Merge tag 'kvm-s390-next-20150209' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: fixes and features for kvm/next (3.20)

1. Fixes
- Fix user triggerable endless loop
- reenable LPP facility
- disable KVM compat ioctl on s390 (untested and broken)

2. cpu models for s390
- provide facilities and instruction blocking per VM
- add s390 specific vm attributes for setting values

3. crypto
- toleration patch for z13 support

4. add uuid and long name to /proc/sysinfo (stsi 322)
- patch Acked by Heiko Carstens (touches non-kvm s390 code)

Documentation/virtual/kvm/devices/vm.txt

···
 the maximum guest memory size. The limit will be rounded up to
 2048 MB, 4096 GB, 8192 TB respectively, as this limit is governed by
 the number of page table levels.
+
+2. GROUP: KVM_S390_VM_CPU_MODEL
+Architectures: s390
+
+2.1. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE (r/o)
+
+Allows user space to retrieve machine and kvm specific cpu related information:
+
+struct kvm_s390_vm_cpu_machine {
+       __u64 cpuid;           # CPUID of host
+       __u32 ibc;             # IBC level range offered by host
+       __u8  pad[4];
+       __u64 fac_mask[256];   # set of cpu facilities enabled by KVM
+       __u64 fac_list[256];   # set of cpu facilities offered by host
+}
+
+Parameters: address of buffer to store the machine related cpu data
+            of type struct kvm_s390_vm_cpu_machine*
+Returns:    -EFAULT if the given address is not accessible from kernel space
+	    -ENOMEM if not enough memory is available to process the ioctl
+	    0 in case of success
+
+2.2. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR (r/w)
+
+Allows user space to retrieve or request to change cpu related information for a vcpu:
+
+struct kvm_s390_vm_cpu_processor {
+       __u64 cpuid;           # CPUID currently (to be) used by this vcpu
+       __u16 ibc;             # IBC level currently (to be) used by this vcpu
+       __u8  pad[6];
+       __u64 fac_list[256];   # set of cpu facilities currently (to be) used
+                              # by this vcpu
+}
+
+KVM does not enforce or limit the cpu model data in any form. Take the information
+retrieved by means of KVM_S390_VM_CPU_MACHINE as hint for reasonable configuration
+setups. Instruction interceptions triggered by additionally set facilitiy bits that
+are not handled by KVM need to by imlemented in the VM driver code.
+
+Parameters: address of buffer to store/set the processor related cpu
+	    data of type struct kvm_s390_vm_cpu_processor*.
+Returns:    -EBUSY in case 1 or more vcpus are already activated (only in write case)
+	    -EFAULT if the given address is not accessible from kernel space
+	    -ENOMEM if not enough memory is available to process the ioctl
+	    0 in case of success

arch/s390/include/asm/kvm_host.h

···
 	atomic_t cpuflags;		/* 0x0000 */
 	__u32 : 1;			/* 0x0004 */
 	__u32 prefix : 18;
-	__u32 : 13;
+	__u32 : 1;
+	__u32 ibc : 12;
 	__u8	reserved08[4];		/* 0x0008 */
 #define PROG_IN_SIE (1<<0)
 	__u32	prog0c;			/* 0x000c */
···
 	__u64	tecmc;			/* 0x00e8 */
 	__u8	reservedf0[12];		/* 0x00f0 */
 #define CRYCB_FORMAT1 0x00000001
+#define CRYCB_FORMAT2 0x00000003
 	__u32	crycbd;			/* 0x00fc */
 	__u64	gcr[16];		/* 0x0100 */
 	__u64	gbea;			/* 0x0180 */
···
 #define MAX_S390_IO_ADAPTERS ((MAX_ISC + 1) * 8)
 #define MAX_S390_ADAPTER_MAPS 256
 
