[PATCH 1/3] KVM: Take missing slots_lock for kvm_io_bus_unregister_dev()

[Takuya Yoshikawa <takuya.yoshikawa@gmail.com>]

From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>

In KVM_CREATE_IRQCHIP, kvm_io_bus_unregister_dev() is called without taking
slots_lock in the error handling path.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
---
 arch/ia64/kvm/kvm-ia64.c |    2 ++
 arch/x86/kvm/x86.c       |    4 ++++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index 48a48bd..70d224d 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -951,7 +951,9 @@ long kvm_arch_vm_ioctl(struct file *filp,
 			goto out;
 		r = kvm_setup_default_irq_routing(kvm);
 		if (r) {
+			mutex_lock(&kvm->slots_lock);
 			kvm_ioapic_destroy(kvm);
+			mutex_unlock(&kvm->slots_lock);
 			goto out;
 		}
 		break;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8d76150..3113aaf 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3308,8 +3308,10 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		if (vpic) {
 			r = kvm_ioapic_init(kvm);
 			if (r) {
+				mutex_lock(&kvm->slots_lock);
 				kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS,
 							  &vpic->dev);
+				mutex_unlock(&kvm->slots_lock);
 				kfree(vpic);
 				goto create_irqchip_unlock;
 			}
@@ -3320,10 +3322,12 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		smp_wmb();
 		r = kvm_setup_default_irq_routing(kvm);
 		if (r) {
+			mutex_lock(&kvm->slots_lock);
 			mutex_lock(&kvm->irq_lock);
 			kvm_ioapic_destroy(kvm);
 			kvm_destroy_pic(kvm);
 			mutex_unlock(&kvm->irq_lock);
+			mutex_unlock(&kvm->slots_lock);
 		}
 	create_irqchip_unlock:
 		mutex_unlock(&kvm->lock);
-- 
1.7.1