Commit 8e2207cd authored Jan 15, 2015 by David Hildenbrand Committed by Christian Borntraeger Feb 09, 2015

KVM: s390: floating irqs: fix user triggerable endless loop



If a vm with no VCPUs is created, the injection of a floating irq
leads to an endless loop in the kernel.

Let's skip the search for a destination VCPU for a floating irq if no
VCPUs were created.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

parent f7819512

arch/s390/kvm/interrupt.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1244,6 +1244,8 @@ static int __inject_vm(struct kvm kvm, struct kvm_s390_interrupt_info inti)
		list_add_tail(&inti->list, &iter->list);
		}
		atomic_set(&fi->active, 1);
		if (atomic_read(&kvm->online_vcpus) == 0)
		goto unlock_fi;
		sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
		if (sigcpu == KVM_MAX_VCPUS) {
		do {