arch/powerpc/kvm/book3s_hv_rmhandlers.S - linux - Git at Google

 /*
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License, version 2, as
  * published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
  *
  * Derived from book3s_rmhandlers.S and other files, which are:
  *
  * Copyright SUSE Linux Products GmbH 2009
  *
  * Authors: Alexander Graf <agraf@suse.de>
  */

 #include <asm/ppc_asm.h>
 #include <asm/kvm_asm.h>
 #include <asm/reg.h>
 #include <asm/mmu.h>
 #include <asm/page.h>
 #include <asm/ptrace.h>
 #include <asm/hvcall.h>
 #include <asm/asm-offsets.h>
 #include <asm/exception-64s.h>
 #include <asm/kvm_book3s_asm.h>
 #include <asm/book3s/64/mmu-hash.h>
 #include <asm/tm.h>
 #include <asm/opal.h>
 #include <asm/xive-regs.h>
 #include <asm/thread_info.h>
 #include <asm/asm-compat.h>
 #include <asm/feature-fixups.h>

 /* Sign-extend HDEC if not on POWER9 */
 #define EXTEND_HDEC(reg)			\
 BEGIN_FTR_SECTION;				\
 	extsw	reg, reg;			\
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)

 /* Values in HSTATE_NAPPING(r13) */
 #define NAPPING_CEDE	1
 #define NAPPING_NOVCPU	2

 /* Stack frame offsets for kvmppc_hv_entry */
 #define SFS			160
 #define STACK_SLOT_TRAP		(SFS-4)
 #define STACK_SLOT_TID		(SFS-16)
 #define STACK_SLOT_PSSCR	(SFS-24)
 #define STACK_SLOT_PID		(SFS-32)
 #define STACK_SLOT_IAMR		(SFS-40)
 #define STACK_SLOT_CIABR	(SFS-48)
 #define STACK_SLOT_DAWR		(SFS-56)
 #define STACK_SLOT_DAWRX	(SFS-64)
 #define STACK_SLOT_HFSCR	(SFS-72)

 /*
  * Call kvmppc_hv_entry in real mode.
  * Must be called with interrupts hard-disabled.
  *
  * Input Registers:
  *
  * LR = return address to continue at after eventually re-enabling MMU
  */
 _GLOBAL_TOC(kvmppc_hv_entry_trampoline)
 	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
 	stdu	r1, -112(r1)
 	mfmsr	r10
 	std	r10, HSTATE_HOST_MSR(r13)
 	LOAD_REG_ADDR(r5, kvmppc_call_hv_entry)
 	li	r0,MSR_RI
 	andc	r0,r10,r0
 	li	r6,MSR_IR | MSR_DR
 	andc	r6,r10,r6
 	mtmsrd	r0,1		/* clear RI in MSR */
 	mtsrr0	r5
 	mtsrr1	r6
 	RFI_TO_KERNEL

 kvmppc_call_hv_entry:
 BEGIN_FTR_SECTION
 	/* On P9, do LPCR setting, if necessary */
 	ld	r3, HSTATE_SPLIT_MODE(r13)
 	cmpdi	r3, 0
 	beq	46f
 	lwz	r4, KVM_SPLIT_DO_SET(r3)
 	cmpwi	r4, 0
 	beq	46f
 	bl	kvmhv_p9_set_lpcr
 	nop
 46:
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)

 	ld	r4, HSTATE_KVM_VCPU(r13)
 	bl	kvmppc_hv_entry

 	/* Back from guest - restore host state and return to caller */

 BEGIN_FTR_SECTION
 	/* Restore host DABR and DABRX */
 	ld	r5,HSTATE_DABR(r13)
 	li	r6,7
 	mtspr	SPRN_DABR,r5
 	mtspr	SPRN_DABRX,r6
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)

 	/* Restore SPRG3 */
 	ld	r3,PACA_SPRG_VDSO(r13)
 	mtspr	SPRN_SPRG_VDSO_WRITE,r3

 	/* Reload the host's PMU registers */
 	lbz	r4, PACA_PMCINUSE(r13) /* is the host using the PMU? */
 	cmpwi	r4, 0
 	beq	23f			/* skip if not */
 BEGIN_FTR_SECTION
 	ld	r3, HSTATE_MMCR0(r13)
 	andi.	r4, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO
 	cmpwi	r4, MMCR0_PMAO
 	beql	kvmppc_fix_pmao
 END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)
 	lwz	r3, HSTATE_PMC1(r13)
 	lwz	r4, HSTATE_PMC2(r13)
 	lwz	r5, HSTATE_PMC3(r13)
 	lwz	r6, HSTATE_PMC4(r13)
 	lwz	r8, HSTATE_PMC5(r13)
 	lwz	r9, HSTATE_PMC6(r13)
 	mtspr	SPRN_PMC1, r3
 	mtspr	SPRN_PMC2, r4
 	mtspr	SPRN_PMC3, r5
 	mtspr	SPRN_PMC4, r6
 	mtspr	SPRN_PMC5, r8
 	mtspr	SPRN_PMC6, r9
 	ld	r3, HSTATE_MMCR0(r13)
 	ld	r4, HSTATE_MMCR1(r13)
 	ld	r5, HSTATE_MMCRA(r13)
 	ld	r6, HSTATE_SIAR(r13)
 	ld	r7, HSTATE_SDAR(r13)
 	mtspr	SPRN_MMCR1, r4
 	mtspr	SPRN_MMCRA, r5
 	mtspr	SPRN_SIAR, r6
 	mtspr	SPRN_SDAR, r7
 BEGIN_FTR_SECTION
 	ld	r8, HSTATE_MMCR2(r13)
 	ld	r9, HSTATE_SIER(r13)
 	mtspr	SPRN_MMCR2, r8
 	mtspr	SPRN_SIER, r9
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	mtspr	SPRN_MMCR0, r3
 	isync
 23:

 	/*
 	 * Reload DEC.  HDEC interrupts were disabled when
 	 * we reloaded the host's LPCR value.
 	 */
 	ld	r3, HSTATE_DECEXP(r13)
 	mftb	r4
 	subf	r4, r4, r3
 	mtspr	SPRN_DEC, r4

 	/* hwthread_req may have got set by cede or no vcpu, so clear it */
 	li	r0, 0
 	stb	r0, HSTATE_HWTHREAD_REQ(r13)

 	/*
 	 * For external interrupts we need to call the Linux
 	 * handler to process the interrupt. We do that by jumping
 	 * to absolute address 0x500 for external interrupts.
 	 * The [h]rfid at the end of the handler will return to
 	 * the book3s_hv_interrupts.S code. For other interrupts
 	 * we do the rfid to get back to the book3s_hv_interrupts.S
 	 * code here.
 	 */
 	ld	r8, 112+PPC_LR_STKOFF(r1)
 	addi	r1, r1, 112
 	ld	r7, HSTATE_HOST_MSR(r13)

 	/* Return the trap number on this thread as the return value */
 	mr	r3, r12

 	/*
 	 * If we came back from the guest via a relocation-on interrupt,
 	 * we will be in virtual mode at this point, which makes it a
 	 * little easier to get back to the caller.
 	 */
 	mfmsr	r0
 	andi.	r0, r0, MSR_IR		/* in real mode? */
 	bne	.Lvirt_return

 	/* RFI into the highmem handler */
 	mfmsr	r6
 	li	r0, MSR_RI
 	andc	r6, r6, r0
 	mtmsrd	r6, 1			/* Clear RI in MSR */
 	mtsrr0	r8
 	mtsrr1	r7
 	RFI_TO_KERNEL

 	/* Virtual-mode return */
 .Lvirt_return:
 	mtlr	r8
 	blr

 kvmppc_primary_no_guest:
 	/* We handle this much like a ceded vcpu */
 	/* put the HDEC into the DEC, since HDEC interrupts don't wake us */
 	/* HDEC may be larger than DEC for arch >= v3.00, but since the */
 	/* HDEC value came from DEC in the first place, it will fit */
 	mfspr	r3, SPRN_HDEC
 	mtspr	SPRN_DEC, r3
 	/*
 	 * Make sure the primary has finished the MMU switch.
 	 * We should never get here on a secondary thread, but
 	 * check it for robustness' sake.
 	 */
 	ld	r5, HSTATE_KVM_VCORE(r13)
 65:	lbz	r0, VCORE_IN_GUEST(r5)
 	cmpwi	r0, 0
 	beq	65b
 	/* Set LPCR. */
 	ld	r8,VCORE_LPCR(r5)
 	mtspr	SPRN_LPCR,r8
 	isync
 	/* set our bit in napping_threads */
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	lbz	r7, HSTATE_PTID(r13)
 	li	r0, 1
 	sld	r0, r0, r7
 	addi	r6, r5, VCORE_NAPPING_THREADS
 1:	lwarx	r3, 0, r6
 	or	r3, r3, r0
 	stwcx.	r3, 0, r6
 	bne	1b
 	/* order napping_threads update vs testing entry_exit_map */
 	isync
 	li	r12, 0
 	lwz	r7, VCORE_ENTRY_EXIT(r5)
 	cmpwi	r7, 0x100
 	bge	kvm_novcpu_exit	/* another thread already exiting */
 	li	r3, NAPPING_NOVCPU
 	stb	r3, HSTATE_NAPPING(r13)

 	li	r3, 0		/* Don't wake on privileged (OS) doorbell */
 	b	kvm_do_nap

 /*
  * kvm_novcpu_wakeup
  *	Entered from kvm_start_guest if kvm_hstate.napping is set
  *	to NAPPING_NOVCPU
  *		r2 = kernel TOC
  *		r13 = paca
  */
 kvm_novcpu_wakeup:
 	ld	r1, HSTATE_HOST_R1(r13)
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	li	r0, 0
 	stb	r0, HSTATE_NAPPING(r13)

 	/* check the wake reason */
 	bl	kvmppc_check_wake_reason

 	/*
 	 * Restore volatile registers since we could have called
 	 * a C routine in kvmppc_check_wake_reason.
 	 *	r5 = VCORE
 	 */
 	ld	r5, HSTATE_KVM_VCORE(r13)

 	/* see if any other thread is already exiting */
 	lwz	r0, VCORE_ENTRY_EXIT(r5)
 	cmpwi	r0, 0x100
 	bge	kvm_novcpu_exit

 	/* clear our bit in napping_threads */
 	lbz	r7, HSTATE_PTID(r13)
 	li	r0, 1
 	sld	r0, r0, r7
 	addi	r6, r5, VCORE_NAPPING_THREADS
 4:	lwarx	r7, 0, r6
 	andc	r7, r7, r0
 	stwcx.	r7, 0, r6
 	bne	4b

 	/* See if the wake reason means we need to exit */
 	cmpdi	r3, 0
 	bge	kvm_novcpu_exit

 	/* See if our timeslice has expired (HDEC is negative) */
 	mfspr	r0, SPRN_HDEC
 	EXTEND_HDEC(r0)
 	li	r12, BOOK3S_INTERRUPT_HV_DECREMENTER
 	cmpdi	r0, 0
 	blt	kvm_novcpu_exit

 	/* Got an IPI but other vcpus aren't yet exiting, must be a latecomer */
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	cmpdi	r4, 0
 	beq	kvmppc_primary_no_guest

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r4, VCPU_TB_RMENTRY
 	bl	kvmhv_start_timing
 #endif
 	b	kvmppc_got_guest

 kvm_novcpu_exit:
 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	cmpdi	r4, 0
 	beq	13f
 	addi	r3, r4, VCPU_TB_RMEXIT
 	bl	kvmhv_accumulate_time
 #endif
 13:	mr	r3, r12
 	stw	r12, STACK_SLOT_TRAP(r1)
 	bl	kvmhv_commence_exit
 	nop
 	b	kvmhv_switch_to_host

 /*
  * We come in here when wakened from nap mode.
  * Relocation is off and most register values are lost.
  * r13 points to the PACA.
  * r3 contains the SRR1 wakeup value, SRR1 is trashed.
  */
 	.globl	kvm_start_guest
 kvm_start_guest:
 	/* Set runlatch bit the minute you wake up from nap */
 	mfspr	r0, SPRN_CTRLF
 	ori 	r0, r0, 1
 	mtspr	SPRN_CTRLT, r0