+/* maximum size of facilities and facility mask is 2k bytes */
+#define S390_ARCH_FAC_LIST_SIZE_BYTE (1<<11)
+#define S390_ARCH_FAC_LIST_SIZE_U64 \
+	(S390_ARCH_FAC_LIST_SIZE_BYTE / sizeof(u64))
+#define S390_ARCH_FAC_MASK_SIZE_BYTE S390_ARCH_FAC_LIST_SIZE_BYTE
+#define S390_ARCH_FAC_MASK_SIZE_U64 \
+	(S390_ARCH_FAC_MASK_SIZE_BYTE / sizeof(u64))
+
+struct s390_model_fac {
+	/* facilities used in SIE context */
+	__u64 sie[S390_ARCH_FAC_LIST_SIZE_U64];
+	/* subset enabled by kvm */
+	__u64 kvm[S390_ARCH_FAC_LIST_SIZE_U64];
+};
+
+struct kvm_s390_cpu_model {
+	struct s390_model_fac *fac;
+	struct cpuid cpu_id;
+	unsigned short ibc;
+};
+
 struct kvm_s390_crypto {
 	struct kvm_s390_crypto_cb *crycb;
 	__u32 crycbd;
···
 	__u8    reserved00[72];                 /* 0x0000 */
 	__u8    dea_wrapping_key_mask[24];      /* 0x0048 */
 	__u8    aes_wrapping_key_mask[32];      /* 0x0060 */
+	__u8    reserved80[128];                /* 0x0080 */
 };
 
 struct kvm_arch{
···
 	int ipte_lock_count;
 	struct mutex ipte_mutex;
 	spinlock_t start_stop_lock;
+	struct kvm_s390_cpu_model model;
 	struct kvm_s390_crypto crypto;
 	u64 epoch;
 };

arch/s390/include/asm/sysinfo.h

···
 #define __ASM_S390_SYSINFO_H
 
 #include <asm/bitsperlong.h>
+#include <linux/uuid.h>
 
 struct sysinfo_1_1_1 {
 	unsigned char p:1;
···
 		char name[8];
 		unsigned int caf;
 		char cpi[16];
-		char reserved_1[24];
-
+		char reserved_1[3];
+		char ext_name_encoding;
+		unsigned int reserved_2;
+		uuid_be uuid;
 	} vm[8];
-	char reserved_544[3552];
+	char reserved_3[1504];
+	char ext_names[8][256];
 };
 
 extern int topology_max_mnest;

arch/s390/include/uapi/asm/kvm.h

···
 #define KVM_S390_VM_MEM_CTRL		0
 #define KVM_S390_VM_TOD			1
 #define KVM_S390_VM_CRYPTO		2
+#define KVM_S390_VM_CPU_MODEL		3
 
 /* kvm attributes for mem_ctrl */
 #define KVM_S390_VM_MEM_ENABLE_CMMA	0
···
 /* kvm attributes for KVM_S390_VM_TOD */
 #define KVM_S390_VM_TOD_LOW		0
 #define KVM_S390_VM_TOD_HIGH		1
+
+/* kvm attributes for KVM_S390_VM_CPU_MODEL */
+/* processor related attributes are r/w */
+#define KVM_S390_VM_CPU_PROCESSOR	0
+struct kvm_s390_vm_cpu_processor {
+	__u64 cpuid;
+	__u16 ibc;
+	__u8  pad[6];
+	__u64 fac_list[256];
+};
+
+/* machine related attributes are r/o */
+#define KVM_S390_VM_CPU_MACHINE		1
+struct kvm_s390_vm_cpu_machine {
+	__u64 cpuid;
+	__u32 ibc;
+	__u8  pad[4];
+	__u64 fac_mask[256];
+	__u64 fac_list[256];
+};
 
