diff options
| author | Avi Kivity <avi@redhat.com> | 2012-03-05 14:23:29 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2012-03-08 14:10:30 +0200 |
| commit | 3e515705a1f46beb1c942bb8043c16f8ac7b1e9e (patch) | |
| tree | fd0e53e5f51e6e03dda80d7aec6073f5cb694fd1 /arch | |
| parent | 4cee4798a304ee1ea579423ca048f16ceaccdfb5 (diff) | |
KVM: Ensure all vcpus are consistent with in-kernel irqchip settings
If some vcpus are created before KVM_CREATE_IRQCHIP, then
irqchip_in_kernel() and vcpu->arch.apic will be inconsistent, leading
to potential NULL pointer dereferences.
Fix by:
- ensuring that no vcpus are installed when KVM_CREATE_IRQCHIP is called
- ensuring that a vcpu has an apic if it is installed after KVM_CREATE_IRQCHIP
This is somewhat long winded because vcpu->arch.apic is created without
kvm->lock held.
Based on earlier patch by Michael Ellerman.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/ia64/kvm/kvm-ia64.c | 5 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 8 |
2 files changed, 13 insertions, 0 deletions
diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index d8ddbba6fe7d..f5104b7c52cd 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -1172,6 +1172,11 @@ out: #define PALE_RESET_ENTRY 0x80000000ffffffb0UL +bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu) +{ + return irqchip_in_kernel(vcpu->kcm) == (vcpu->arch.apic != NULL); +} + int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { struct kvm_vcpu *v; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 03a1fd47a6d3..9477dc6cccae 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3199,6 +3199,9 @@ long kvm_arch_vm_ioctl(struct file *filp, r = -EEXIST; if (kvm->arch.vpic) goto create_irqchip_unlock; + r = -EINVAL; + if (atomic_read(&kvm->online_vcpus)) + goto create_irqchip_unlock; r = -ENOMEM; vpic = kvm_create_pic(kvm); if (vpic) { @@ -6107,6 +6110,11 @@ void kvm_arch_check_processor_compat(void *rtn) kvm_x86_ops->check_processor_compatibility(rtn); } +bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu) +{ + return irqchip_in_kernel(vcpu->kvm) == (vcpu->arch.apic != NULL); +} + int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { struct page *page; |