1 files changed, 626 insertions, 0 deletions

diff --git a/arch/s390/kvm/guestdbg.c b/arch/s390/kvm/guestdbg.c
new file mode 100644
index 000000000..394a5f538
--- /dev/null
+++ b/arch/s390/kvm/guestdbg.c
@@ -0,0 +1,626 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kvm guest debug support
+ *
+ * Copyright IBM Corp. 2014
+ *
+ *    Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com>
+ */
+#include <linux/kvm_host.h>
+#include <linux/errno.h>
+#include "kvm-s390.h"
+#include "gaccess.h"
+
+/*
+ * Extends the address range given by *start and *stop to include the address
+ * range starting with estart and the length len. Takes care of overflowing
+ * intervals and tries to minimize the overall interval size.
+ */
+static void extend_address_range(u64 *start, u64 *stop, u64 estart, int len)
+{
+	u64 estop;
+
+	if (len > 0)
+		len--;
+	else
+		len = 0;
+
+	estop = estart + len;
+
+	/* 0-0 range represents "not set" */
+	if ((*start == 0) && (*stop == 0)) {
+		*start = estart;
+		*stop = estop;
+	} else if (*start <= *stop) {
+		/* increase the existing range */
+		if (estart < *start)
+			*start = estart;
+		if (estop > *stop)
+			*stop = estop;
+	} else {
+		/* "overflowing" interval, whereby *stop > *start */
+		if (estart <= *stop) {
+			if (estop > *stop)
+				*stop = estop;
+		} else if (estop > *start) {
+			if (estart < *start)
+				*start = estart;
+		}
+		/* minimize the range */
+		else if ((estop - *stop) < (*start - estart))
+			*stop = estop;
+		else
+			*start = estart;
+	}
+}
+
+#define MAX_INST_SIZE 6
+
+static void enable_all_hw_bp(struct kvm_vcpu *vcpu)
+{
+	unsigned long start, len;
+	u64 *cr9 = &vcpu->arch.sie_block->gcr[9];
+	u64 *cr10 = &vcpu->arch.sie_block->gcr[10];
+	u64 *cr11 = &vcpu->arch.sie_block->gcr[11];
+	int i;
+
+	if (vcpu->arch.guestdbg.nr_hw_bp <= 0 ||
+	    vcpu->arch.guestdbg.hw_bp_info == NULL)
+		return;
+
+	/*
+	 * If the guest is not interested in branching events, we can safely
+	 * limit them to the PER address range.
+	 */
+	if (!(*cr9 & PER_EVENT_BRANCH))
+		*cr9 |= PER_CONTROL_BRANCH_ADDRESS;
+	*cr9 |= PER_EVENT_IFETCH | PER_EVENT_BRANCH;
+
+	for (i = 0; i < vcpu->arch.guestdbg.nr_hw_bp; i++) {
+		start = vcpu->arch.guestdbg.hw_bp_info[i].addr;
+		len = vcpu->arch.guestdbg.hw_bp_info[i].len;
+
+		/*
+		 * The instruction in front of the desired bp has to
+		 * report instruction-fetching events
+		 */
+		if (start < MAX_INST_SIZE) {
+			len += start;
+			start = 0;
+		} else {
+			start -= MAX_INST_SIZE;
+			len += MAX_INST_SIZE;
+		}
+
+		extend_address_range(cr10, cr11, start, len);
+	}
+}
+
+static void enable_all_hw_wp(struct kvm_vcpu *vcpu)
+{
+	unsigned long start, len;
+	u64 *cr9 = &vcpu->arch.sie_block->gcr[9];
+	u64 *cr10 = &vcpu->arch.sie_block->gcr[10];
+	u64 *cr11 = &vcpu->arch.sie_block->gcr[11];