 	/*
 	 * Could avoid this and pass it through in r3. For now,
 	 * code expects it to be in SRR1.
 	 */
 	mtspr	SPRN_SRR1,r3

 	ld	r2,PACATOC(r13)

 	li	r0,0
 	stb	r0,PACA_FTRACE_ENABLED(r13)

 	li	r0,KVM_HWTHREAD_IN_KVM
 	stb	r0,HSTATE_HWTHREAD_STATE(r13)

 	/* NV GPR values from power7_idle() will no longer be valid */
 	li	r0,1
 	stb	r0,PACA_NAPSTATELOST(r13)

 	/* were we napping due to cede? */
 	lbz	r0,HSTATE_NAPPING(r13)
 	cmpwi	r0,NAPPING_CEDE
 	beq	kvm_end_cede
 	cmpwi	r0,NAPPING_NOVCPU
 	beq	kvm_novcpu_wakeup

 	ld	r1,PACAEMERGSP(r13)
 	subi	r1,r1,STACK_FRAME_OVERHEAD

 	/*
 	 * We weren't napping due to cede, so this must be a secondary
 	 * thread being woken up to run a guest, or being woken up due
 	 * to a stray IPI.  (Or due to some machine check or hypervisor
 	 * maintenance interrupt while the core is in KVM.)
 	 */

 	/* Check the wake reason in SRR1 to see why we got here */
 	bl	kvmppc_check_wake_reason
 	/*
 	 * kvmppc_check_wake_reason could invoke a C routine, but we
 	 * have no volatile registers to restore when we return.
 	 */

 	cmpdi	r3, 0
 	bge	kvm_no_guest

 	/* get vcore pointer, NULL if we have nothing to run */
 	ld	r5,HSTATE_KVM_VCORE(r13)
 	cmpdi	r5,0
 	/* if we have no vcore to run, go back to sleep */
 	beq	kvm_no_guest

 kvm_secondary_got_guest:

 	/* Set HSTATE_DSCR(r13) to something sensible */
 	ld	r6, PACA_DSCR_DEFAULT(r13)
 	std	r6, HSTATE_DSCR(r13)

 	/* On thread 0 of a subcore, set HDEC to max */
 	lbz	r4, HSTATE_PTID(r13)
 	cmpwi	r4, 0
 	bne	63f
 	LOAD_REG_ADDR(r6, decrementer_max)
 	ld	r6, 0(r6)
 	mtspr	SPRN_HDEC, r6
 	/* and set per-LPAR registers, if doing dynamic micro-threading */
 	ld	r6, HSTATE_SPLIT_MODE(r13)
 	cmpdi	r6, 0
 	beq	63f
 BEGIN_FTR_SECTION
 	ld	r0, KVM_SPLIT_RPR(r6)
 	mtspr	SPRN_RPR, r0
 	ld	r0, KVM_SPLIT_PMMAR(r6)
 	mtspr	SPRN_PMMAR, r0
 	ld	r0, KVM_SPLIT_LDBAR(r6)
 	mtspr	SPRN_LDBAR, r0
 	isync
 FTR_SECTION_ELSE
 	/* On P9 we use the split_info for coordinating LPCR changes */
 	lwz	r4, KVM_SPLIT_DO_SET(r6)
 	cmpwi	r4, 0
 	beq	1f
 	mr	r3, r6
 	bl	kvmhv_p9_set_lpcr
 	nop
 1:
 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 63:
 	/* Order load of vcpu after load of vcore */
 	lwsync
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	bl	kvmppc_hv_entry

 	/* Back from the guest, go back to nap */
 	/* Clear our vcpu and vcore pointers so we don't come back in early */
 	li	r0, 0
 	std	r0, HSTATE_KVM_VCPU(r13)
 	/*
 	 * Once we clear HSTATE_KVM_VCORE(r13), the code in
 	 * kvmppc_run_core() is going to assume that all our vcpu
 	 * state is visible in memory.  This lwsync makes sure
 	 * that that is true.
 	 */
 	lwsync
 	std	r0, HSTATE_KVM_VCORE(r13)

 	/*
 	 * All secondaries exiting guest will fall through this path.
 	 * Before proceeding, just check for HMI interrupt and
 	 * invoke opal hmi handler. By now we are sure that the
 	 * primary thread on this core/subcore has already made partition
 	 * switch/TB resync and we are good to call opal hmi handler.
 	 */
 	cmpwi	r12, BOOK3S_INTERRUPT_HMI
 	bne	kvm_no_guest

 	li	r3,0			/* NULL argument */
 	bl	hmi_exception_realmode
 /*
  * At this point we have finished executing in the guest.
  * We need to wait for hwthread_req to become zero, since
  * we may not turn on the MMU while hwthread_req is non-zero.
  * While waiting we also need to check if we get given a vcpu to run.
  */
 kvm_no_guest:
 	lbz	r3, HSTATE_HWTHREAD_REQ(r13)
 	cmpwi	r3, 0
 	bne	53f
 	HMT_MEDIUM
 	li	r0, KVM_HWTHREAD_IN_KERNEL
 	stb	r0, HSTATE_HWTHREAD_STATE(r13)
 	/* need to recheck hwthread_req after a barrier, to avoid race */
 	sync
 	lbz	r3, HSTATE_HWTHREAD_REQ(r13)
 	cmpwi	r3, 0
 	bne	54f
 /*
  * We jump to pnv_wakeup_loss, which will return to the caller
  * of power7_nap in the powernv cpu offline loop.  The value we
  * put in r3 becomes the return value for power7_nap. pnv_wakeup_loss
  * requires SRR1 in r12.
  */
 	li	r3, LPCR_PECE0
 	mfspr	r4, SPRN_LPCR
 	rlwimi	r4, r3, 0, LPCR_PECE0 | LPCR_PECE1
 	mtspr	SPRN_LPCR, r4
 	li	r3, 0
 	mfspr	r12,SPRN_SRR1
 	b	pnv_wakeup_loss

 53:	HMT_LOW
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	cmpdi	r5, 0
 	bne	60f
 	ld	r3, HSTATE_SPLIT_MODE(r13)
 	cmpdi	r3, 0
 	beq	kvm_no_guest
 	lwz	r0, KVM_SPLIT_DO_SET(r3)
 	cmpwi	r0, 0
 	bne	kvmhv_do_set
 	lwz	r0, KVM_SPLIT_DO_RESTORE(r3)
 	cmpwi	r0, 0
 	bne	kvmhv_do_restore
 	lbz	r0, KVM_SPLIT_DO_NAP(r3)
 	cmpwi	r0, 0
 	beq	kvm_no_guest
 	HMT_MEDIUM
 	b	kvm_unsplit_nap
 60:	HMT_MEDIUM
 	b	kvm_secondary_got_guest

 54:	li	r0, KVM_HWTHREAD_IN_KVM
 	stb	r0, HSTATE_HWTHREAD_STATE(r13)
 	b	kvm_no_guest

 kvmhv_do_set:
 	/* Set LPCR, LPIDR etc. on P9 */
 	HMT_MEDIUM
 	bl	kvmhv_p9_set_lpcr
 	nop
 	b	kvm_no_guest

 kvmhv_do_restore:
 	HMT_MEDIUM
 	bl	kvmhv_p9_restore_lpcr
 	nop
 	b	kvm_no_guest

 /*
  * Here the primary thread is trying to return the core to
  * whole-core mode, so we need to nap.
  */
 kvm_unsplit_nap:
 	/*
 	 * When secondaries are napping in kvm_unsplit_nap() with
 	 * hwthread_req = 1, HMI goes ignored even though subcores are
 	 * already exited the guest. Hence HMI keeps waking up secondaries
 	 * from nap in a loop and secondaries always go back to nap since
 	 * no vcore is assigned to them. This makes impossible for primary
 	 * thread to get hold of secondary threads resulting into a soft
 	 * lockup in KVM path.
 	 *
 	 * Let us check if HMI is pending and handle it before we go to nap.
 	 */
 	cmpwi	r12, BOOK3S_INTERRUPT_HMI
 	bne	55f
 	li	r3, 0			/* NULL argument */
 	bl	hmi_exception_realmode
 55:
 	/*
 	 * Ensure that secondary doesn't nap when it has
 	 * its vcore pointer set.
 	 */
 	sync		/* matches smp_mb() before setting split_info.do_nap */
 	ld	r0, HSTATE_KVM_VCORE(r13)
 	cmpdi	r0, 0
 	bne	kvm_no_guest
 	/* clear any pending message */
 BEGIN_FTR_SECTION
 	lis	r6, (PPC_DBELL_SERVER << (63-36))@h
 	PPC_MSGCLR(6)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	/* Set kvm_split_mode.napped[tid] = 1 */
 	ld	r3, HSTATE_SPLIT_MODE(r13)
 	li	r0, 1
 	lbz	r4, HSTATE_TID(r13)
 	addi	r4, r4, KVM_SPLIT_NAPPED
 	stbx	r0, r3, r4
 	/* Check the do_nap flag again after setting napped[] */
 	sync
 	lbz	r0, KVM_SPLIT_DO_NAP(r3)
 	cmpwi	r0, 0
 	beq	57f
 	li	r3, (LPCR_PECEDH | LPCR_PECE0) >> 4
 	mfspr	r5, SPRN_LPCR
 	rlwimi	r5, r3, 4, (LPCR_PECEDP | LPCR_PECEDH | LPCR_PECE0 | LPCR_PECE1)
 	b	kvm_nap_sequence

 57:	li	r0, 0
 	stbx	r0, r3, r4
 	b	kvm_no_guest

 /******************************************************************************
  *                                                                            *
  *                               Entry code                                   *
  *                                                                            *
  *****************************************************************************/

 .global kvmppc_hv_entry
 kvmppc_hv_entry:

 	/* Required state:
 	 *
 	 * R4 = vcpu pointer (or NULL)
 	 * MSR = ~IR|DR
 	 * R13 = PACA
 	 * R1 = host R1
 	 * R2 = TOC
 	 * all other volatile GPRS = free
 	 * Does not preserve non-volatile GPRs or CR fields
 	 */
 	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
 	stdu	r1, -SFS(r1)

 	/* Save R1 in the PACA */
 	std	r1, HSTATE_HOST_R1(r13)

 	li	r6, KVM_GUEST_MODE_HOST_HV
 	stb	r6, HSTATE_IN_GUEST(r13)

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	/* Store initial timestamp */
 	cmpdi	r4, 0
 	beq	1f
 	addi	r3, r4, VCPU_TB_RMENTRY
 	bl	kvmhv_start_timing
 1:
 #endif

 	/* Use cr7 as an indication of radix mode */
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r9, VCORE_KVM(r5)	/* pointer to struct kvm */
 	lbz	r0, KVM_RADIX(r9)
 	cmpwi	cr7, r0, 0

 	/*
 	 * POWER7/POWER8 host -> guest partition switch code.
 	 * We don't have to lock against concurrent tlbies,
 	 * but we do have to coordinate across hardware threads.
 	 */
 	/* Set bit in entry map iff exit map is zero. */
 	li	r7, 1
 	lbz	r6, HSTATE_PTID(r13)
 	sld	r7, r7, r6
 	addi	r8, r5, VCORE_ENTRY_EXIT
 21:	lwarx	r3, 0, r8
 	cmpwi	r3, 0x100		/* any threads starting to exit? */
 	bge	secondary_too_late	/* if so we're too late to the party */
 	or	r3, r3, r7
 	stwcx.	r3, 0, r8
 	bne	21b

 	/* Primary thread switches to guest partition. */
 	cmpwi	r6,0
 	bne	10f

 	/* Radix has already switched LPID and flushed core TLB */
 	bne	cr7, 22f

 	lwz	r7,KVM_LPID(r9)
 BEGIN_FTR_SECTION
 	ld	r6,KVM_SDR1(r9)
 	li	r0,LPID_RSVD		/* switch to reserved LPID */
 	mtspr	SPRN_LPID,r0
 	ptesync
 	mtspr	SPRN_SDR1,r6		/* switch to partition page table */
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	mtspr	SPRN_LPID,r7
 	isync

