diff options
author | Avi Kivity <avi@redhat.com> | 2012-03-05 14:23:29 +0200 |
---|---|---|
committer | Paul Gortmaker <paul.gortmaker@windriver.com> | 2012-08-17 15:35:04 -0400 |
commit | b7dbece7db7a9a7400ab5786c3bd74f4a604500b (patch) | |
tree | 0893bf832314c4e13fe84f1fe6091c6a847d24c9 /arch/x86 | |
parent | 46d9757e3c6e018f9b95d93752b5051d6100bb06 (diff) |
KVM: Ensure all vcpus are consistent with in-kernel irqchip settings
commit 3e515705a1f46beb1c942bb8043c16f8ac7b1e9e upstream.
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>
[PG: in .34 label "unlock_vcpu_destroy" is just "vcpu_destroy"]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/kvm/x86.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8ced130d8c0..c1e586d82c1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2764,6 +2764,9 @@ 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) { @@ -5586,6 +5589,11 @@ 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; |