+	int i;
+
+	if (vcpu->arch.guestdbg.nr_hw_wp <= 0 ||
+	    vcpu->arch.guestdbg.hw_wp_info == NULL)
+		return;
+
+	/* if host uses storage alternation for special address
+	 * spaces, enable all events and give all to the guest */
+	if (*cr9 & PER_EVENT_STORE && *cr9 & PER_CONTROL_ALTERATION) {
+		*cr9 &= ~PER_CONTROL_ALTERATION;
+		*cr10 = 0;
+		*cr11 = -1UL;
+	} else {
+		*cr9 &= ~PER_CONTROL_ALTERATION;
+		*cr9 |= PER_EVENT_STORE;
+
+		for (i = 0; i < vcpu->arch.guestdbg.nr_hw_wp; i++) {
+			start = vcpu->arch.guestdbg.hw_wp_info[i].addr;
+			len = vcpu->arch.guestdbg.hw_wp_info[i].len;
+
+			extend_address_range(cr10, cr11, start, len);
+		}
+	}
+}
+
+void kvm_s390_backup_guest_per_regs(struct kvm_vcpu *vcpu)
+{
+	vcpu->arch.guestdbg.cr0 = vcpu->arch.sie_block->gcr[0];
+	vcpu->arch.guestdbg.cr9 = vcpu->arch.sie_block->gcr[9];
+	vcpu->arch.guestdbg.cr10 = vcpu->arch.sie_block->gcr[10];
+	vcpu->arch.guestdbg.cr11 = vcpu->arch.sie_block->gcr[11];
+}
+
+void kvm_s390_restore_guest_per_regs(struct kvm_vcpu *vcpu)
+{
+	vcpu->arch.sie_block->gcr[0] = vcpu->arch.guestdbg.cr0;
+	vcpu->arch.sie_block->gcr[9] = vcpu->arch.guestdbg.cr9;
+	vcpu->arch.sie_block->gcr[10] = vcpu->arch.guestdbg.cr10;
+	vcpu->arch.sie_block->gcr[11] = vcpu->arch.guestdbg.cr11;
+}
+
+void kvm_s390_patch_guest_per_regs(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * TODO: if guest psw has per enabled, otherwise 0s!
+	 * This reduces the amount of reported events.
+	 * Need to intercept all psw changes!
+	 */
+
+	if (guestdbg_sstep_enabled(vcpu)) {
+		/* disable timer (clock-comparator) interrupts */
+		vcpu->arch.sie_block->gcr[0] &= ~CR0_CLOCK_COMPARATOR_SUBMASK;
+		vcpu->arch.sie_block->gcr[9] |= PER_EVENT_IFETCH;
+		vcpu->arch.sie_block->gcr[10] = 0;
+		vcpu->arch.sie_block->gcr[11] = -1UL;
+	}
+
+	if (guestdbg_hw_bp_enabled(vcpu)) {
+		enable_all_hw_bp(vcpu);
+		enable_all_hw_wp(vcpu);
+	}
+
+	/* TODO: Instruction-fetching-nullification not allowed for now */
+	if (vcpu->arch.sie_block->gcr[9] & PER_EVENT_NULLIFICATION)
+		vcpu->arch.sie_block->gcr[9] &= ~PER_EVENT_NULLIFICATION;
+}
+
+#define MAX_WP_SIZE 100
+
+static int __import_wp_info(struct kvm_vcpu *vcpu,
+			    struct kvm_hw_breakpoint *bp_data,
+			    struct kvm_hw_wp_info_arch *wp_info)
+{
+	int ret = 0;
+	wp_info->len = bp_data->len;
+	wp_info->addr = bp_data->addr;
+	wp_info->phys_addr = bp_data->phys_addr;
+	wp_info->old_data = NULL;
+
+	if (wp_info->len < 0 || wp_info->len > MAX_WP_SIZE)
+		return -EINVAL;
+
+	wp_info->old_data = kmalloc(bp_data->len, GFP_KERNEL);
+	if (!wp_info->old_data)
+		return -ENOMEM;
+	/* try to backup the original value */
+	ret = read_guest_abs(vcpu, wp_info->phys_addr, wp_info->old_data,
+			     wp_info->len);
+	if (ret) {
+		kfree(wp_info->old_data);