 	/* See if we need to flush the TLB. Hash has to be done in RM */
 	lhz	r6,PACAPACAINDEX(r13)	/* test_bit(cpu, need_tlb_flush) */
 BEGIN_FTR_SECTION
 	/*
 	 * On POWER9, individual threads can come in here, but the
 	 * TLB is shared between the 4 threads in a core, hence
 	 * invalidating on one thread invalidates for all.
 	 * Thus we make all 4 threads use the same bit here.
 	 */
 	clrrdi	r6,r6,2
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	clrldi	r7,r6,64-6		/* extract bit number (6 bits) */
 	srdi	r6,r6,6			/* doubleword number */
 	sldi	r6,r6,3			/* address offset */
 	add	r6,r6,r9
 	addi	r6,r6,KVM_NEED_FLUSH	/* dword in kvm->arch.need_tlb_flush */
 	li	r8,1
 	sld	r8,r8,r7
 	ld	r7,0(r6)
 	and.	r7,r7,r8
 	beq	22f
 	/* Flush the TLB of any entries for this LPID */
 	lwz	r0,KVM_TLB_SETS(r9)
 	mtctr	r0
 	li	r7,0x800		/* IS field = 0b10 */
 	ptesync
 	li	r0,0			/* RS for P9 version of tlbiel */
 28:	tlbiel	r7			/* On P9, rs=0, RIC=0, PRS=0, R=0 */
 	addi	r7,r7,0x1000
 	bdnz	28b
 	ptesync
 23:	ldarx	r7,0,r6			/* clear the bit after TLB flushed */
 	andc	r7,r7,r8
 	stdcx.	r7,0,r6
 	bne	23b

 	/* Add timebase offset onto timebase */
 22:	ld	r8,VCORE_TB_OFFSET(r5)
 	cmpdi	r8,0
 	beq	37f
 	std	r8, VCORE_TB_OFFSET_APPL(r5)
 	mftb	r6		/* current host timebase */
 	add	r8,r8,r6
 	mtspr	SPRN_TBU40,r8	/* update upper 40 bits */
 	mftb	r7		/* check if lower 24 bits overflowed */
 	clrldi	r6,r6,40
 	clrldi	r7,r7,40
 	cmpld	r7,r6
 	bge	37f
 	addis	r8,r8,0x100	/* if so, increment upper 40 bits */
 	mtspr	SPRN_TBU40,r8

 	/* Load guest PCR value to select appropriate compat mode */
 37:	ld	r7, VCORE_PCR(r5)
 	cmpdi	r7, 0
 	beq	38f
 	mtspr	SPRN_PCR, r7
 38:

 BEGIN_FTR_SECTION
 	/* DPDES and VTB are shared between threads */
 	ld	r8, VCORE_DPDES(r5)
 	ld	r7, VCORE_VTB(r5)
 	mtspr	SPRN_DPDES, r8
 	mtspr	SPRN_VTB, r7
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)

 	/* Mark the subcore state as inside guest */
 	bl	kvmppc_subcore_enter_guest
 	nop
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	li	r0,1
 	stb	r0,VCORE_IN_GUEST(r5)	/* signal secondaries to continue */

 	/* Do we have a guest vcpu to run? */
 10:	cmpdi	r4, 0
 	beq	kvmppc_primary_no_guest
 kvmppc_got_guest:
 	/* Increment yield count if they have a VPA */
 	ld	r3, VCPU_VPA(r4)
 	cmpdi	r3, 0
 	beq	25f
 	li	r6, LPPACA_YIELDCOUNT
 	LWZX_BE	r5, r3, r6
 	addi	r5, r5, 1
 	STWX_BE	r5, r3, r6
 	li	r6, 1
 	stb	r6, VCPU_VPA_DIRTY(r4)
 25:

 	/* Save purr/spurr */
 	mfspr	r5,SPRN_PURR
 	mfspr	r6,SPRN_SPURR
 	std	r5,HSTATE_PURR(r13)
 	std	r6,HSTATE_SPURR(r13)
 	ld	r7,VCPU_PURR(r4)
 	ld	r8,VCPU_SPURR(r4)
 	mtspr	SPRN_PURR,r7
 	mtspr	SPRN_SPURR,r8

 	/* Save host values of some registers */
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_TIDR
 	mfspr	r6, SPRN_PSSCR
 	mfspr	r7, SPRN_PID
 	mfspr	r8, SPRN_IAMR
 	std	r5, STACK_SLOT_TID(r1)
 	std	r6, STACK_SLOT_PSSCR(r1)
 	std	r7, STACK_SLOT_PID(r1)
 	std	r8, STACK_SLOT_IAMR(r1)
 	mfspr	r5, SPRN_HFSCR
 	std	r5, STACK_SLOT_HFSCR(r1)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_CIABR
 	mfspr	r6, SPRN_DAWR
 	mfspr	r7, SPRN_DAWRX
 	std	r5, STACK_SLOT_CIABR(r1)
 	std	r6, STACK_SLOT_DAWR(r1)
 	std	r7, STACK_SLOT_DAWRX(r1)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)

 BEGIN_FTR_SECTION
 	/* Set partition DABR */
 	/* Do this before re-enabling PMU to avoid P7 DABR corruption bug */
 	lwz	r5,VCPU_DABRX(r4)
 	ld	r6,VCPU_DABR(r4)
 	mtspr	SPRN_DABRX,r5
 	mtspr	SPRN_DABR,r6
 	isync
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Branch around the call if both CPU_FTR_TM and
  * CPU_FTR_P9_TM_HV_ASSIST are off.
  */
 BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
 	 */
 	mr      r3, r4
 	ld      r4, VCPU_MSR(r3)
 	bl	kvmppc_restore_tm_hv
 	ld	r4, HSTATE_KVM_VCPU(r13)
 91:
 #endif

 	/* Load guest PMU registers */
 	/* R4 is live here (vcpu pointer) */
 	li	r3, 1
 	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
 	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable ints */
 	isync
 BEGIN_FTR_SECTION
 	ld	r3, VCPU_MMCR(r4)
 	andi.	r5, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO
 	cmpwi	r5, MMCR0_PMAO
 	beql	kvmppc_fix_pmao
 END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)
 	lwz	r3, VCPU_PMC(r4)	/* always load up guest PMU registers */
 	lwz	r5, VCPU_PMC + 4(r4)	/* to prevent information leak */
 	lwz	r6, VCPU_PMC + 8(r4)
 	lwz	r7, VCPU_PMC + 12(r4)
 	lwz	r8, VCPU_PMC + 16(r4)
 	lwz	r9, VCPU_PMC + 20(r4)
 	mtspr	SPRN_PMC1, r3
 	mtspr	SPRN_PMC2, r5
 	mtspr	SPRN_PMC3, r6
 	mtspr	SPRN_PMC4, r7
 	mtspr	SPRN_PMC5, r8
 	mtspr	SPRN_PMC6, r9
 	ld	r3, VCPU_MMCR(r4)
 	ld	r5, VCPU_MMCR + 8(r4)
 	ld	r6, VCPU_MMCR + 16(r4)
 	ld	r7, VCPU_SIAR(r4)
 	ld	r8, VCPU_SDAR(r4)
 	mtspr	SPRN_MMCR1, r5
 	mtspr	SPRN_MMCRA, r6
 	mtspr	SPRN_SIAR, r7
 	mtspr	SPRN_SDAR, r8
 BEGIN_FTR_SECTION
 	ld	r5, VCPU_MMCR + 24(r4)
 	ld	r6, VCPU_SIER(r4)
 	mtspr	SPRN_MMCR2, r5
 	mtspr	SPRN_SIER, r6
 BEGIN_FTR_SECTION_NESTED(96)
 	lwz	r7, VCPU_PMC + 24(r4)
 	lwz	r8, VCPU_PMC + 28(r4)
 	ld	r9, VCPU_MMCR + 32(r4)
 	mtspr	SPRN_SPMC1, r7
 	mtspr	SPRN_SPMC2, r8
 	mtspr	SPRN_MMCRS, r9
 END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	mtspr	SPRN_MMCR0, r3
 	isync

 	/* Load up FP, VMX and VSX registers */
 	bl	kvmppc_load_fp

 	ld	r14, VCPU_GPR(R14)(r4)
 	ld	r15, VCPU_GPR(R15)(r4)
 	ld	r16, VCPU_GPR(R16)(r4)
 	ld	r17, VCPU_GPR(R17)(r4)
 	ld	r18, VCPU_GPR(R18)(r4)
 	ld	r19, VCPU_GPR(R19)(r4)
 	ld	r20, VCPU_GPR(R20)(r4)
 	ld	r21, VCPU_GPR(R21)(r4)
 	ld	r22, VCPU_GPR(R22)(r4)
 	ld	r23, VCPU_GPR(R23)(r4)
 	ld	r24, VCPU_GPR(R24)(r4)
 	ld	r25, VCPU_GPR(R25)(r4)
 	ld	r26, VCPU_GPR(R26)(r4)
 	ld	r27, VCPU_GPR(R27)(r4)
 	ld	r28, VCPU_GPR(R28)(r4)
 	ld	r29, VCPU_GPR(R29)(r4)
 	ld	r30, VCPU_GPR(R30)(r4)
 	ld	r31, VCPU_GPR(R31)(r4)

 	/* Switch DSCR to guest value */
 	ld	r5, VCPU_DSCR(r4)
 	mtspr	SPRN_DSCR, r5

 BEGIN_FTR_SECTION
 	/* Skip next section on POWER7 */
 	b	8f
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	/* Load up POWER8-specific registers */
 	ld	r5, VCPU_IAMR(r4)
 	lwz	r6, VCPU_PSPB(r4)
 	ld	r7, VCPU_FSCR(r4)
 	mtspr	SPRN_IAMR, r5
 	mtspr	SPRN_PSPB, r6
 	mtspr	SPRN_FSCR, r7
 	ld	r5, VCPU_DAWR(r4)
 	ld	r6, VCPU_DAWRX(r4)
 	ld	r7, VCPU_CIABR(r4)
 	ld	r8, VCPU_TAR(r4)
 	/*
 	 * Handle broken DAWR case by not writing it. This means we
 	 * can still store the DAWR register for migration.
 	 */
 BEGIN_FTR_SECTION
 	mtspr	SPRN_DAWR, r5
 	mtspr	SPRN_DAWRX, r6
 END_FTR_SECTION_IFSET(CPU_FTR_DAWR)
 	mtspr	SPRN_CIABR, r7
 	mtspr	SPRN_TAR, r8
 	ld	r5, VCPU_IC(r4)
 	ld	r8, VCPU_EBBHR(r4)
 	mtspr	SPRN_IC, r5
 	mtspr	SPRN_EBBHR, r8
 	ld	r5, VCPU_EBBRR(r4)
 	ld	r6, VCPU_BESCR(r4)
 	lwz	r7, VCPU_GUEST_PID(r4)
 	ld	r8, VCPU_WORT(r4)
 	mtspr	SPRN_EBBRR, r5
 	mtspr	SPRN_BESCR, r6
 	mtspr	SPRN_PID, r7
 	mtspr	SPRN_WORT, r8
 BEGIN_FTR_SECTION
 	/* POWER8-only registers */
 	ld	r5, VCPU_TCSCR(r4)
 	ld	r6, VCPU_ACOP(r4)
 	ld	r7, VCPU_CSIGR(r4)
 	ld	r8, VCPU_TACR(r4)
 	mtspr	SPRN_TCSCR, r5
 	mtspr	SPRN_ACOP, r6
 	mtspr	SPRN_CSIGR, r7
 	mtspr	SPRN_TACR, r8
 	nop
 FTR_SECTION_ELSE
 	/* POWER9-only registers */
 	ld	r5, VCPU_TID(r4)
 	ld	r6, VCPU_PSSCR(r4)
 	lbz	r8, HSTATE_FAKE_SUSPEND(r13)
 	oris	r6, r6, PSSCR_EC@h	/* This makes stop trap to HV */
 	rldimi	r6, r8, PSSCR_FAKE_SUSPEND_LG, 63 - PSSCR_FAKE_SUSPEND_LG
 	ld	r7, VCPU_HFSCR(r4)
 	mtspr	SPRN_TIDR, r5
 	mtspr	SPRN_PSSCR, r6
 	mtspr	SPRN_HFSCR, r7
 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 8:

 	ld	r5, VCPU_SPRG0(r4)
 	ld	r6, VCPU_SPRG1(r4)
 	ld	r7, VCPU_SPRG2(r4)
 	ld	r8, VCPU_SPRG3(r4)
 	mtspr	SPRN_SPRG0, r5
 	mtspr	SPRN_SPRG1, r6
 	mtspr	SPRN_SPRG2, r7
 	mtspr	SPRN_SPRG3, r8

