1 files changed, 32 insertions, 12 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 0a01744cbdd9..e519860c6031 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -633,7 +633,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 		vcpu->arch.sie_block->ecb |= 0x10;
 
 	vcpu->arch.sie_block->ecb2  = 8;
-	vcpu->arch.sie_block->eca   = 0xC1002000U;
+	vcpu->arch.sie_block->eca   = 0xD1002000U;
 	if (sclp_has_siif())
 		vcpu->arch.sie_block->eca |= 1;
 	vcpu->arch.sie_block->fac   = (int) (long) vfacilities;
@@ -753,7 +753,7 @@ static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address)
 
 	kvm_for_each_vcpu(i, vcpu, kvm) {
 		/* match against both prefix pages */
-		if (vcpu->arch.sie_block->prefix == (address & ~0x1000UL)) {
+		if (kvm_s390_get_prefix(vcpu) == (address & ~0x1000UL)) {
 			VCPU_EVENT(vcpu, 2, "gmap notifier for %lx", address);
 			kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
 			exit_sie_sync(vcpu);
@@ -1017,7 +1017,7 @@ retry:
 	if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) {
 		int rc;
 		rc = gmap_ipte_notify(vcpu->arch.gmap,
-				      vcpu->arch.sie_block->prefix,
+				      kvm_s390_get_prefix(vcpu),
 				      PAGE_SIZE * 2);
 		if (rc)
 			return rc;
@@ -1045,15 +1045,30 @@ retry:
 	return 0;
 }
 
-static long kvm_arch_fault_in_sync(struct kvm_vcpu *vcpu)
+/**
+ * kvm_arch_fault_in_page - fault-in guest page if necessary
+ * @vcpu: The corresponding virtual cpu
+ * @gpa: Guest physical address
+ * @writable: Whether the page should be writable or not
+ *
+ * Make sure that a guest page has been faulted-in on the host.
+ *
+ * Return: Zero on success, negative error code otherwise.
+ */
+long kvm_arch_fault_in_page(struct kvm_vcpu *vcpu, gpa_t gpa, int writable)
 {
-	long rc;
-	hva_t fault = gmap_fault(current->thread.gmap_addr, vcpu->arch.gmap);
 	struct mm_struct *mm = current->mm;
+	hva_t hva;
+	long rc;
+
+	hva = gmap_fault(gpa, vcpu->arch.gmap);
+	if (IS_ERR_VALUE(hva))
+		return (long)hva;
 	down_read(&mm->mmap_sem);
-	rc = get_user_pages(current, mm, fault, 1, 1, 0, NULL, NULL);
+	rc = get_user_pages(current, mm, hva, 1, writable, 0, NULL, NULL);
 	up_read(&mm->mmap_sem);
-	return rc;
+
+	return rc < 0 ? rc : 0;
 }
 
 static void __kvm_inject_pfault_token(struct kvm_vcpu *vcpu, bool start_token,
@@ -1191,9 +1206,12 @@ static int vcpu_post_run(struct kvm_vcpu *vcpu, int exit_reason)
 	} else if (current->thread.gmap_pfault) {
 		trace_kvm_s390_major_guest_pfault(vcpu);
 		current->thread.gmap_pfault = 0;
-		if (kvm_arch_setup_async_pf(vcpu) ||
-		    (kvm_arch_fault_in_sync(vcpu) >= 0))
+		if (kvm_arch_setup_async_pf(vcpu)) {
 			rc = 0;
+		} else {
+			gpa_t gpa = current->thread.gmap_addr;
+			rc = kvm_arch_fault_in_page(vcpu, gpa, 1);
+		}
 	}
 
 	if (rc == -1) {
@@ -1320,7 +1338,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
 	kvm_run->psw_mask     = vcpu->arch.sie_block->gpsw.mask;
 	kvm_run->psw_addr     = vcpu->arch.sie_block->gpsw.addr;
-	kvm_run->s.regs.prefix = vcpu->arch.sie_block->prefix;
+	kvm_run->s.regs.prefix = kvm_s390_get_prefix(vcpu);
 	memcpy(&kvm_run->s.regs.crs, &vcpu->arch.sie_block->gcr, 128);
 
 	if (vcpu->sigset_active)
@@ -1339,6 +1357,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long gpa)
 {
 	unsigned char archmode = 1;
+	unsigned int px;
 	u64 clkcomp;
 	int rc;
 
@@ -1357,8 +1376,9 @@ int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long gpa)
 			      vcpu->run->s.regs.gprs, 128);
 	rc |= write_guest_abs(vcpu, gpa + offsetof(struct save_area, psw),
 			      &vcpu->arch.sie_block->gpsw, 16);
+	px = kvm_s390_get_prefix(vcpu);
 	rc |= write_guest_abs(vcpu, gpa + offsetof(struct save_area, pref_reg),
-			      &vcpu->arch.sie_block->prefix, 4);
+			      &px, 4);
 	rc |= write_guest_abs(vcpu,
 			      gpa + offsetof(struct save_area, fp_ctrl_reg),
 			      &vcpu->arch.guest_fpregs.fpc, 4);