Move Double-Fault generation logic out of page fault exception generating function to cover more generic case. Signed-off-by: Eddie Dong <eddie.dong@xxxxxxxxx> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ab1fdac..51a8dad 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -162,12 +162,59 @@ void kvm_set_apic_base(struct kvm_vcpu *vcpu, u64 data) } EXPORT_SYMBOL_GPL(kvm_set_apic_base); +#define EXCPT_BENIGN 0 +#define EXCPT_CONTRIBUTORY 1 +#define EXCPT_PF 2 + +static int exception_class(int vector) +{ + if (vector == 14) + return EXCPT_PF; + else if (vector == 0 || (vector >= 10 && vector <= 13)) + return EXCPT_CONTRIBUTORY; + else + return EXCPT_BENIGN; +} + +static void kvm_multiple_exception(struct kvm_vcpu *vcpu, + unsigned nr, bool has_error, u32 error_code) +{ + u32 prev_nr; + int class1, class2; + + if (!vcpu->arch.exception.pending) { + 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; + return; + } + + /* to check exception */ + prev_nr = vcpu->arch.exception.nr; + class2 = exception_class(nr); + class1 = exception_class(prev_nr); + if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY) + || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) { + /* generate double fault per SDM Table 5-5 */ + printk(KERN_DEBUG "kvm: double fault 0x%x on 0x%x\n", + prev_nr, nr); + vcpu->arch.exception.pending = true; + vcpu->arch.exception.has_error_code = 1; + vcpu->arch.exception.nr = DF_VECTOR; + vcpu->arch.exception.error_code = 0; + if (prev_nr == DF_VECTOR) { + /* triple fault -> shutdown */ + set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests); + } + } else + printk(KERN_ERR "Exception 0x%x on 0x%x happens serially\n", + prev_nr, nr); +} + void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr) { - WARN_ON(vcpu->arch.exception.pending); - vcpu->arch.exception.pending = true; - vcpu->arch.exception.has_error_code = false; - vcpu->arch.exception.nr = nr; + kvm_multiple_exception(vcpu, nr, false, 0); } EXPORT_SYMBOL_GPL(kvm_queue_exception); @@ -176,18 +223,6 @@ void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long addr, { ++vcpu->stat.pf_guest; - if (vcpu->arch.exception.pending) { - if (vcpu->arch.exception.nr == PF_VECTOR) { - printk(KERN_DEBUG "kvm: inject_page_fault:" - " double fault 0x%lx\n", addr); - vcpu->arch.exception.nr = DF_VECTOR; - vcpu->arch.exception.error_code = 0; - } else if (vcpu->arch.exception.nr == DF_VECTOR) { - /* triple fault -> shutdown */ - set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests); - } - return; - } vcpu->arch.cr2 = addr; kvm_queue_exception_e(vcpu, PF_VECTOR, error_code); } @@ -200,11 +235,7 @@ EXPORT_SYMBOL_GPL(kvm_inject_nmi); void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code) { - WARN_ON(vcpu->arch.exception.pending); - vcpu->arch.exception.pending = true; - vcpu->arch.exception.has_error_code = true; - vcpu->arch.exception.nr = nr; - vcpu->arch.exception.error_code = error_code; + kvm_multiple_exception(vcpu, nr, true, error_code); } EXPORT_SYMBOL_GPL(kvm_queue_exception_e);
Attachment:
irq3.patch
Description: irq3.patch