 	/* Load up DAR and DSISR */
 	ld	r5, VCPU_DAR(r4)
 	lwz	r6, VCPU_DSISR(r4)
 	mtspr	SPRN_DAR, r5
 	mtspr	SPRN_DSISR, r6

 	/* Restore AMR and UAMOR, set AMOR to all 1s */
 	ld	r5,VCPU_AMR(r4)
 	ld	r6,VCPU_UAMOR(r4)
 	li	r7,-1
 	mtspr	SPRN_AMR,r5
 	mtspr	SPRN_UAMOR,r6
 	mtspr	SPRN_AMOR,r7

 	/* Restore state of CTRL run bit; assume 1 on entry */
 	lwz	r5,VCPU_CTRL(r4)
 	andi.	r5,r5,1
 	bne	4f
 	mfspr	r6,SPRN_CTRLF
 	clrrdi	r6,r6,1
 	mtspr	SPRN_CTRLT,r6
 4:
 	/* Secondary threads wait for primary to have done partition switch */
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	lbz	r6, HSTATE_PTID(r13)
 	cmpwi	r6, 0
 	beq	21f
 	lbz	r0, VCORE_IN_GUEST(r5)
 	cmpwi	r0, 0
 	bne	21f
 	HMT_LOW
 20:	lwz	r3, VCORE_ENTRY_EXIT(r5)
 	cmpwi	r3, 0x100
 	bge	no_switch_exit
 	lbz	r0, VCORE_IN_GUEST(r5)
 	cmpwi	r0, 0
 	beq	20b
 	HMT_MEDIUM
 21:
 	/* Set LPCR. */
 	ld	r8,VCORE_LPCR(r5)
 	mtspr	SPRN_LPCR,r8
 	isync

 	/*
 	 * Set the decrementer to the guest decrementer.
 	 */
 	ld	r8,VCPU_DEC_EXPIRES(r4)
 	/* r8 is a host timebase value here, convert to guest TB */
 	ld	r5,HSTATE_KVM_VCORE(r13)
 	ld	r6,VCORE_TB_OFFSET_APPL(r5)
 	add	r8,r8,r6
 	mftb	r7
 	subf	r3,r7,r8
 	mtspr	SPRN_DEC,r3

 	/* Check if HDEC expires soon */
 	mfspr	r3, SPRN_HDEC
 	EXTEND_HDEC(r3)
 	cmpdi	r3, 512		/* 1 microsecond */
 	blt	hdec_soon

 	/* For hash guest, clear out and reload the SLB */
 	ld	r6, VCPU_KVM(r4)
 	lbz	r0, KVM_RADIX(r6)
 	cmpwi	r0, 0
 	bne	9f
 	li	r6, 0
 	slbmte	r6, r6
 	slbia
 	ptesync

 	/* Load up guest SLB entries (N.B. slb_max will be 0 for radix) */
 	lwz	r5,VCPU_SLB_MAX(r4)
 	cmpwi	r5,0
 	beq	9f
 	mtctr	r5
 	addi	r6,r4,VCPU_SLB
 1:	ld	r8,VCPU_SLB_E(r6)
 	ld	r9,VCPU_SLB_V(r6)
 	slbmte	r9,r8
 	addi	r6,r6,VCPU_SLB_SIZE
 	bdnz	1b
 9:

 #ifdef CONFIG_KVM_XICS
 	/* We are entering the guest on that thread, push VCPU to XIVE */
 	ld	r10, HSTATE_XIVE_TIMA_PHYS(r13)
 	cmpldi	cr0, r10, 0
 	beq	no_xive
 	ld	r11, VCPU_XIVE_SAVED_STATE(r4)
 	li	r9, TM_QW1_OS
 	eieio
 	stdcix	r11,r9,r10
 	lwz	r11, VCPU_XIVE_CAM_WORD(r4)
 	li	r9, TM_QW1_OS + TM_WORD2
 	stwcix	r11,r9,r10
 	li	r9, 1
 	stb	r9, VCPU_XIVE_PUSHED(r4)
 	eieio

 	/*
 	 * We clear the irq_pending flag. There is a small chance of a
 	 * race vs. the escalation interrupt happening on another
 	 * processor setting it again, but the only consequence is to
 	 * cause a spurrious wakeup on the next H_CEDE which is not an
 	 * issue.
 	 */
 	li	r0,0
 	stb	r0, VCPU_IRQ_PENDING(r4)

 	/*
 	 * In single escalation mode, if the escalation interrupt is
 	 * on, we mask it.
 	 */
 	lbz	r0, VCPU_XIVE_ESC_ON(r4)
 	cmpwi	r0,0
 	beq	1f
 	ld	r10, VCPU_XIVE_ESC_RADDR(r4)
 	li	r9, XIVE_ESB_SET_PQ_01
 	ldcix	r0, r10, r9
 	sync

 	/* We have a possible subtle race here: The escalation interrupt might
 	 * have fired and be on its way to the host queue while we mask it,
 	 * and if we unmask it early enough (re-cede right away), there is
 	 * a theorical possibility that it fires again, thus landing in the
 	 * target queue more than once which is a big no-no.
 	 *
 	 * Fortunately, solving this is rather easy. If the above load setting
 	 * PQ to 01 returns a previous value where P is set, then we know the
 	 * escalation interrupt is somewhere on its way to the host. In that
 	 * case we simply don't clear the xive_esc_on flag below. It will be
 	 * eventually cleared by the handler for the escalation interrupt.
 	 *
 	 * Then, when doing a cede, we check that flag again before re-enabling
 	 * the escalation interrupt, and if set, we abort the cede.
 	 */
 	andi.	r0, r0, XIVE_ESB_VAL_P
 	bne-	1f

 	/* Now P is 0, we can clear the flag */
 	li	r0, 0
 	stb	r0, VCPU_XIVE_ESC_ON(r4)
 1:
 no_xive:
 #endif /* CONFIG_KVM_XICS */

 deliver_guest_interrupt:
 	ld	r6, VCPU_CTR(r4)
 	ld	r7, VCPU_XER(r4)

 	mtctr	r6
 	mtxer	r7

 kvmppc_cede_reentry:		/* r4 = vcpu, r13 = paca */
 	ld	r10, VCPU_PC(r4)
 	ld	r11, VCPU_MSR(r4)
 	ld	r6, VCPU_SRR0(r4)
 	ld	r7, VCPU_SRR1(r4)
 	mtspr	SPRN_SRR0, r6
 	mtspr	SPRN_SRR1, r7

 	/* r11 = vcpu->arch.msr & ~MSR_HV */
 	rldicl	r11, r11, 63 - MSR_HV_LG, 1
 	rotldi	r11, r11, 1 + MSR_HV_LG
 	ori	r11, r11, MSR_ME

 	/* Check if we can deliver an external or decrementer interrupt now */
 	ld	r0, VCPU_PENDING_EXC(r4)
 	rldicl	r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL_LEVEL, 63
 	cmpdi	cr1, r0, 0
 	andi.	r8, r11, MSR_EE
 	mfspr	r8, SPRN_LPCR
 	/* Insert EXTERNAL_LEVEL bit into LPCR at the MER bit position */
 	rldimi	r8, r0, LPCR_MER_SH, 63 - LPCR_MER_SH
 	mtspr	SPRN_LPCR, r8
 	isync
 	beq	5f
 	li	r0, BOOK3S_INTERRUPT_EXTERNAL
 	bne	cr1, 12f
 	mfspr	r0, SPRN_DEC
 BEGIN_FTR_SECTION
 	/* On POWER9 check whether the guest has large decrementer enabled */
 	andis.	r8, r8, LPCR_LD@h
 	bne	15f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r0, r0
 15:	cmpdi	r0, 0
 	li	r0, BOOK3S_INTERRUPT_DECREMENTER
 	bge	5f

 12:	mtspr	SPRN_SRR0, r10
 	mr	r10,r0
 	mtspr	SPRN_SRR1, r11
 	mr	r9, r4
 	bl	kvmppc_msr_interrupt
 5:
 BEGIN_FTR_SECTION
 	b	fast_guest_return
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	/* On POWER9, check for pending doorbell requests */
 	lbz	r0, VCPU_DBELL_REQ(r4)
 	cmpwi	r0, 0
 	beq	fast_guest_return
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	/* Set DPDES register so the CPU will take a doorbell interrupt */
 	li	r0, 1
 	mtspr	SPRN_DPDES, r0
 	std	r0, VCORE_DPDES(r5)
 	/* Make sure other cpus see vcore->dpdes set before dbell req clear */
 	lwsync
 	/* Clear the pending doorbell request */
 	li	r0, 0
 	stb	r0, VCPU_DBELL_REQ(r4)

 /*
  * Required state:
  * R4 = vcpu
  * R10: value for HSRR0
  * R11: value for HSRR1
  * R13 = PACA
  */
 fast_guest_return:
 	li	r0,0
 	stb	r0,VCPU_CEDED(r4)	/* cancel cede */
 	mtspr	SPRN_HSRR0,r10
 	mtspr	SPRN_HSRR1,r11

 	/* Activate guest mode, so faults get handled by KVM */
 	li	r9, KVM_GUEST_MODE_GUEST_HV
 	stb	r9, HSTATE_IN_GUEST(r13)

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	/* Accumulate timing */
 	addi	r3, r4, VCPU_TB_GUEST
 	bl	kvmhv_accumulate_time
 #endif

 	/* Enter guest */

 BEGIN_FTR_SECTION
 	ld	r5, VCPU_CFAR(r4)
 	mtspr	SPRN_CFAR, r5
 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 BEGIN_FTR_SECTION
 	ld	r0, VCPU_PPR(r4)
 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)

 	ld	r5, VCPU_LR(r4)
 	lwz	r6, VCPU_CR(r4)
 	mtlr	r5
 	mtcr	r6

 	ld	r1, VCPU_GPR(R1)(r4)
 	ld	r2, VCPU_GPR(R2)(r4)
 	ld	r3, VCPU_GPR(R3)(r4)
 	ld	r5, VCPU_GPR(R5)(r4)
 	ld	r6, VCPU_GPR(R6)(r4)
 	ld	r7, VCPU_GPR(R7)(r4)
 	ld	r8, VCPU_GPR(R8)(r4)
 	ld	r9, VCPU_GPR(R9)(r4)
 	ld	r10, VCPU_GPR(R10)(r4)
 	ld	r11, VCPU_GPR(R11)(r4)
 	ld	r12, VCPU_GPR(R12)(r4)
 	ld	r13, VCPU_GPR(R13)(r4)

 BEGIN_FTR_SECTION
 	mtspr	SPRN_PPR, r0
 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)

 /* Move canary into DSISR to check for later */
 BEGIN_FTR_SECTION
 	li	r0, 0x7fff
 	mtspr	SPRN_HDSISR, r0
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)

 	ld	r0, VCPU_GPR(R0)(r4)
 	ld	r4, VCPU_GPR(R4)(r4)
 	HRFI_TO_GUEST
 	b	.

 secondary_too_late:
 	li	r12, 0
 	stw	r12, STACK_SLOT_TRAP(r1)
 	cmpdi	r4, 0
 	beq	11f
 	stw	r12, VCPU_TRAP(r4)
 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r4, VCPU_TB_RMEXIT
 	bl	kvmhv_accumulate_time
 #endif
 11:	b	kvmhv_switch_to_host

 no_switch_exit:
 	HMT_MEDIUM
 	li	r12, 0
 	b	12f
 hdec_soon:
 	li	r12, BOOK3S_INTERRUPT_HV_DECREMENTER
 12:	stw	r12, VCPU_TRAP(r4)
 	mr	r9, r4
 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r4, VCPU_TB_RMEXIT
 	bl	kvmhv_accumulate_time
 #endif
 	b	guest_bypass

 /******************************************************************************
  *                                                                            *
  *                               Exit code                                    *
  *                                                                            *
  *****************************************************************************/

