1 files changed, 52 insertions, 11 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index f4d56e9939c9..10bccd1f8aee 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -15,6 +15,7 @@
 #include <linux/compiler.h>
 #include <linux/err.h>
 #include <linux/fs.h>
+#include <linux/hrtimer.h>
 #include <linux/init.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
@@ -195,6 +196,10 @@ out_nokvm:
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
         VCPU_EVENT(vcpu, 3, "%s", "free cpu");
+        if (vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda ==
+                (__u64) vcpu->arch.sie_block)
+                vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda = 0;
+        smp_mb();
         free_page((unsigned long)(vcpu->arch.sie_block));
         kvm_vcpu_uninit(vcpu);
         kfree(vcpu);
@@ -283,8 +288,10 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
         vcpu->arch.sie_block->gmsor = vcpu->kvm->arch.guest_origin;
         vcpu->arch.sie_block->ecb   = 2;
         vcpu->arch.sie_block->eca   = 0xC1002001U;
-        setup_timer(&vcpu->arch.ckc_timer, kvm_s390_idle_wakeup,
-                 (unsigned long) vcpu);
+        hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
+        tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet,
+                     (unsigned long) vcpu);
+        vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
         get_cpu_id(&vcpu->arch.cpu_id);
         vcpu->arch.cpu_id.version = 0xff;
         return 0;
@@ -307,19 +314,21 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
 
         vcpu->arch.sie_block->icpua = id;
         BUG_ON(!kvm->arch.sca);
-        BUG_ON(kvm->arch.sca->cpu[id].sda);
-        kvm->arch.sca->cpu[id].sda = (__u64) vcpu->arch.sie_block;
+        if (!kvm->arch.sca->cpu[id].sda)
+                kvm->arch.sca->cpu[id].sda = (__u64) vcpu->arch.sie_block;
+        else
+                BUG_ON(!kvm->vcpus[id]); /* vcpu does already exist */
         vcpu->arch.sie_block->scaoh = (__u32)(((__u64)kvm->arch.sca) >> 32);
         vcpu->arch.sie_block->scaol = (__u32)(__u64)kvm->arch.sca;
 
         spin_lock_init(&vcpu->arch.local_int.lock);
         INIT_LIST_HEAD(&vcpu->arch.local_int.list);
         vcpu->arch.local_int.float_int = &kvm->arch.float_int;
-        spin_lock_bh(&kvm->arch.float_int.lock);
+        spin_lock(&kvm->arch.float_int.lock);
         kvm->arch.float_int.local_int[id] = &vcpu->arch.local_int;
         init_waitqueue_head(&vcpu->arch.local_int.wq);
         vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags;
-        spin_unlock_bh(&kvm->arch.float_int.lock);
+        spin_unlock(&kvm->arch.float_int.lock);
 
         rc = kvm_vcpu_init(vcpu, kvm, id);
         if (rc)
@@ -478,6 +487,12 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
         vcpu_load(vcpu);
 
+        /* verify, that memory has been registered */
+        if (!vcpu->kvm->arch.guest_memsize) {
+                vcpu_put(vcpu);
+                return -EINVAL;
+        }
+
         if (vcpu->sigset_active)
                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 
@@ -657,6 +672,8 @@ 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.
@@ -664,7 +681,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
            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 +693,39 @@ 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)