+		wp_info->old_data = NULL;
+	}
+
+	return ret;
+}
+
+#define MAX_BP_COUNT 50
+
+int kvm_s390_import_bp_data(struct kvm_vcpu *vcpu,
+			    struct kvm_guest_debug *dbg)
+{
+	int ret = 0, nr_wp = 0, nr_bp = 0, i;
+	struct kvm_hw_breakpoint *bp_data = NULL;
+	struct kvm_hw_wp_info_arch *wp_info = NULL;
+	struct kvm_hw_bp_info_arch *bp_info = NULL;
+
+	if (dbg->arch.nr_hw_bp <= 0 || !dbg->arch.hw_bp)
+		return 0;
+	else if (dbg->arch.nr_hw_bp > MAX_BP_COUNT)
+		return -EINVAL;
+
+	bp_data = memdup_user(dbg->arch.hw_bp,
+			      sizeof(*bp_data) * dbg->arch.nr_hw_bp);
+	if (IS_ERR(bp_data))
+		return PTR_ERR(bp_data);
+
+	for (i = 0; i < dbg->arch.nr_hw_bp; i++) {
+		switch (bp_data[i].type) {
+		case KVM_HW_WP_WRITE:
+			nr_wp++;
+			break;
+		case KVM_HW_BP:
+			nr_bp++;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (nr_wp > 0) {
+		wp_info = kmalloc_array(nr_wp,
+					sizeof(*wp_info),
+					GFP_KERNEL);
+		if (!wp_info) {
+			ret = -ENOMEM;
+			goto error;
+		}
+	}
+	if (nr_bp > 0) {
+		bp_info = kmalloc_array(nr_bp,
+					sizeof(*bp_info),
+					GFP_KERNEL);
+		if (!bp_info) {
+			ret = -ENOMEM;
+			goto error;
+		}
+	}
+
+	for (nr_wp = 0, nr_bp = 0, i = 0; i < dbg->arch.nr_hw_bp; i++) {
+		switch (bp_data[i].type) {
+		case KVM_HW_WP_WRITE:
+			ret = __import_wp_info(vcpu, &bp_data[i],
+					       &wp_info[nr_wp]);
+			if (ret)
+				goto error;
+			nr_wp++;
+			break;
+		case KVM_HW_BP:
+			bp_info[nr_bp].len = bp_data[i].len;
+			bp_info[nr_bp].addr = bp_data[i].addr;
+			nr_bp++;
+			break;
+		}
+	}
+
+	vcpu->arch.guestdbg.nr_hw_bp = nr_bp;
+	vcpu->arch.guestdbg.hw_bp_info = bp_info;
+	vcpu->arch.guestdbg.nr_hw_wp = nr_wp;
+	vcpu->arch.guestdbg.hw_wp_info = wp_info;
+	return 0;
+error:
+	kfree(bp_data);
+	kfree(wp_info);
+	kfree(bp_info);
+	return ret;
+}
+
+void kvm_s390_clear_bp_data(struct kvm_vcpu *vcpu)
+{
+	int i;
+	struct kvm_hw_wp_info_arch *hw_wp_info = NULL;
+
+	for (i = 0; i < vcpu->arch.guestdbg.nr_hw_wp; i++) {
+		hw_wp_info = &vcpu->arch.guestdbg.hw_wp_info[i];
+		kfree(hw_wp_info->old_data);
+		hw_wp_info->old_data = NULL;
+	}
+	kfree(vcpu->arch.guestdbg.hw_wp_info);
+	vcpu->arch.guestdbg.hw_wp_info = NULL;
+
+	kfree(vcpu->arch.guestdbg.hw_bp_info);
+	vcpu->arch.guestdbg.hw_bp_info = NULL;
+
+	vcpu->arch.guestdbg.nr_hw_wp = 0;
+	vcpu->arch.guestdbg.nr_hw_bp = 0;
+}
+
+static inline int in_addr_range(u64 addr, u64 a, u64 b)
+{
+	if (a <= b)
+		return (addr >= a) && (addr <= b);
+	else
+		/* "overflowing" interval */
+		return (addr >= a) || (addr <= b);
+}
+
+#define end_of_range(bp_info) (bp_info->addr + bp_info->len - 1)
+
+static struct kvm_hw_bp_info_arch *find_hw_bp(struct kvm_vcpu *vcpu,
+					      unsigned long addr)
+{
+	struct kvm_hw_bp_info_arch *bp_info = vcpu->arch.guestdbg.hw_bp_info;
+	int i;
+