 /*
  * We come here from the first-level interrupt handlers.
  */
 	.globl	kvmppc_interrupt_hv
 kvmppc_interrupt_hv:
 	/*
 	 * Register contents:
 	 * R12		= (guest CR << 32) | interrupt vector
 	 * R13		= PACA
 	 * guest R12 saved in shadow VCPU SCRATCH0
 	 * guest CTR saved in shadow VCPU SCRATCH1 if RELOCATABLE
 	 * guest R13 saved in SPRN_SCRATCH0
 	 */
 	std	r9, HSTATE_SCRATCH2(r13)
 	lbz	r9, HSTATE_IN_GUEST(r13)
 	cmpwi	r9, KVM_GUEST_MODE_HOST_HV
 	beq	kvmppc_bad_host_intr
 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
 	cmpwi	r9, KVM_GUEST_MODE_GUEST
 	ld	r9, HSTATE_SCRATCH2(r13)
 	beq	kvmppc_interrupt_pr
 #endif
 	/* We're now back in the host but in guest MMU context */
 	li	r9, KVM_GUEST_MODE_HOST_HV
 	stb	r9, HSTATE_IN_GUEST(r13)

 	ld	r9, HSTATE_KVM_VCPU(r13)

 	/* Save registers */

 	std	r0, VCPU_GPR(R0)(r9)
 	std	r1, VCPU_GPR(R1)(r9)
 	std	r2, VCPU_GPR(R2)(r9)
 	std	r3, VCPU_GPR(R3)(r9)
 	std	r4, VCPU_GPR(R4)(r9)
 	std	r5, VCPU_GPR(R5)(r9)
 	std	r6, VCPU_GPR(R6)(r9)
 	std	r7, VCPU_GPR(R7)(r9)
 	std	r8, VCPU_GPR(R8)(r9)
 	ld	r0, HSTATE_SCRATCH2(r13)
 	std	r0, VCPU_GPR(R9)(r9)
 	std	r10, VCPU_GPR(R10)(r9)
 	std	r11, VCPU_GPR(R11)(r9)
 	ld	r3, HSTATE_SCRATCH0(r13)
 	std	r3, VCPU_GPR(R12)(r9)
 	/* CR is in the high half of r12 */
 	srdi	r4, r12, 32
 	stw	r4, VCPU_CR(r9)
 BEGIN_FTR_SECTION
 	ld	r3, HSTATE_CFAR(r13)
 	std	r3, VCPU_CFAR(r9)
 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 BEGIN_FTR_SECTION
 	ld	r4, HSTATE_PPR(r13)
 	std	r4, VCPU_PPR(r9)
 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)

 	/* Restore R1/R2 so we can handle faults */
 	ld	r1, HSTATE_HOST_R1(r13)
 	ld	r2, PACATOC(r13)

 	mfspr	r10, SPRN_SRR0
 	mfspr	r11, SPRN_SRR1
 	std	r10, VCPU_SRR0(r9)
 	std	r11, VCPU_SRR1(r9)
 	/* trap is in the low half of r12, clear CR from the high half */
 	clrldi	r12, r12, 32
 	andi.	r0, r12, 2		/* need to read HSRR0/1? */
 	beq	1f
 	mfspr	r10, SPRN_HSRR0
 	mfspr	r11, SPRN_HSRR1
 	clrrdi	r12, r12, 2
 1:	std	r10, VCPU_PC(r9)
 	std	r11, VCPU_MSR(r9)

 	GET_SCRATCH0(r3)
 	mflr	r4
 	std	r3, VCPU_GPR(R13)(r9)
 	std	r4, VCPU_LR(r9)

 	stw	r12,VCPU_TRAP(r9)

 	/*
 	 * Now that we have saved away SRR0/1 and HSRR0/1,
 	 * interrupts are recoverable in principle, so set MSR_RI.
 	 * This becomes important for relocation-on interrupts from
 	 * the guest, which we can get in radix mode on POWER9.
 	 */
 	li	r0, MSR_RI
 	mtmsrd	r0, 1

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r9, VCPU_TB_RMINTR
 	mr	r4, r9
 	bl	kvmhv_accumulate_time
 	ld	r5, VCPU_GPR(R5)(r9)
 	ld	r6, VCPU_GPR(R6)(r9)
 	ld	r7, VCPU_GPR(R7)(r9)
 	ld	r8, VCPU_GPR(R8)(r9)
 #endif

 	/* Save HEIR (HV emulation assist reg) in emul_inst
 	   if this is an HEI (HV emulation interrupt, e40) */
 	li	r3,KVM_INST_FETCH_FAILED
 	stw	r3,VCPU_LAST_INST(r9)
 	cmpwi	r12,BOOK3S_INTERRUPT_H_EMUL_ASSIST
 	bne	11f
 	mfspr	r3,SPRN_HEIR
 11:	stw	r3,VCPU_HEIR(r9)

 	/* these are volatile across C function calls */
 #ifdef CONFIG_RELOCATABLE
 	ld	r3, HSTATE_SCRATCH1(r13)
 	mtctr	r3
 #else
 	mfctr	r3
 #endif
 	mfxer	r4
 	std	r3, VCPU_CTR(r9)
 	std	r4, VCPU_XER(r9)

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	/* For softpatch interrupt, go off and do TM instruction emulation */
 	cmpwi	r12, BOOK3S_INTERRUPT_HV_SOFTPATCH
 	beq	kvmppc_tm_emul
 #endif

 	/* If this is a page table miss then see if it's theirs or ours */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_DATA_STORAGE
 	beq	kvmppc_hdsi
 	cmpwi	r12, BOOK3S_INTERRUPT_H_INST_STORAGE
 	beq	kvmppc_hisi

 	/* See if this is a leftover HDEC interrupt */
 	cmpwi	r12,BOOK3S_INTERRUPT_HV_DECREMENTER
 	bne	2f
 	mfspr	r3,SPRN_HDEC
 	EXTEND_HDEC(r3)
 	cmpdi	r3,0
 	mr	r4,r9
 	bge	fast_guest_return
 2:
 	/* See if this is an hcall we can handle in real mode */
 	cmpwi	r12,BOOK3S_INTERRUPT_SYSCALL
 	beq	hcall_try_real_mode

 	/* Hypervisor doorbell - exit only if host IPI flag set */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_DOORBELL
 	bne	3f
 BEGIN_FTR_SECTION
 	PPC_MSGSYNC
 	lwsync
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	lbz	r0, HSTATE_HOST_IPI(r13)
 	cmpwi	r0, 0
 	beq	4f
 	b	guest_exit_cont
 3:
 	/* If it's a hypervisor facility unavailable interrupt, save HFSCR */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_FAC_UNAVAIL
 	bne	14f
 	mfspr	r3, SPRN_HFSCR
 	std	r3, VCPU_HFSCR(r9)
 	b	guest_exit_cont
 14:
 	/* External interrupt ? */
 	cmpwi	r12, BOOK3S_INTERRUPT_EXTERNAL
 	bne+	guest_exit_cont

 	/* External interrupt, first check for host_ipi. If this is
 	 * set, we know the host wants us out so let's do it now
 	 */
 	bl	kvmppc_read_intr

 	/*
 	 * Restore the active volatile registers after returning from
 	 * a C function.
 	 */
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	li	r12, BOOK3S_INTERRUPT_EXTERNAL

 	/*
 	 * kvmppc_read_intr return codes:
 	 *
 	 * Exit to host (r3 > 0)
 	 *   1 An interrupt is pending that needs to be handled by the host
 	 *     Exit guest and return to host by branching to guest_exit_cont
 	 *
 	 *   2 Passthrough that needs completion in the host
 	 *     Exit guest and return to host by branching to guest_exit_cont
 	 *     However, we also set r12 to BOOK3S_INTERRUPT_HV_RM_HARD
 	 *     to indicate to the host to complete handling the interrupt
 	 *
 	 * Before returning to guest, we check if any CPU is heading out
 	 * to the host and if so, we head out also. If no CPUs are heading
 	 * check return values <= 0.
 	 *
 	 * Return to guest (r3 <= 0)
 	 *  0 No external interrupt is pending
 	 * -1 A guest wakeup IPI (which has now been cleared)
 	 *    In either case, we return to guest to deliver any pending
 	 *    guest interrupts.
 	 *
 	 * -2 A PCI passthrough external interrupt was handled
 	 *    (interrupt was delivered directly to guest)
 	 *    Return to guest to deliver any pending guest interrupts.
 	 */

 	cmpdi	r3, 1
 	ble	1f

 	/* Return code = 2 */
 	li	r12, BOOK3S_INTERRUPT_HV_RM_HARD
 	stw	r12, VCPU_TRAP(r9)
 	b	guest_exit_cont

 1:	/* Return code <= 1 */
 	cmpdi	r3, 0
 	bgt	guest_exit_cont

 	/* Return code <= 0 */
 4:	ld	r5, HSTATE_KVM_VCORE(r13)
 	lwz	r0, VCORE_ENTRY_EXIT(r5)
 	cmpwi	r0, 0x100
 	mr	r4, r9
 	blt	deliver_guest_interrupt

 guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 	/* Save more register state  */
 	mfdar	r6
 	mfdsisr	r7
 	std	r6, VCPU_DAR(r9)
 	stw	r7, VCPU_DSISR(r9)
 	/* don't overwrite fault_dar/fault_dsisr if HDSI */
 	cmpwi	r12,BOOK3S_INTERRUPT_H_DATA_STORAGE
 	beq	mc_cont
 	std	r6, VCPU_FAULT_DAR(r9)
 	stw	r7, VCPU_FAULT_DSISR(r9)

 	/* See if it is a machine check */
 	cmpwi	r12, BOOK3S_INTERRUPT_MACHINE_CHECK
 	beq	machine_check_realmode
 mc_cont:
 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r9, VCPU_TB_RMEXIT
 	mr	r4, r9
 	bl	kvmhv_accumulate_time
 #endif
 #ifdef CONFIG_KVM_XICS
 	/* We are exiting, pull the VP from the XIVE */
 	lbz	r0, VCPU_XIVE_PUSHED(r9)
 	cmpwi	cr0, r0, 0
 	beq	1f
 	li	r7, TM_SPC_PULL_OS_CTX
 	li	r6, TM_QW1_OS
 	mfmsr	r0
 	andi.	r0, r0, MSR_DR		/* in real mode? */
 	beq	2f
 	ld	r10, HSTATE_XIVE_TIMA_VIRT(r13)
 	cmpldi	cr0, r10, 0
 	beq	1f
 	/* First load to pull the context, we ignore the value */
 	eieio
 	lwzx	r11, r7, r10
 	/* Second load to recover the context state (Words 0 and 1) */
 	ldx	r11, r6, r10
 	b	3f
 2:	ld	r10, HSTATE_XIVE_TIMA_PHYS(r13)
 	cmpldi	cr0, r10, 0
 	beq	1f
 	/* First load to pull the context, we ignore the value */
 	eieio
 	lwzcix	r11, r7, r10
 	/* Second load to recover the context state (Words 0 and 1) */
 	ldcix	r11, r6, r10
 3:	std	r11, VCPU_XIVE_SAVED_STATE(r9)
 	/* Fixup some of the state for the next load */
 	li	r10, 0
 	li	r0, 0xff
 	stb	r10, VCPU_XIVE_PUSHED(r9)
 	stb	r10, (VCPU_XIVE_SAVED_STATE+3)(r9)
 	stb	r0, (VCPU_XIVE_SAVED_STATE+4)(r9)
 	eieio
 1:
 #endif /* CONFIG_KVM_XICS */

 	/* For hash guest, read the guest SLB and save it away */
 	ld	r5, VCPU_KVM(r9)
 	lbz	r0, KVM_RADIX(r5)
 	li	r5, 0
 	cmpwi	r0, 0
 	bne	3f			/* for radix, save 0 entries */
 	lwz	r0,VCPU_SLB_NR(r9)	/* number of entries in SLB */
 	mtctr	r0
 	li	r6,0
 	addi	r7,r9,VCPU_SLB
 1:	slbmfee	r8,r6
 	andis.	r0,r8,SLB_ESID_V@h
 	beq	2f
 	add	r8,r8,r6		/* put index in */
 	slbmfev	r3,r6
 	std	r8,VCPU_SLB_E(r7)
 	std	r3,VCPU_SLB_V(r7)
 	addi	r7,r7,VCPU_SLB_SIZE
 	addi	r5,r5,1
 2:	addi	r6,r6,1
 	bdnz	1b
 	/* Finally clear out the SLB */
 	li	r0,0
 	slbmte	r0,r0
 	slbia
 	ptesync
 3:	stw	r5,VCPU_SLB_MAX(r9)