 /* kvm attributes for crypto */
 #define KVM_S390_VM_CRYPTO_ENABLE_AES_KW	0

arch/s390/kernel/sysinfo.c

···
 	seq_printf(m, "LPAR CPUs Shared:     %d\n", info->cpus_shared);
 }
 
+static void print_ext_name(struct seq_file *m, int lvl,
+			   struct sysinfo_3_2_2 *info)
+{
+	if (info->vm[lvl].ext_name_encoding == 0)
+		return;
+	if (info->ext_names[lvl][0] == 0)
+		return;
+	switch (info->vm[lvl].ext_name_encoding) {
+	case 1: /* EBCDIC */
+		EBCASC(info->ext_names[lvl], sizeof(info->ext_names[lvl]));
+		break;
+	case 2:	/* UTF-8 */
+		break;
+	default:
+		return;
+	}
+	seq_printf(m, "VM%02d Extended Name:   %-.256s\n", lvl,
+		   info->ext_names[lvl]);
+}
+
+static void print_uuid(struct seq_file *m, int i, struct sysinfo_3_2_2 *info)
+{
+	if (!memcmp(&info->vm[i].uuid, &NULL_UUID_BE, sizeof(uuid_be)))
+		return;
+	seq_printf(m, "VM%02d UUID:            %pUb\n", i, &info->vm[i].uuid);
+}
+
 static void stsi_3_2_2(struct seq_file *m, struct sysinfo_3_2_2 *info)
 {
 	int i;
···
 		seq_printf(m, "VM%02d CPUs Configured: %d\n", i, info->vm[i].cpus_configured);
 		seq_printf(m, "VM%02d CPUs Standby:    %d\n", i, info->vm[i].cpus_standby);
 		seq_printf(m, "VM%02d CPUs Reserved:   %d\n", i, info->vm[i].cpus_reserved);
+		print_ext_name(m, i, info);
+		print_uuid(m, i, info);
 	}
 }
 

arch/s390/kvm/gaccess.c

···
 	union asce asce;
 
 	ctlreg0.val = vcpu->arch.sie_block->gcr[0];
-	edat1 = ctlreg0.edat && test_vfacility(8);
-	edat2 = edat1 && test_vfacility(78);
+	edat1 = ctlreg0.edat && test_kvm_facility(vcpu->kvm, 8);
+	edat2 = edat1 && test_kvm_facility(vcpu->kvm, 78);
 	asce.val = get_vcpu_asce(vcpu);
 	if (asce.r)
 		goto real_address;

arch/s390/kvm/interrupt.c

···
 		list_add_tail(&inti->list, &iter->list);
 	}
 	atomic_set(&fi->active, 1);
+	if (atomic_read(&kvm->online_vcpus) == 0)
+		goto unlock_fi;
 	sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
 	if (sigcpu == KVM_MAX_VCPUS) {
 		do {

arch/s390/kvm/kvm-s390.c

···
 #include <asm/pgtable.h>
 #include <asm/nmi.h>
 #include <asm/switch_to.h>
-#include <asm/facility.h>
 #include <asm/sclp.h>
 #include "kvm-s390.h"
 #include "gaccess.h"
···
 	{ NULL }
 };
 
-unsigned long *vfacilities;
-static struct gmap_notifier gmap_notifier;
+/* upper facilities limit for kvm */
+unsigned long kvm_s390_fac_list_mask[] = {
+	0xff82fffbf4fc2000UL,
+	0x005c000000000000UL,
+};
 
-/* test availability of vfacility */
-int test_vfacility(unsigned long nr)
+unsigned long kvm_s390_fac_list_mask_size(void)
 {
-	return __test_facility(nr, (void *) vfacilities);
+	BUILD_BUG_ON(ARRAY_SIZE(kvm_s390_fac_list_mask) > S390_ARCH_FAC_MASK_SIZE_U64);
+	return ARRAY_SIZE(kvm_s390_fac_list_mask);
 }
+
+static struct gmap_notifier gmap_notifier;
 
 /* Section: not file related */
 int kvm_arch_hardware_enable(void)
···
 	struct kvm_vcpu *vcpu;
 	int i;
 
-	if (!test_vfacility(76))
+	if (!test_kvm_facility(kvm, 76))
 		return -EINVAL;
 
