

--
1.8.3.1

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