 	/* load host SLB entries */
 BEGIN_MMU_FTR_SECTION
 	b	0f
 END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 	ld	r8,PACA_SLBSHADOWPTR(r13)

 	.rept	SLB_NUM_BOLTED
 	li	r3, SLBSHADOW_SAVEAREA
 	LDX_BE	r5, r8, r3
 	addi	r3, r3, 8
 	LDX_BE	r6, r8, r3
 	andis.	r7,r5,SLB_ESID_V@h
 	beq	1f
 	slbmte	r6,r5
 1:	addi	r8,r8,16
 	.endr
 0:

 guest_bypass:
 	stw	r12, STACK_SLOT_TRAP(r1)

 	/* Save DEC */
 	/* Do this before kvmhv_commence_exit so we know TB is guest TB */
 	ld	r3, HSTATE_KVM_VCORE(r13)
 	mfspr	r5,SPRN_DEC
 	mftb	r6
 	/* On P9, if the guest has large decr enabled, don't sign extend */
 BEGIN_FTR_SECTION
 	ld	r4, VCORE_LPCR(r3)
 	andis.	r4, r4, LPCR_LD@h
 	bne	16f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r5,r5
 16:	add	r5,r5,r6
 	/* r5 is a guest timebase value here, convert to host TB */
 	ld	r4,VCORE_TB_OFFSET_APPL(r3)
 	subf	r5,r4,r5
 	std	r5,VCPU_DEC_EXPIRES(r9)

 	/* Increment exit count, poke other threads to exit */
 	mr 	r3, r12
 	bl	kvmhv_commence_exit
 	nop
 	ld	r9, HSTATE_KVM_VCPU(r13)

 	/* Stop others sending VCPU interrupts to this physical CPU */
 	li	r0, -1
 	stw	r0, VCPU_CPU(r9)
 	stw	r0, VCPU_THREAD_CPU(r9)

 	/* Save guest CTRL register, set runlatch to 1 */
 	mfspr	r6,SPRN_CTRLF
 	stw	r6,VCPU_CTRL(r9)
 	andi.	r0,r6,1
 	bne	4f
 	ori	r6,r6,1
 	mtspr	SPRN_CTRLT,r6
 4:
 	/*
 	 * Save the guest PURR/SPURR
 	 */
 	mfspr	r5,SPRN_PURR
 	mfspr	r6,SPRN_SPURR
 	ld	r7,VCPU_PURR(r9)
 	ld	r8,VCPU_SPURR(r9)
 	std	r5,VCPU_PURR(r9)
 	std	r6,VCPU_SPURR(r9)
 	subf	r5,r7,r5
 	subf	r6,r8,r6

 	/*
 	 * Restore host PURR/SPURR and add guest times
 	 * so that the time in the guest gets accounted.
 	 */
 	ld	r3,HSTATE_PURR(r13)
 	ld	r4,HSTATE_SPURR(r13)
 	add	r3,r3,r5
 	add	r4,r4,r6
 	mtspr	SPRN_PURR,r3
 	mtspr	SPRN_SPURR,r4

 BEGIN_FTR_SECTION
 	b	8f
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	/* Save POWER8-specific registers */
 	mfspr	r5, SPRN_IAMR
 	mfspr	r6, SPRN_PSPB
 	mfspr	r7, SPRN_FSCR
 	std	r5, VCPU_IAMR(r9)
 	stw	r6, VCPU_PSPB(r9)
 	std	r7, VCPU_FSCR(r9)
 	mfspr	r5, SPRN_IC
 	mfspr	r7, SPRN_TAR
 	std	r5, VCPU_IC(r9)
 	std	r7, VCPU_TAR(r9)
 	mfspr	r8, SPRN_EBBHR
 	std	r8, VCPU_EBBHR(r9)
 	mfspr	r5, SPRN_EBBRR
 	mfspr	r6, SPRN_BESCR
 	mfspr	r7, SPRN_PID
 	mfspr	r8, SPRN_WORT
 	std	r5, VCPU_EBBRR(r9)
 	std	r6, VCPU_BESCR(r9)
 	stw	r7, VCPU_GUEST_PID(r9)
 	std	r8, VCPU_WORT(r9)
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_TCSCR
 	mfspr	r6, SPRN_ACOP
 	mfspr	r7, SPRN_CSIGR
 	mfspr	r8, SPRN_TACR
 	std	r5, VCPU_TCSCR(r9)
 	std	r6, VCPU_ACOP(r9)
 	std	r7, VCPU_CSIGR(r9)
 	std	r8, VCPU_TACR(r9)
 FTR_SECTION_ELSE
 	mfspr	r5, SPRN_TIDR
 	mfspr	r6, SPRN_PSSCR
 	std	r5, VCPU_TID(r9)
 	rldicl	r6, r6, 4, 50		/* r6 &= PSSCR_GUEST_VIS */
 	rotldi	r6, r6, 60
 	std	r6, VCPU_PSSCR(r9)
 	/* Restore host HFSCR value */
 	ld	r7, STACK_SLOT_HFSCR(r1)
 	mtspr	SPRN_HFSCR, r7
 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	/*
 	 * Restore various registers to 0, where non-zero values
 	 * set by the guest could disrupt the host.
 	 */
 	li	r0, 0
 	mtspr	SPRN_PSPB, r0
 	mtspr	SPRN_WORT, r0
 BEGIN_FTR_SECTION
 	mtspr	SPRN_IAMR, r0
 	mtspr	SPRN_TCSCR, r0
 	/* Set MMCRS to 1<<31 to freeze and disable the SPMC counters */
 	li	r0, 1
 	sldi	r0, r0, 31
 	mtspr	SPRN_MMCRS, r0
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 8:

 	/* Save and reset AMR and UAMOR before turning on the MMU */
 	mfspr	r5,SPRN_AMR
 	mfspr	r6,SPRN_UAMOR
 	std	r5,VCPU_AMR(r9)
 	std	r6,VCPU_UAMOR(r9)
 	li	r6,0
 	mtspr	SPRN_AMR,r6
 	mtspr	SPRN_UAMOR, r6

 	/* Switch DSCR back to host value */
 	mfspr	r8, SPRN_DSCR
 	ld	r7, HSTATE_DSCR(r13)
 	std	r8, VCPU_DSCR(r9)
 	mtspr	SPRN_DSCR, r7

 	/* Save non-volatile GPRs */
 	std	r14, VCPU_GPR(R14)(r9)
 	std	r15, VCPU_GPR(R15)(r9)
 	std	r16, VCPU_GPR(R16)(r9)
 	std	r17, VCPU_GPR(R17)(r9)
 	std	r18, VCPU_GPR(R18)(r9)
 	std	r19, VCPU_GPR(R19)(r9)
 	std	r20, VCPU_GPR(R20)(r9)
 	std	r21, VCPU_GPR(R21)(r9)
 	std	r22, VCPU_GPR(R22)(r9)
 	std	r23, VCPU_GPR(R23)(r9)
 	std	r24, VCPU_GPR(R24)(r9)
 	std	r25, VCPU_GPR(R25)(r9)
 	std	r26, VCPU_GPR(R26)(r9)
 	std	r27, VCPU_GPR(R27)(r9)
 	std	r28, VCPU_GPR(R28)(r9)
 	std	r29, VCPU_GPR(R29)(r9)
 	std	r30, VCPU_GPR(R30)(r9)
 	std	r31, VCPU_GPR(R31)(r9)

 	/* Save SPRGs */
 	mfspr	r3, SPRN_SPRG0
 	mfspr	r4, SPRN_SPRG1
 	mfspr	r5, SPRN_SPRG2
 	mfspr	r6, SPRN_SPRG3
 	std	r3, VCPU_SPRG0(r9)
 	std	r4, VCPU_SPRG1(r9)
 	std	r5, VCPU_SPRG2(r9)
 	std	r6, VCPU_SPRG3(r9)

 	/* save FP state */
 	mr	r3, r9
 	bl	kvmppc_save_fp

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Branch around the call if both CPU_FTR_TM and
  * CPU_FTR_P9_TM_HV_ASSIST are off.
  */
 BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
 	 */
 	mr      r3, r9
 	ld      r4, VCPU_MSR(r3)
 	bl	kvmppc_save_tm_hv
 	ld	r9, HSTATE_KVM_VCPU(r13)
 91:
 #endif

 	/* Increment yield count if they have a VPA */
 	ld	r8, VCPU_VPA(r9)	/* do they have a VPA? */
 	cmpdi	r8, 0
 	beq	25f
 	li	r4, LPPACA_YIELDCOUNT
 	LWZX_BE	r3, r8, r4
 	addi	r3, r3, 1
 	STWX_BE	r3, r8, r4
 	li	r3, 1
 	stb	r3, VCPU_VPA_DIRTY(r9)
 25:
 	/* Save PMU registers if requested */
 	/* r8 and cr0.eq are live here */
 BEGIN_FTR_SECTION
 	/*
 	 * POWER8 seems to have a hardware bug where setting
 	 * MMCR0[PMAE] along with MMCR0[PMC1CE] and/or MMCR0[PMCjCE]
 	 * when some counters are already negative doesn't seem
 	 * to cause a performance monitor alert (and hence interrupt).
 	 * The effect of this is that when saving the PMU state,
 	 * if there is no PMU alert pending when we read MMCR0
 	 * before freezing the counters, but one becomes pending
 	 * before we read the counters, we lose it.
 	 * To work around this, we need a way to freeze the counters
 	 * before reading MMCR0.  Normally, freezing the counters
 	 * is done by writing MMCR0 (to set MMCR0[FC]) which
 	 * unavoidably writes MMCR0[PMA0] as well.  On POWER8,
 	 * we can also freeze the counters using MMCR2, by writing
 	 * 1s to all the counter freeze condition bits (there are
 	 * 9 bits each for 6 counters).
 	 */
 	li	r3, -1			/* set all freeze bits */
 	clrrdi	r3, r3, 10
 	mfspr	r10, SPRN_MMCR2
 	mtspr	SPRN_MMCR2, r3
 	isync
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	li	r3, 1
 	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
 	mfspr	r4, SPRN_MMCR0		/* save MMCR0 */
 	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable ints */
 	mfspr	r6, SPRN_MMCRA
 	/* Clear MMCRA in order to disable SDAR updates */
 	li	r7, 0
 	mtspr	SPRN_MMCRA, r7
 	isync
 	beq	21f			/* if no VPA, save PMU stuff anyway */
 	lbz	r7, LPPACA_PMCINUSE(r8)
 	cmpwi	r7, 0			/* did they ask for PMU stuff to be saved? */
 	bne	21f
 	std	r3, VCPU_MMCR(r9)	/* if not, set saved MMCR0 to FC */
 	b	22f
 21:	mfspr	r5, SPRN_MMCR1
 	mfspr	r7, SPRN_SIAR
 	mfspr	r8, SPRN_SDAR
 	std	r4, VCPU_MMCR(r9)
 	std	r5, VCPU_MMCR + 8(r9)
 	std	r6, VCPU_MMCR + 16(r9)
 BEGIN_FTR_SECTION
 	std	r10, VCPU_MMCR + 24(r9)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	std	r7, VCPU_SIAR(r9)
 	std	r8, VCPU_SDAR(r9)
 	mfspr	r3, SPRN_PMC1
 	mfspr	r4, SPRN_PMC2
 	mfspr	r5, SPRN_PMC3
 	mfspr	r6, SPRN_PMC4
 	mfspr	r7, SPRN_PMC5
 	mfspr	r8, SPRN_PMC6
 	stw	r3, VCPU_PMC(r9)
 	stw	r4, VCPU_PMC + 4(r9)
 	stw	r5, VCPU_PMC + 8(r9)
 	stw	r6, VCPU_PMC + 12(r9)
 	stw	r7, VCPU_PMC + 16(r9)
 	stw	r8, VCPU_PMC + 20(r9)
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_SIER
 	std	r5, VCPU_SIER(r9)
 BEGIN_FTR_SECTION_NESTED(96)
 	mfspr	r6, SPRN_SPMC1
 	mfspr	r7, SPRN_SPMC2
 	mfspr	r8, SPRN_MMCRS
 	stw	r6, VCPU_PMC + 24(r9)
 	stw	r7, VCPU_PMC + 28(r9)
 	std	r8, VCPU_MMCR + 32(r9)
 	lis	r4, 0x8000
 	mtspr	SPRN_MMCRS, r4
 END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 22:

 	/* Restore host values of some registers */
 BEGIN_FTR_SECTION
 	ld	r5, STACK_SLOT_CIABR(r1)
 	ld	r6, STACK_SLOT_DAWR(r1)
 	ld	r7, STACK_SLOT_DAWRX(r1)
 	mtspr	SPRN_CIABR, r5
 	/*
 	 * If the DAWR doesn't work, it's ok to write these here as
 	 * this value should always be zero
 	*/
 	mtspr	SPRN_DAWR, r6
 	mtspr	SPRN_DAWRX, r7
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 BEGIN_FTR_SECTION
 	ld	r5, STACK_SLOT_TID(r1)
 	ld	r6, STACK_SLOT_PSSCR(r1)
 	ld	r7, STACK_SLOT_PID(r1)
 	ld	r8, STACK_SLOT_IAMR(r1)
 	mtspr	SPRN_TIDR, r5
 	mtspr	SPRN_PSSCR, r6
 	mtspr	SPRN_PID, r7
 	mtspr	SPRN_IAMR, r8
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)

 #ifdef CONFIG_PPC_RADIX_MMU
 	/*
 	 * Are we running hash or radix ?
 	 */
 	ld	r5, VCPU_KVM(r9)
 	lbz	r0, KVM_RADIX(r5)
 	cmpwi	cr2, r0, 0
 	beq	cr2, 2f

 	/*
 	 * Radix: do eieio; tlbsync; ptesync sequence in case we
 	 * interrupted the guest between a tlbie and a ptesync.
 	 */
 	eieio
 	tlbsync
 	ptesync

 	/* Radix: Handle the case where the guest used an illegal PID */
 	LOAD_REG_ADDR(r4, mmu_base_pid)
 	lwz	r3, VCPU_GUEST_PID(r9)
 	lwz	r5, 0(r4)
 	cmpw	cr0,r3,r5
 	blt	2f

 	/*
 	 * Illegal PID, the HW might have prefetched and cached in the TLB
 	 * some translations for the  LPID 0 / guest PID combination which
 	 * Linux doesn't know about, so we need to flush that PID out of
 	 * the TLB. First we need to set LPIDR to 0 so tlbiel applies to
 	 * the right context.
 	*/
 	li	r0,0
 	mtspr	SPRN_LPID,r0
 	isync

 	/* Then do a congruence class local flush */
 	ld	r6,VCPU_KVM(r9)
 	lwz	r0,KVM_TLB_SETS(r6)
 	mtctr	r0
 	li	r7,0x400		/* IS field = 0b01 */
 	ptesync
 	sldi	r0,r3,32		/* RS has PID */
 1:	PPC_TLBIEL(7,0,2,1,1)		/* RIC=2, PRS=1, R=1 */
 	addi	r7,r7,0x1000
 	bdnz	1b
 	ptesync

 2:
 #endif /* CONFIG_PPC_RADIX_MMU */

 	/*
 	 * POWER7/POWER8 guest -> host partition switch code.
 	 * We don't have to lock against tlbies but we do
 	 * have to coordinate the hardware threads.
 	 * Here STACK_SLOT_TRAP(r1) contains the trap number.
 	 */
 kvmhv_switch_to_host:
 	/* Secondary threads wait for primary to do partition switch */
 	ld	r5,HSTATE_KVM_VCORE(r13)
 	ld	r4,VCORE_KVM(r5)	/* pointer to struct kvm */
 	lbz	r3,HSTATE_PTID(r13)
 	cmpwi	r3,0
 	beq	15f
 	HMT_LOW
 13:	lbz	r3,VCORE_IN_GUEST(r5)
 	cmpwi	r3,0
 	bne	13b
 	HMT_MEDIUM
 	b	16f

 	/* Primary thread waits for all the secondaries to exit guest */
 15:	lwz	r3,VCORE_ENTRY_EXIT(r5)
 	rlwinm	r0,r3,32-8,0xff
 	clrldi	r3,r3,56
 	cmpw	r3,r0
 	bne	15b
 	isync

 	/* Did we actually switch to the guest at all? */
 	lbz	r6, VCORE_IN_GUEST(r5)
 	cmpwi	r6, 0
 	beq	19f

 	/* Primary thread switches back to host partition */
 	lwz	r7,KVM_HOST_LPID(r4)
 BEGIN_FTR_SECTION
 	ld	r6,KVM_HOST_SDR1(r4)
 	li	r8,LPID_RSVD		/* switch to reserved LPID */
 	mtspr	SPRN_LPID,r8
 	ptesync
 	mtspr	SPRN_SDR1,r6		/* switch to host page table */
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	mtspr	SPRN_LPID,r7
 	isync

 BEGIN_FTR_SECTION
 	/* DPDES and VTB are shared between threads */
 	mfspr	r7, SPRN_DPDES
 	mfspr	r8, SPRN_VTB
 	std	r7, VCORE_DPDES(r5)
 	std	r8, VCORE_VTB(r5)
 	/* clear DPDES so we don't get guest doorbells in the host */
 	li	r8, 0
 	mtspr	SPRN_DPDES, r8
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)

 	/* If HMI, call kvmppc_realmode_hmi_handler() */
 	lwz	r12, STACK_SLOT_TRAP(r1)
 	cmpwi	r12, BOOK3S_INTERRUPT_HMI
 	bne	27f
 	bl	kvmppc_realmode_hmi_handler
 	nop
 	cmpdi	r3, 0
 	/*
 	 * At this point kvmppc_realmode_hmi_handler may have resync-ed
 	 * the TB, and if it has, we must not subtract the guest timebase
 	 * offset from the timebase. So, skip it.
 	 *
 	 * Also, do not call kvmppc_subcore_exit_guest() because it has
 	 * been invoked as part of kvmppc_realmode_hmi_handler().
 	 */
 	beq	30f

 27:
 	/* Subtract timebase offset from timebase */
 	ld	r8, VCORE_TB_OFFSET_APPL(r5)
 	cmpdi	r8,0
 	beq	17f
 	li	r0, 0
 	std	r0, VCORE_TB_OFFSET_APPL(r5)
 	mftb	r6			/* current guest timebase */
 	subf	r8,r8,r6
 	mtspr	SPRN_TBU40,r8		/* update upper 40 bits */
 	mftb	r7			/* check if lower 24 bits overflowed */
 	clrldi	r6,r6,40
 	clrldi	r7,r7,40
 	cmpld	r7,r6
 	bge	17f
 	addis	r8,r8,0x100		/* if so, increment upper 40 bits */
 	mtspr	SPRN_TBU40,r8

 17:	bl	kvmppc_subcore_exit_guest
 	nop
 30:	ld	r5,HSTATE_KVM_VCORE(r13)
 	ld	r4,VCORE_KVM(r5)	/* pointer to struct kvm */

 	/* Reset PCR */
 	ld	r0, VCORE_PCR(r5)
 	cmpdi	r0, 0
 	beq	18f
 	li	r0, 0
 	mtspr	SPRN_PCR, r0
 18:
 	/* Signal secondary CPUs to continue */
 	stb	r0,VCORE_IN_GUEST(r5)
 19:	lis	r8,0x7fff		/* MAX_INT@h */
 	mtspr	SPRN_HDEC,r8

 16:
 BEGIN_FTR_SECTION
 	/* On POWER9 with HPT-on-radix we need to wait for all other threads */
 	ld	r3, HSTATE_SPLIT_MODE(r13)
 	cmpdi	r3, 0
 	beq	47f
 	lwz	r8, KVM_SPLIT_DO_RESTORE(r3)
 	cmpwi	r8, 0
 	beq	47f
 	bl	kvmhv_p9_restore_lpcr
 	nop
 	b	48f
 47:
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	ld	r8,KVM_HOST_LPCR(r4)
 	mtspr	SPRN_LPCR,r8
 	isync
 48:
 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	/* Finish timing, if we have a vcpu */
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	cmpdi	r4, 0
 	li	r3, 0
 	beq	2f
 	bl	kvmhv_accumulate_time
 2:
 #endif
 	/* Unset guest mode */
 	li	r0, KVM_GUEST_MODE_NONE
 	stb	r0, HSTATE_IN_GUEST(r13)

 	lwz	r12, STACK_SLOT_TRAP(r1)	/* return trap # in r12 */
 	ld	r0, SFS+PPC_LR_STKOFF(r1)
 	addi	r1, r1, SFS
 	mtlr	r0
 	blr

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Softpatch interrupt for transactional memory emulation cases
  * on POWER9 DD2.2.  This is early in the guest exit path - we
  * haven't saved registers or done a treclaim yet.
  */
 kvmppc_tm_emul:
 	/* Save instruction image in HEIR */
 	mfspr	r3, SPRN_HEIR
 	stw	r3, VCPU_HEIR(r9)

 	/*
 	 * The cases we want to handle here are those where the guest
 	 * is in real suspend mode and is trying to transition to
 	 * transactional mode.
 	 */
 	lbz	r0, HSTATE_FAKE_SUSPEND(r13)
 	cmpwi	r0, 0		/* keep exiting guest if in fake suspend */
 	bne	guest_exit_cont
 	rldicl	r3, r11, 64 - MSR_TS_S_LG, 62
 	cmpwi	r3, 1		/* or if not in suspend state */
 	bne	guest_exit_cont

 	/* Call C code to do the emulation */
 	mr	r3, r9
 	bl	kvmhv_p9_tm_emulation_early
 	nop
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	li	r12, BOOK3S_INTERRUPT_HV_SOFTPATCH
 	cmpwi	r3, 0
 	beq	guest_exit_cont		/* continue exiting if not handled */
 	ld	r10, VCPU_PC(r9)
 	ld	r11, VCPU_MSR(r9)
 	b	fast_interrupt_c_return	/* go back to guest if handled */
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */

 /*
  * Check whether an HDSI is an HPTE not found fault or something else.
  * If it is an HPTE not found fault that is due to the guest accessing
  * a page that they have mapped but which we have paged out, then
  * we continue on with the guest exit path.  In all other cases,
  * reflect the HDSI to the guest as a DSI.
  */
 kvmppc_hdsi:
 	ld	r3, VCPU_KVM(r9)
 	lbz	r0, KVM_RADIX(r3)
 	mfspr	r4, SPRN_HDAR
 	mfspr	r6, SPRN_HDSISR
 BEGIN_FTR_SECTION
 	/* Look for DSISR canary. If we find it, retry instruction */
 	cmpdi	r6, 0x7fff
 	beq	6f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	cmpwi	r0, 0
 	bne	.Lradix_hdsi		/* on radix, just save DAR/DSISR/ASDR */
 	/* HPTE not found fault or protection fault? */
 	andis.	r0, r6, (DSISR_NOHPTE | DSISR_PROTFAULT)@h
 	beq	1f			/* if not, send it to the guest */
 	andi.	r0, r11, MSR_DR		/* data relocation enabled? */
 	beq	3f
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_ASDR		/* on POWER9, use ASDR to get VSID */
 	b	4f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	clrrdi	r0, r4, 28
 	PPC_SLBFEE_DOT(R5, R0)		/* if so, look up SLB */
 	li	r0, BOOK3S_INTERRUPT_DATA_SEGMENT
 	bne	7f			/* if no SLB entry found */
 4:	std	r4, VCPU_FAULT_DAR(r9)
 	stw	r6, VCPU_FAULT_DSISR(r9)

 	/* Search the hash table. */
 	mr	r3, r9			/* vcpu pointer */
 	li	r7, 1			/* data fault */
 	bl	kvmppc_hpte_hv_fault
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	ld	r10, VCPU_PC(r9)
 	ld	r11, VCPU_MSR(r9)
 	li	r12, BOOK3S_INTERRUPT_H_DATA_STORAGE
 	cmpdi	r3, 0			/* retry the instruction */
 	beq	6f
 	cmpdi	r3, -1			/* handle in kernel mode */
 	beq	guest_exit_cont
 	cmpdi	r3, -2			/* MMIO emulation; need instr word */
 	beq	2f