 	mutex_lock(&kvm->lock);
···
 	return ret;
 }
 
+static int kvm_s390_set_processor(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	struct kvm_s390_vm_cpu_processor *proc;
+	int ret = 0;
+
+	mutex_lock(&kvm->lock);
+	if (atomic_read(&kvm->online_vcpus)) {
+		ret = -EBUSY;
+		goto out;
+	}
+	proc = kzalloc(sizeof(*proc), GFP_KERNEL);
+	if (!proc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	if (!copy_from_user(proc, (void __user *)attr->addr,
+			    sizeof(*proc))) {
+		memcpy(&kvm->arch.model.cpu_id, &proc->cpuid,
+		       sizeof(struct cpuid));
+		kvm->arch.model.ibc = proc->ibc;
+		memcpy(kvm->arch.model.fac->kvm, proc->fac_list,
+		       S390_ARCH_FAC_LIST_SIZE_BYTE);
+	} else
+		ret = -EFAULT;
+	kfree(proc);
+out:
+	mutex_unlock(&kvm->lock);
+	return ret;
+}
+
+static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	int ret = -ENXIO;
+
+	switch (attr->attr) {
+	case KVM_S390_VM_CPU_PROCESSOR:
+		ret = kvm_s390_set_processor(kvm, attr);
+		break;
+	}
+	return ret;
+}
+
+static int kvm_s390_get_processor(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	struct kvm_s390_vm_cpu_processor *proc;
+	int ret = 0;
+
+	proc = kzalloc(sizeof(*proc), GFP_KERNEL);
+	if (!proc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	memcpy(&proc->cpuid, &kvm->arch.model.cpu_id, sizeof(struct cpuid));
+	proc->ibc = kvm->arch.model.ibc;
+	memcpy(&proc->fac_list, kvm->arch.model.fac->kvm, S390_ARCH_FAC_LIST_SIZE_BYTE);
+	if (copy_to_user((void __user *)attr->addr, proc, sizeof(*proc)))
+		ret = -EFAULT;
+	kfree(proc);
+out:
+	return ret;
+}
+
+static int kvm_s390_get_machine(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	struct kvm_s390_vm_cpu_machine *mach;
+	int ret = 0;
+
+	mach = kzalloc(sizeof(*mach), GFP_KERNEL);
+	if (!mach) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	get_cpu_id((struct cpuid *) &mach->cpuid);
+	mach->ibc = sclp_get_ibc();
+	memcpy(&mach->fac_mask, kvm_s390_fac_list_mask,
+	       kvm_s390_fac_list_mask_size() * sizeof(u64));
+	memcpy((unsigned long *)&mach->fac_list, S390_lowcore.stfle_fac_list,
+	       S390_ARCH_FAC_LIST_SIZE_U64);
+	if (copy_to_user((void __user *)attr->addr, mach, sizeof(*mach)))
+		ret = -EFAULT;
+	kfree(mach);
+out:
+	return ret;
+}
+
+static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	int ret = -ENXIO;
+
+	switch (attr->attr) {
+	case KVM_S390_VM_CPU_PROCESSOR:
+		ret = kvm_s390_get_processor(kvm, attr);
+		break;
+	case KVM_S390_VM_CPU_MACHINE:
+		ret = kvm_s390_get_machine(kvm, attr);
+		break;
+	}
+	return ret;
+}
+
 static int kvm_s390_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
 {
 	int ret;
···
 		break;
 	case KVM_S390_VM_TOD:
 		ret = kvm_s390_set_tod(kvm, attr);
+		break;
+	case KVM_S390_VM_CPU_MODEL:
+		ret = kvm_s390_set_cpu_model(kvm, attr);
 		break;
 	case KVM_S390_VM_CRYPTO:
 		ret = kvm_s390_vm_set_crypto(kvm, attr);
···
 		break;
 	case KVM_S390_VM_TOD:
 		ret = kvm_s390_get_tod(kvm, attr);
+		break;
+	case KVM_S390_VM_CPU_MODEL:
+		ret = kvm_s390_get_cpu_model(kvm, attr);
 		break;
 	default:
 		ret = -ENXIO;
···
 		switch (attr->attr) {
 		case KVM_S390_VM_TOD_LOW:
 		case KVM_S390_VM_TOD_HIGH:
+			ret = 0;
+			break;
+		default:
+			ret = -ENXIO;
+			break;
+		}
+		break;
+	case KVM_S390_VM_CPU_MODEL:
+		switch (attr->attr) {
+		case KVM_S390_VM_CPU_PROCESSOR:
+		case KVM_S390_VM_CPU_MACHINE:
 			ret = 0;
 			break;
 		default:
···
 	return r;
 }
 
