---

yaml
---
r: 146589
b: refs/heads/master
c: 2668dab
h: refs/heads/master
i:
  146587: b610242
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 58f8ac279a8c46eb0a3193edd521ed2e41c4f914
+refs/heads/master: 2668dab794272f0898491acaf1e77e9a005abc0f

trunk/arch/s390/kvm/kvm-s390.c

@@ -657,14 +657,16 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
 				struct kvm_memory_slot old,
 				int user_alloc)
 {
+	int i;
+
 	/* A few sanity checks. We can have exactly one memory slot which has
 	   to start at guest virtual zero and which has to be located at a
 	   page boundary in userland and which has to end at a page boundary.
 	   The memory in userland is ok to be fragmented into various different
 	   vmas. It is okay to mmap() and munmap() stuff in this slot after
 	   doing this call at any time */
 
-	if (mem->slot)
+	if (mem->slot || kvm->arch.guest_memsize)
 		return -EINVAL;
 
 	if (mem->guest_phys_addr)
@@ -676,15 +678,39 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
 	if (mem->memory_size & (PAGE_SIZE - 1))
 		return -EINVAL;
 
+	if (!user_alloc)
+		return -EINVAL;
+
+	/* lock all vcpus */
+	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+		if (!kvm->vcpus[i])
+			continue;
+		if (!mutex_trylock(&kvm->vcpus[i]->mutex))
+			goto fail_out;
+	}
+
 	kvm->arch.guest_origin = mem->userspace_addr;
 	kvm->arch.guest_memsize = mem->memory_size;
 
-	/* FIXME: we do want to interrupt running CPUs and update their memory
-	   configuration now to avoid race conditions. But hey, changing the
-	   memory layout while virtual CPUs are running is usually bad
-	   programming practice. */
+	/* update sie control blocks, and unlock all vcpus */
+	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+		if (kvm->vcpus[i]) {
+			kvm->vcpus[i]->arch.sie_block->gmsor =
+				kvm->arch.guest_origin;
+			kvm->vcpus[i]->arch.sie_block->gmslm =
+				kvm->arch.guest_memsize +
+				kvm->arch.guest_origin +
+				VIRTIODESCSPACE - 1ul;
+			mutex_unlock(&kvm->vcpus[i]->mutex);
+		}
+	}
 
 	return 0;
+
+fail_out:
+	for (; i >= 0; i--)
+		mutex_unlock(&kvm->vcpus[i]->mutex);
+	return -EINVAL;
 }
 
 void kvm_arch_flush_shadow(struct kvm *kvm)