Merge tag 'kvm-x86-dirty_ring-6.17' of https://github.com/kvm-x86/linux into HEAD

KVM Dirty Ring changes for 6.17

Fix issues with dirty ring harvesting where KVM doesn't bound the processing
of entries in any way, which allows userspace to keep KVM in a tight loop
indefinitely.  Clean up code and comments along the way.

1 files changed, 5 insertions, 13 deletions

diff --git a/include/linux/kvm_dirty_ring.h b/include/linux/kvm_dirty_ring.h
index da4d9b5f58f1..eb10d87adf7d 100644
--- a/include/linux/kvm_dirty_ring.h
+++ b/include/linux/kvm_dirty_ring.h
@@ -49,9 +49,10 @@ static inline int kvm_dirty_ring_alloc(struct kvm *kvm, struct kvm_dirty_ring *r
 }
 
 static inline int kvm_dirty_ring_reset(struct kvm *kvm,
-				       struct kvm_dirty_ring *ring)
+				       struct kvm_dirty_ring *ring,
+				       int *nr_entries_reset)
 {
-	return 0;
+	return -ENOENT;
 }
 
 static inline void kvm_dirty_ring_push(struct kvm_vcpu *vcpu,
@@ -77,17 +78,8 @@ bool kvm_arch_allow_write_without_running_vcpu(struct kvm *kvm);
 u32 kvm_dirty_ring_get_rsvd_entries(struct kvm *kvm);
 int kvm_dirty_ring_alloc(struct kvm *kvm, struct kvm_dirty_ring *ring,
 			 int index, u32 size);
-
-/*
- * called with kvm->slots_lock held, returns the number of
- * processed pages.
- */
-int kvm_dirty_ring_reset(struct kvm *kvm, struct kvm_dirty_ring *ring);
-
-/*
- * returns =0: successfully pushed
- *         <0: unable to push, need to wait
- */
+int kvm_dirty_ring_reset(struct kvm *kvm, struct kvm_dirty_ring *ring,
+			 int *nr_entries_reset);
 void kvm_dirty_ring_push(struct kvm_vcpu *vcpu, u32 slot, u64 offset);
 
 bool kvm_dirty_ring_check_request(struct kvm_vcpu *vcpu);