+static int kvm_s390_query_ap_config(u8 *config)
+{
+	u32 fcn_code = 0x04000000UL;
+	u32 cc;
+
+	asm volatile(
+		"lgr 0,%1\n"
+		"lgr 2,%2\n"
+		".long 0xb2af0000\n"		/* PQAP(QCI) */
+		"ipm %0\n"
+		"srl %0,28\n"
+		: "=r" (cc)
+		: "r" (fcn_code), "r" (config)
+		: "cc", "0", "2", "memory"
+	);
+
+	return cc;
+}
+
+static int kvm_s390_apxa_installed(void)
+{
+	u8 config[128];
+	int cc;
+
+	if (test_facility(2) && test_facility(12)) {
+		cc = kvm_s390_query_ap_config(config);
+
+		if (cc)
+			pr_err("PQAP(QCI) failed with cc=%d", cc);
+		else
+			return config[0] & 0x40;
+	}
+
+	return 0;
+}
+
+static void kvm_s390_set_crycb_format(struct kvm *kvm)
+{
+	kvm->arch.crypto.crycbd = (__u32)(unsigned long) kvm->arch.crypto.crycb;
+
+	if (kvm_s390_apxa_installed())
+		kvm->arch.crypto.crycbd |= CRYCB_FORMAT2;
+	else
+		kvm->arch.crypto.crycbd |= CRYCB_FORMAT1;
+}
+
+static void kvm_s390_get_cpu_id(struct cpuid *cpu_id)
+{
+	get_cpu_id(cpu_id);
+	cpu_id->version = 0xff;
+}
+
 static int kvm_s390_crypto_init(struct kvm *kvm)
 {
-	if (!test_vfacility(76))
+	if (!test_kvm_facility(kvm, 76))
 		return 0;
 
 	kvm->arch.crypto.crycb = kzalloc(sizeof(*kvm->arch.crypto.crycb),
···
 	if (!kvm->arch.crypto.crycb)
 		return -ENOMEM;
 
-	kvm->arch.crypto.crycbd = (__u32) (unsigned long) kvm->arch.crypto.crycb |
-				  CRYCB_FORMAT1;
+	kvm_s390_set_crycb_format(kvm);
 
 	/* Disable AES/DEA protected key functions by default */
 	kvm->arch.crypto.aes_kw = 0;
···
 
 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 {
-	int rc;
+	int i, rc;
 	char debug_name[16];
 	static unsigned long sca_offset;
 
···
 	if (!kvm->arch.dbf)
 		goto out_nodbf;
 
+	/*
+	 * The architectural maximum amount of facilities is 16 kbit. To store
+	 * this amount, 2 kbyte of memory is required. Thus we need a full
+	 * page to hold the active copy (arch.model.fac->sie) and the current
+	 * facilities set (arch.model.fac->kvm). Its address size has to be
+	 * 31 bits and word aligned.
+	 */
+	kvm->arch.model.fac =
+		(struct s390_model_fac *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	if (!kvm->arch.model.fac)
+		goto out_nofac;
+
+	memcpy(kvm->arch.model.fac->kvm, S390_lowcore.stfle_fac_list,
+	       S390_ARCH_FAC_LIST_SIZE_U64);
+
+	/*
+	 * If this KVM host runs *not* in a LPAR, relax the facility bits
+	 * of the kvm facility mask by all missing facilities. This will allow
+	 * to determine the right CPU model by means of the remaining facilities.
+	 * Live guest migration must prohibit the migration of KVMs running in
+	 * a LPAR to non LPAR hosts.
+	 */
+	if (!MACHINE_IS_LPAR)
+		for (i = 0; i < kvm_s390_fac_list_mask_size(); i++)
+			kvm_s390_fac_list_mask[i] &= kvm->arch.model.fac->kvm[i];
+
+	/*
+	 * Apply the kvm facility mask to limit the kvm supported/tolerated
+	 * facility list.
+	 */
+	for (i = 0; i < S390_ARCH_FAC_LIST_SIZE_U64; i++) {
+		if (i < kvm_s390_fac_list_mask_size())
+			kvm->arch.model.fac->kvm[i] &= kvm_s390_fac_list_mask[i];
+		else
+			kvm->arch.model.fac->kvm[i] = 0UL;
+	}
+
+	kvm_s390_get_cpu_id(&kvm->arch.model.cpu_id);
+	kvm->arch.model.ibc = sclp_get_ibc() & 0x0fff;
+
 	if (kvm_s390_crypto_init(kvm) < 0)
 		goto out_crypto;
 
