kvm: Convert kvm_lock to a mutex

commit 0d9ce162cf46c99628cc5da9510b959c7976735b upstream.

It doesn't seem as if there is any particular need for kvm_lock to be a
spinlock, so convert the lock to a mutex so that sleepable functions (in
particular cond_resched()) can be called while holding it.

Signed-off-by: Junaid Shahid <junaids@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 15 insertions, 15 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1ba7c312d26a..345f6cf36043 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -92,7 +92,7 @@ EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
  *	kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  */
 
-DEFINE_SPINLOCK(kvm_lock);
+DEFINE_MUTEX(kvm_lock);
 static DEFINE_RAW_SPINLOCK(kvm_count_lock);
 LIST_HEAD(vm_list);
 
@@ -668,9 +668,9 @@ static struct kvm *kvm_create_vm(unsigned long type)
 	if (r)
 		goto out_err;
 
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	list_add(&kvm->vm_list, &vm_list);
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 
 	preempt_notifier_inc();
 
@@ -716,9 +716,9 @@ static void kvm_destroy_vm(struct kvm *kvm)
 	kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
 	kvm_destroy_vm_debugfs(kvm);
 	kvm_arch_sync_events(kvm);
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	list_del(&kvm->vm_list);
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 	kvm_free_irq_routing(kvm);
 	for (i = 0; i < KVM_NR_BUSES; i++) {
 		struct kvm_io_bus *bus = kvm_get_bus(kvm, i);
@@ -3830,13 +3830,13 @@ static int vm_stat_get(void *_offset, u64 *val)
 	u64 tmp_val;
 
 	*val = 0;
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
 		stat_tmp.kvm = kvm;
 		vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
 		*val += tmp_val;
 	}
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 	return 0;
 }
 
@@ -3849,12 +3849,12 @@ static int vm_stat_clear(void *_offset, u64 val)
 	if (val)
 		return -EINVAL;
 
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
 		stat_tmp.kvm = kvm;
 		vm_stat_clear_per_vm((void *)&stat_tmp, 0);
 	}
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 
 	return 0;
 }
@@ -3869,13 +3869,13 @@ static int vcpu_stat_get(void *_offset, u64 *val)
 	u64 tmp_val;
 
 	*val = 0;
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
 		stat_tmp.kvm = kvm;
 		vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
 		*val += tmp_val;
 	}
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 	return 0;
 }
 
@@ -3888,12 +3888,12 @@ static int vcpu_stat_clear(void *_offset, u64 val)
 	if (val)
 		return -EINVAL;
 
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
 		stat_tmp.kvm = kvm;
 		vcpu_stat_clear_per_vm((void *)&stat_tmp, 0);
 	}
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 
 	return 0;
 }
@@ -3914,7 +3914,7 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm)
 	if (!kvm_dev.this_device || !kvm)
 		return;
 
-	spin_lock(&kvm_lock);
+	mutex_lock(&kvm_lock);
 	if (type == KVM_EVENT_CREATE_VM) {
 		kvm_createvm_count++;
 		kvm_active_vms++;
@@ -3923,7 +3923,7 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm)
 	}
 	created = kvm_createvm_count;
 	active = kvm_active_vms;
-	spin_unlock(&kvm_lock);
+	mutex_unlock(&kvm_lock);
 
 	env = kzalloc(sizeof(*env), GFP_KERNEL);
 	if (!env)