+	if (vcpu->arch.guestdbg.nr_hw_bp == 0)
+		return NULL;
+
+	for (i = 0; i < vcpu->arch.guestdbg.nr_hw_bp; i++) {
+		/* addr is directly the start or in the range of a bp */
+		if (addr == bp_info->addr)
+			goto found;
+		if (bp_info->len > 0 &&
+		    in_addr_range(addr, bp_info->addr, end_of_range(bp_info)))
+			goto found;
+
+		bp_info++;
+	}
+
+	return NULL;
+found:
+	return bp_info;
+}
+
+static struct kvm_hw_wp_info_arch *any_wp_changed(struct kvm_vcpu *vcpu)
+{
+	int i;
+	struct kvm_hw_wp_info_arch *wp_info = NULL;
+	void *temp = NULL;
+
+	if (vcpu->arch.guestdbg.nr_hw_wp == 0)
+		return NULL;
+
+	for (i = 0; i < vcpu->arch.guestdbg.nr_hw_wp; i++) {
+		wp_info = &vcpu->arch.guestdbg.hw_wp_info[i];
+		if (!wp_info || !wp_info->old_data || wp_info->len <= 0)
+			continue;
+
+		temp = kmalloc(wp_info->len, GFP_KERNEL);
+		if (!temp)
+			continue;
+
+		/* refetch the wp data and compare it to the old value */
+		if (!read_guest_abs(vcpu, wp_info->phys_addr, temp,
+				    wp_info->len)) {
+			if (memcmp(temp, wp_info->old_data, wp_info->len)) {
+				kfree(temp);
+				return wp_info;
+			}
+		}
+		kfree(temp);
+		temp = NULL;
+	}
+
+	return NULL;
+}
+
+void kvm_s390_prepare_debug_exit(struct kvm_vcpu *vcpu)
+{
+	vcpu->run->exit_reason = KVM_EXIT_DEBUG;
+	vcpu->guest_debug &= ~KVM_GUESTDBG_EXIT_PENDING;
+}
+
+#define PER_CODE_MASK		(PER_EVENT_MASK >> 24)
+#define PER_CODE_BRANCH		(PER_EVENT_BRANCH >> 24)
+#define PER_CODE_IFETCH		(PER_EVENT_IFETCH >> 24)
+#define PER_CODE_STORE		(PER_EVENT_STORE >> 24)
+#define PER_CODE_STORE_REAL	(PER_EVENT_STORE_REAL >> 24)
+
+#define per_bp_event(code) \
+			(code & (PER_CODE_IFETCH | PER_CODE_BRANCH))
+#define per_write_wp_event(code) \
+			(code & (PER_CODE_STORE | PER_CODE_STORE_REAL))
+
+static int debug_exit_required(struct kvm_vcpu *vcpu, u8 perc,
+			       unsigned long peraddr)
+{
+	struct kvm_debug_exit_arch *debug_exit = &vcpu->run->debug.arch;
+	struct kvm_hw_wp_info_arch *wp_info = NULL;
+	struct kvm_hw_bp_info_arch *bp_info = NULL;
+	unsigned long addr = vcpu->arch.sie_block->gpsw.addr;
+
+	if (guestdbg_hw_bp_enabled(vcpu)) {
+		if (per_write_wp_event(perc) &&
+		    vcpu->arch.guestdbg.nr_hw_wp > 0) {
+			wp_info = any_wp_changed(vcpu);
+			if (wp_info) {
+				debug_exit->addr = wp_info->addr;
+				debug_exit->type = KVM_HW_WP_WRITE;
+				goto exit_required;
+			}
+		}
+		if (per_bp_event(perc) &&
+			 vcpu->arch.guestdbg.nr_hw_bp > 0) {
+			bp_info = find_hw_bp(vcpu, addr);
+			/* remove duplicate events if PC==PER address */
+			if (bp_info && (addr != peraddr)) {
+				debug_exit->addr = addr;
+				debug_exit->type = KVM_HW_BP;
+				vcpu->arch.guestdbg.last_bp = addr;
+				goto exit_required;
+			}
+			/* breakpoint missed */
+			bp_info = find_hw_bp(vcpu, peraddr);