···
 out_nogmap:
 	kfree(kvm->arch.crypto.crycb);
 out_crypto:
+	free_page((unsigned long)kvm->arch.model.fac);
+out_nofac:
 	debug_unregister(kvm->arch.dbf);
 out_nodbf:
 	free_page((unsigned long)(kvm->arch.sca));
···
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
 	kvm_free_vcpus(kvm);
+	free_page((unsigned long)kvm->arch.model.fac);
 	free_page((unsigned long)(kvm->arch.sca));
 	debug_unregister(kvm->arch.dbf);
 	kfree(kvm->arch.crypto.crycb);
···
 
 static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
 {
-	if (!test_vfacility(76))
+	if (!test_kvm_facility(vcpu->kvm, 76))
 		return;
 
 	vcpu->arch.sie_block->ecb3 &= ~(ECB3_AES | ECB3_DEA);
···
 						    CPUSTAT_STOPPED |
 						    CPUSTAT_GED);
 	vcpu->arch.sie_block->ecb   = 6;
-	if (test_vfacility(50) && test_vfacility(73))
+	if (test_kvm_facility(vcpu->kvm, 50) && test_kvm_facility(vcpu->kvm, 73))
 		vcpu->arch.sie_block->ecb |= 0x10;
 
 	vcpu->arch.sie_block->ecb2  = 8;
···
 		vcpu->arch.sie_block->eca |= 1;
 	if (sclp_has_sigpif())
 		vcpu->arch.sie_block->eca |= 0x10000000U;
-	vcpu->arch.sie_block->fac   = (int) (long) vfacilities;
 	vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE |
 				      ICTL_TPROT;
 
···
 	}
 	hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
-	get_cpu_id(&vcpu->arch.cpu_id);
-	vcpu->arch.cpu_id.version = 0xff;
+
+	mutex_lock(&vcpu->kvm->lock);
+	vcpu->arch.cpu_id = vcpu->kvm->arch.model.cpu_id;
+	memcpy(vcpu->kvm->arch.model.fac->sie, vcpu->kvm->arch.model.fac->kvm,
+	       S390_ARCH_FAC_LIST_SIZE_BYTE);
+	vcpu->arch.sie_block->ibc = vcpu->kvm->arch.model.ibc;
+	mutex_unlock(&vcpu->kvm->lock);
 
 	kvm_s390_vcpu_crypto_setup(vcpu);
 
···
 		vcpu->arch.sie_block->scaol = (__u32)(__u64)kvm->arch.sca;
 		set_bit(63 - id, (unsigned long *) &kvm->arch.sca->mcn);
 	}
+	vcpu->arch.sie_block->fac = (int) (long) kvm->arch.model.fac->sie;
 
 	spin_lock_init(&vcpu->arch.local_int.lock);
 	vcpu->arch.local_int.float_int = &kvm->arch.float_int;
···
 
 static int __init kvm_s390_init(void)
 {
-	int ret;
-	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
-	if (ret)
-		return ret;
-
-	/*
-	 * guests can ask for up to 255+1 double words, we need a full page
-	 * to hold the maximum amount of facilities. On the other hand, we
-	 * only set facilities that are known to work in KVM.
-	 */
-	vfacilities = (unsigned long *) get_zeroed_page(GFP_KERNEL|GFP_DMA);
-	if (!vfacilities) {
-		kvm_exit();
-		return -ENOMEM;
-	}
-	memcpy(vfacilities, S390_lowcore.stfle_fac_list, 16);
-	vfacilities[0] &= 0xff82fffbf47c2000UL;
-	vfacilities[1] &= 0x005c000000000000UL;
-	return 0;
+	return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
 }
 
 static void __exit kvm_s390_exit(void)
 {
-	free_page((unsigned long) vfacilities);
 	kvm_exit();
 }
 

arch/s390/kvm/kvm-s390.h

···
 #include <linux/hrtimer.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
+#include <asm/facility.h>
 
 typedef int (*intercept_handler_t)(struct kvm_vcpu *vcpu);
-
-/* declare vfacilities extern */
-extern unsigned long *vfacilities;
 
 /* Transactional Memory Execution related macros */
 #define IS_TE_ENABLED(vcpu)	((vcpu->arch.sie_block->ecb & 0x10))
···
 	vcpu->arch.sie_block->gpsw.mask |= cc << 44;
 }
 
+/* test availability of facility in a kvm intance */
+static inline int test_kvm_facility(struct kvm *kvm, unsigned long nr)
+{
+	return __test_facility(nr, kvm->arch.model.fac->kvm);
+}
+
 /* are cpu states controlled by user space */
 static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm)
 {
···
 void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu);
 /* is cmma enabled */
 bool kvm_s390_cmma_enabled(struct kvm *kvm);
-int test_vfacility(unsigned long nr);
+unsigned long kvm_s390_fac_list_mask_size(void);
+extern unsigned long kvm_s390_fac_list_mask[];
 
 /* implemented in diag.c */
 int kvm_s390_handle_diag(struct kvm_vcpu *vcpu);

arch/s390/kvm/priv.c

···
 static int handle_stfl(struct kvm_vcpu *vcpu)
 {
 	int rc;
+	unsigned int fac;
 
 	vcpu->stat.instruction_stfl++;
 
 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 		return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
 
+	/*
+	 * We need to shift the lower 32 facility bits (bit 0-31) from a u64
+	 * into a u32 memory representation. They will remain bits 0-31.
+	 */
+	fac = *vcpu->kvm->arch.model.fac->sie >> 32;
 	rc = write_guest_lc(vcpu, offsetof(struct _lowcore, stfl_fac_list),
-			    vfacilities, 4);
+			    &fac, sizeof(fac));
 	if (rc)
 		return rc;
-	VCPU_EVENT(vcpu, 5, "store facility list value %x",
-		   *(unsigned int *) vfacilities);
-	trace_kvm_s390_handle_stfl(vcpu, *(unsigned int *) vfacilities);
+	VCPU_EVENT(vcpu, 5, "store facility list value %x", fac);
+	trace_kvm_s390_handle_stfl(vcpu, fac);
 	return 0;
 }
 

virt/kvm/Kconfig

···
 
 config KVM_GENERIC_DIRTYLOG_READ_PROTECT
        bool
+
+config KVM_COMPAT
+       def_bool y
+       depends on COMPAT && !S390

virt/kvm/kvm_main.c

···
 
 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
 			   unsigned long arg);
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_KVM_COMPAT
 static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
 				  unsigned long arg);
 #endif
···
 static struct file_operations kvm_vcpu_fops = {
 	.release        = kvm_vcpu_release,
 	.unlocked_ioctl = kvm_vcpu_ioctl,
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_KVM_COMPAT
 	.compat_ioctl   = kvm_vcpu_compat_ioctl,
 #endif
 	.mmap           = kvm_vcpu_mmap,
···
 	return r;
 }
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_KVM_COMPAT
 static long kvm_vcpu_compat_ioctl(struct file *filp,
 				  unsigned int ioctl, unsigned long arg)
 {
···
 
 static const struct file_operations kvm_device_fops = {
 	.unlocked_ioctl = kvm_device_ioctl,
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_KVM_COMPAT
 	.compat_ioctl = kvm_device_ioctl,
 #endif
 	.release = kvm_device_release,
···
 	return r;
 }
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_KVM_COMPAT
 struct compat_kvm_dirty_log {
 	__u32 slot;
 	__u32 padding1;
···
 static struct file_operations kvm_vm_fops = {
 	.release        = kvm_vm_release,
 	.unlocked_ioctl = kvm_vm_ioctl,
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_KVM_COMPAT
 	.compat_ioctl   = kvm_vm_compat_ioctl,
 #endif
 	.llseek		= noop_llseek,