+			if (bp_info && vcpu->arch.guestdbg.last_bp != peraddr) {
+				debug_exit->addr = peraddr;
+				debug_exit->type = KVM_HW_BP;
+				goto exit_required;
+			}
+		}
+	}
+	if (guestdbg_sstep_enabled(vcpu) && per_bp_event(perc)) {
+		debug_exit->addr = addr;
+		debug_exit->type = KVM_SINGLESTEP;
+		goto exit_required;
+	}
+
+	return 0;
+exit_required:
+	return 1;
+}
+
+static int per_fetched_addr(struct kvm_vcpu *vcpu, unsigned long *addr)
+{
+	u8 exec_ilen = 0;
+	u16 opcode[3];
+	int rc;
+
+	if (vcpu->arch.sie_block->icptcode == ICPT_PROGI) {
+		/* PER address references the fetched or the execute instr */
+		*addr = vcpu->arch.sie_block->peraddr;
+		/*
+		 * Manually detect if we have an EXECUTE instruction. As
+		 * instructions are always 2 byte aligned we can read the
+		 * first two bytes unconditionally
+		 */
+		rc = read_guest_instr(vcpu, *addr, &opcode, 2);
+		if (rc)
+			return rc;
+		if (opcode[0] >> 8 == 0x44)
+			exec_ilen = 4;
+		if ((opcode[0] & 0xff0f) == 0xc600)
+			exec_ilen = 6;
+	} else {
+		/* instr was suppressed, calculate the responsible instr */
+		*addr = __rewind_psw(vcpu->arch.sie_block->gpsw,
+				     kvm_s390_get_ilen(vcpu));
+		if (vcpu->arch.sie_block->icptstatus & 0x01) {
+			exec_ilen = (vcpu->arch.sie_block->icptstatus & 0x60) >> 4;
+			if (!exec_ilen)
+				exec_ilen = 4;
+		}
+	}
+
+	if (exec_ilen) {
+		/* read the complete EXECUTE instr to detect the fetched addr */
+		rc = read_guest_instr(vcpu, *addr, &opcode, exec_ilen);
+		if (rc)
+			return rc;
+		if (exec_ilen == 6) {
+			/* EXECUTE RELATIVE LONG - RIL-b format */
+			s32 rl = *((s32 *) (opcode + 1));
+
+			/* rl is a _signed_ 32 bit value specifying halfwords */
+			*addr += (u64)(s64) rl * 2;
+		} else {
+			/* EXECUTE - RX-a format */
+			u32 base = (opcode[1] & 0xf000) >> 12;
+			u32 disp = opcode[1] & 0x0fff;
+			u32 index = opcode[0] & 0x000f;
+
+			*addr = base ? vcpu->run->s.regs.gprs[base] : 0;
+			*addr += index ? vcpu->run->s.regs.gprs[index] : 0;
+			*addr += disp;
+		}
+		*addr = kvm_s390_logical_to_effective(vcpu, *addr);
+	}
+	return 0;
+}
+
+#define guest_per_enabled(vcpu) \
+			     (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER)
+
+int kvm_s390_handle_per_ifetch_icpt(struct kvm_vcpu *vcpu)
+{
+	const u64 cr10 = vcpu->arch.sie_block->gcr[10];
+	const u64 cr11 = vcpu->arch.sie_block->gcr[11];
+	const u8 ilen = kvm_s390_get_ilen(vcpu);
+	struct kvm_s390_pgm_info pgm_info = {
+		.code = PGM_PER,
+		.per_code = PER_CODE_IFETCH,
+		.per_address = __rewind_psw(vcpu->arch.sie_block->gpsw, ilen),
+	};
+	unsigned long fetched_addr;
+	int rc;
+
+	/*
+	 * The PSW points to the next instruction, therefore the intercepted
+	 * instruction generated a PER i-fetch event. PER address therefore
+	 * points at the previous PSW address (could be an EXECUTE function).
+	 */
+	if (!guestdbg_enabled(vcpu))
+		return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
+
+	if (debug_exit_required(vcpu, pgm_info.per_code, pgm_info.per_address))
+		vcpu->guest_debug |= KVM_GUESTDBG_EXIT_PENDING;
+
+	if (!guest_per_enabled(vcpu) ||
+	    !(vcpu->arch.sie_block->gcr[9] & PER_EVENT_IFETCH))
+		return 0;
+
+	rc = per_fetched_addr(vcpu, &fetched_addr);
+	if (rc < 0)
+		return rc;
+	if (rc)
+		/* instruction-fetching exceptions */
+		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+
+	if (in_addr_range(fetched_addr, cr10, cr11))
+		return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
+	return 0;
+}
+
+static int filter_guest_per_event(struct kvm_vcpu *vcpu)
+{
+	const u8 perc = vcpu->arch.sie_block->perc;
+	u64 addr = vcpu->arch.sie_block->gpsw.addr;
+	u64 cr9 = vcpu->arch.sie_block->gcr[9];
+	u64 cr10 = vcpu->arch.sie_block->gcr[10];
+	u64 cr11 = vcpu->arch.sie_block->gcr[11];
+	/* filter all events, demanded by the guest */
+	u8 guest_perc = perc & (cr9 >> 24) & PER_CODE_MASK;
+	unsigned long fetched_addr;
+	int rc;
+
+	if (!guest_per_enabled(vcpu))
+		guest_perc = 0;
+
+	/* filter "successful-branching" events */
+	if (guest_perc & PER_CODE_BRANCH &&
+	    cr9 & PER_CONTROL_BRANCH_ADDRESS &&
+	    !in_addr_range(addr, cr10, cr11))
+		guest_perc &= ~PER_CODE_BRANCH;
+
+	/* filter "instruction-fetching" events */
+	if (guest_perc & PER_CODE_IFETCH) {
+		rc = per_fetched_addr(vcpu, &fetched_addr);
+		if (rc < 0)
+			return rc;
+		/*
+		 * Don't inject an irq on exceptions. This would make handling
+		 * on icpt code 8 very complex (as PSW was already rewound).
+		 */
+		if (rc || !in_addr_range(fetched_addr, cr10, cr11))
+			guest_perc &= ~PER_CODE_IFETCH;
+	}
+
+	/* All other PER events will be given to the guest */
+	/* TODO: Check altered address/address space */
+
+	vcpu->arch.sie_block->perc = guest_perc;
+
+	if (!guest_perc)
+		vcpu->arch.sie_block->iprcc &= ~PGM_PER;
+	return 0;
+}
+
+#define pssec(vcpu) (vcpu->arch.sie_block->gcr[1] & _ASCE_SPACE_SWITCH)
+#define hssec(vcpu) (vcpu->arch.sie_block->gcr[13] & _ASCE_SPACE_SWITCH)
+#define old_ssec(vcpu) ((vcpu->arch.sie_block->tecmc >> 31) & 0x1)
+#define old_as_is_home(vcpu) !(vcpu->arch.sie_block->tecmc & 0xffff)
+
+int kvm_s390_handle_per_event(struct kvm_vcpu *vcpu)
+{
+	int rc, new_as;
+
+	if (debug_exit_required(vcpu, vcpu->arch.sie_block->perc,
+				vcpu->arch.sie_block->peraddr))
+		vcpu->guest_debug |= KVM_GUESTDBG_EXIT_PENDING;
+
+	rc = filter_guest_per_event(vcpu);
+	if (rc)
+		return rc;
+
+	/*
+	 * Only RP, SAC, SACF, PT, PTI, PR, PC instructions can trigger
+	 * a space-switch event. PER events enforce space-switch events
+	 * for these instructions. So if no PER event for the guest is left,
+	 * we might have to filter the space-switch element out, too.
+	 */
+	if (vcpu->arch.sie_block->iprcc == PGM_SPACE_SWITCH) {
+		vcpu->arch.sie_block->iprcc = 0;
+		new_as = psw_bits(vcpu->arch.sie_block->gpsw).as;
+
+		/*
+		 * If the AS changed from / to home, we had RP, SAC or SACF
+		 * instruction. Check primary and home space-switch-event
+		 * controls. (theoretically home -> home produced no event)
+		 */
+		if (((new_as == PSW_BITS_AS_HOME) ^ old_as_is_home(vcpu)) &&
+		    (pssec(vcpu) || hssec(vcpu)))
+			vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH;
+
+		/*
+		 * PT, PTI, PR, PC instruction operate on primary AS only. Check
+		 * if the primary-space-switch-event control was or got set.
+		 */
+		if (new_as == PSW_BITS_AS_PRIMARY && !old_as_is_home(vcpu) &&
+		    (pssec(vcpu) || old_ssec(vcpu)))
+			vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH;
+	}
+	return 0;
+}