 	/* Synthesize a DSI (or DSegI) for the guest */
 	ld	r4, VCPU_FAULT_DAR(r9)
 	mr	r6, r3
 1:	li	r0, BOOK3S_INTERRUPT_DATA_STORAGE
 	mtspr	SPRN_DSISR, r6
 7:	mtspr	SPRN_DAR, r4
 	mtspr	SPRN_SRR0, r10
 	mtspr	SPRN_SRR1, r11
 	mr	r10, r0
 	bl	kvmppc_msr_interrupt
 fast_interrupt_c_return:
 6:	ld	r7, VCPU_CTR(r9)
 	ld	r8, VCPU_XER(r9)
 	mtctr	r7
 	mtxer	r8
 	mr	r4, r9
 	b	fast_guest_return

 3:	ld	r5, VCPU_KVM(r9)	/* not relocated, use VRMA */
 	ld	r5, KVM_VRMA_SLB_V(r5)
 	b	4b

 	/* If this is for emulated MMIO, load the instruction word */
 2:	li	r8, KVM_INST_FETCH_FAILED	/* In case lwz faults */

 	/* Set guest mode to 'jump over instruction' so if lwz faults
 	 * we'll just continue at the next IP. */
 	li	r0, KVM_GUEST_MODE_SKIP
 	stb	r0, HSTATE_IN_GUEST(r13)

 	/* Do the access with MSR:DR enabled */
 	mfmsr	r3
 	ori	r4, r3, MSR_DR		/* Enable paging for data */
 	mtmsrd	r4
 	lwz	r8, 0(r10)
 	mtmsrd	r3

 	/* Store the result */
 	stw	r8, VCPU_LAST_INST(r9)

 	/* Unset guest mode. */
 	li	r0, KVM_GUEST_MODE_HOST_HV
 	stb	r0, HSTATE_IN_GUEST(r13)
 	b	guest_exit_cont

 .Lradix_hdsi:
 	std	r4, VCPU_FAULT_DAR(r9)
 	stw	r6, VCPU_FAULT_DSISR(r9)
 .Lradix_hisi:
 	mfspr	r5, SPRN_ASDR
 	std	r5, VCPU_FAULT_GPA(r9)
 	b	guest_exit_cont

 /*
  * Similarly for an HISI, reflect it to the guest as an ISI unless
  * it is an HPTE not found fault for a page that we have paged out.
  */
 kvmppc_hisi:
 	ld	r3, VCPU_KVM(r9)
 	lbz	r0, KVM_RADIX(r3)
 	cmpwi	r0, 0
 	bne	.Lradix_hisi		/* for radix, just save ASDR */
 	andis.	r0, r11, SRR1_ISI_NOPT@h
 	beq	1f
 	andi.	r0, r11, MSR_IR		/* instruction relocation enabled? */
 	beq	3f
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_ASDR		/* on POWER9, use ASDR to get VSID */
 	b	4f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	clrrdi	r0, r10, 28
 	PPC_SLBFEE_DOT(R5, R0)		/* if so, look up SLB */
 	li	r0, BOOK3S_INTERRUPT_INST_SEGMENT
 	bne	7f			/* if no SLB entry found */
 4:
 	/* Search the hash table. */
 	mr	r3, r9			/* vcpu pointer */
 	mr	r4, r10
 	mr	r6, r11
 	li	r7, 0			/* instruction fault */
 	bl	kvmppc_hpte_hv_fault
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	ld	r10, VCPU_PC(r9)
 	ld	r11, VCPU_MSR(r9)
 	li	r12, BOOK3S_INTERRUPT_H_INST_STORAGE
 	cmpdi	r3, 0			/* retry the instruction */
 	beq	fast_interrupt_c_return
 	cmpdi	r3, -1			/* handle in kernel mode */
 	beq	guest_exit_cont

 	/* Synthesize an ISI (or ISegI) for the guest */
 	mr	r11, r3
 1:	li	r0, BOOK3S_INTERRUPT_INST_STORAGE
 7:	mtspr	SPRN_SRR0, r10
 	mtspr	SPRN_SRR1, r11
 	mr	r10, r0
 	bl	kvmppc_msr_interrupt
 	b	fast_interrupt_c_return

 3:	ld	r6, VCPU_KVM(r9)	/* not relocated, use VRMA */
 	ld	r5, KVM_VRMA_SLB_V(r6)
 	b	4b

 /*
  * Try to handle an hcall in real mode.
  * Returns to the guest if we handle it, or continues on up to
  * the kernel if we can't (i.e. if we don't have a handler for
  * it, or if the handler returns H_TOO_HARD).
  *
  * r5 - r8 contain hcall args,
  * r9 = vcpu, r10 = pc, r11 = msr, r12 = trap, r13 = paca
  */
 hcall_try_real_mode:
 	ld	r3,VCPU_GPR(R3)(r9)
 	andi.	r0,r11,MSR_PR
 	/* sc 1 from userspace - reflect to guest syscall */
 	bne	sc_1_fast_return
 	clrrdi	r3,r3,2
 	cmpldi	r3,hcall_real_table_end - hcall_real_table
 	bge	guest_exit_cont
 	/* See if this hcall is enabled for in-kernel handling */
 	ld	r4, VCPU_KVM(r9)
 	srdi	r0, r3, 8	/* r0 = (r3 / 4) >> 6 */
 	sldi	r0, r0, 3	/* index into kvm->arch.enabled_hcalls[] */
 	add	r4, r4, r0
 	ld	r0, KVM_ENABLED_HCALLS(r4)
 	rlwinm	r4, r3, 32-2, 0x3f	/* r4 = (r3 / 4) & 0x3f */
 	srd	r0, r0, r4
 	andi.	r0, r0, 1
 	beq	guest_exit_cont
 	/* Get pointer to handler, if any, and call it */
 	LOAD_REG_ADDR(r4, hcall_real_table)
 	lwax	r3,r3,r4
 	cmpwi	r3,0
 	beq	guest_exit_cont
 	add	r12,r3,r4
 	mtctr	r12
 	mr	r3,r9		/* get vcpu pointer */
 	ld	r4,VCPU_GPR(R4)(r9)
 	bctrl
 	cmpdi	r3,H_TOO_HARD
 	beq	hcall_real_fallback
 	ld	r4,HSTATE_KVM_VCPU(r13)
 	std	r3,VCPU_GPR(R3)(r4)
 	ld	r10,VCPU_PC(r4)
 	ld	r11,VCPU_MSR(r4)
 	b	fast_guest_return

 sc_1_fast_return:
 	mtspr	SPRN_SRR0,r10
 	mtspr	SPRN_SRR1,r11
 	li	r10, BOOK3S_INTERRUPT_SYSCALL
 	bl	kvmppc_msr_interrupt
 	mr	r4,r9
 	b	fast_guest_return

 	/* We've attempted a real mode hcall, but it's punted it back
 	 * to userspace.  We need to restore some clobbered volatiles
 	 * before resuming the pass-it-to-qemu path */
 hcall_real_fallback:
 	li	r12,BOOK3S_INTERRUPT_SYSCALL
 	ld	r9, HSTATE_KVM_VCPU(r13)

 	b	guest_exit_cont

 	.globl	hcall_real_table
 hcall_real_table:
 	.long	0		/* 0 - unused */
 	.long	DOTSYM(kvmppc_h_remove) - hcall_real_table
 	.long	DOTSYM(kvmppc_h_enter) - hcall_real_table
 	.long	DOTSYM(kvmppc_h_read) - hcall_real_table
 	.long	DOTSYM(kvmppc_h_clear_mod) - hcall_real_table
 	.long	DOTSYM(kvmppc_h_clear_ref) - hcall_real_table
 	.long	DOTSYM(kvmppc_h_protect) - hcall_real_table
 	.long	DOTSYM(kvmppc_h_get_tce) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_put_tce) - hcall_real_table
 	.long	0		/* 0x24 - H_SET_SPRG0 */
 	.long	DOTSYM(kvmppc_h_set_dabr) - hcall_real_table
 	.long	0		/* 0x2c */
 	.long	0		/* 0x30 */
 	.long	0		/* 0x34 */
 	.long	0		/* 0x38 */
 	.long	0		/* 0x3c */
 	.long	0		/* 0x40 */
 	.long	0		/* 0x44 */
 	.long	0		/* 0x48 */
 	.long	0		/* 0x4c */
 	.long	0		/* 0x50 */
 	.long	0		/* 0x54 */
 	.long	0		/* 0x58 */
 	.long	0		/* 0x5c */
 	.long	0		/* 0x60 */
 #ifdef CONFIG_KVM_XICS
 	.long	DOTSYM(kvmppc_rm_h_eoi) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_cppr) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_ipi) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_ipoll) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_xirr) - hcall_real_table
 #else
 	.long	0		/* 0x64 - H_EOI */
 	.long	0		/* 0x68 - H_CPPR */
 	.long	0		/* 0x6c - H_IPI */
 	.long	0		/* 0x70 - H_IPOLL */
 	.long	0		/* 0x74 - H_XIRR */
 #endif
 	.long	0		/* 0x78 */
 	.long	0		/* 0x7c */
 	.long	0		/* 0x80 */
 	.long	0		/* 0x84 */
 	.long	0		/* 0x88 */
 	.long	0		/* 0x8c */
 	.long	0		/* 0x90 */
 	.long	0		/* 0x94 */
 	.long	0		/* 0x98 */
 	.long	0		/* 0x9c */
 	.long	0		/* 0xa0 */
 	.long	0		/* 0xa4 */
 	.long	0		/* 0xa8 */
 	.long	0		/* 0xac */
 	.long	0		/* 0xb0 */
 	.long	0		/* 0xb4 */
 	.long	0		/* 0xb8 */
 	.long	0		/* 0xbc */
 	.long	0		/* 0xc0 */
 	.long	0		/* 0xc4 */
 	.long	0		/* 0xc8 */
 	.long	0		/* 0xcc */
 	.long	0		/* 0xd0 */
 	.long	0		/* 0xd4 */
 	.long	0		/* 0xd8 */
 	.long	0		/* 0xdc */
 	.long	DOTSYM(kvmppc_h_cede) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_confer) - hcall_real_table
 	.long	0		/* 0xe8 */
 	.long	0		/* 0xec */
 	.long	0		/* 0xf0 */
 	.long	0		/* 0xf4 */
 	.long	0		/* 0xf8 */
 	.long	0		/* 0xfc */
 	.long	0		/* 0x100 */
 	.long	0		/* 0x104 */
 	.long	0		/* 0x108 */
 	.long	0		/* 0x10c */
 	.long	0		/* 0x110 */
 	.long	0		/* 0x114 */
 	.long	0		/* 0x118 */
 	.long	0		/* 0x11c */
 	.long	0		/* 0x120 */
 	.long	DOTSYM(kvmppc_h_bulk_remove) - hcall_real_table
 	.long	0		/* 0x128 */
 	.long	0		/* 0x12c */
 	.long	0		/* 0x130 */
 	.long	DOTSYM(kvmppc_h_set_xdabr) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_stuff_tce) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_put_tce_indirect) - hcall_real_table
 	.long	0		/* 0x140 */
 	.long	0		/* 0x144 */
 	.long	0		/* 0x148 */
 	.long	0		/* 0x14c */
 	.long	0		/* 0x150 */
 	.long	0		/* 0x154 */
 	.long	0		/* 0x158 */
 	.long	0		/* 0x15c */
 	.long	0		/* 0x160 */
 	.long	0		/* 0x164 */
 	.long	0		/* 0x168 */
 	.long	0		/* 0x16c */
 	.long	0		/* 0x170 */
 	.long	0		/* 0x174 */
 	.long	0		/* 0x178 */
 	.long	0		/* 0x17c */
 	.long	0		/* 0x180 */
 	.long	0		/* 0x184 */
 	.long	0		/* 0x188 */
 	.long	0		/* 0x18c */
 	.long	0		/* 0x190 */
 	.long	0		/* 0x194 */
 	.long	0		/* 0x198 */
 	.long	0		/* 0x19c */
 	.long	0		/* 0x1a0 */
 	.long	0		/* 0x1a4 */
 	.long	0		/* 0x1a8 */
 	.long	0		/* 0x1ac */
 	.long	0		/* 0x1b0 */
 	.long	0		/* 0x1b4 */
 	.long	0		/* 0x1b8 */
 	.long	0		/* 0x1bc */
 	.long	0		/* 0x1c0 */
 	.long	0		/* 0x1c4 */
 	.long	0		/* 0x1c8 */
 	.long	0		/* 0x1cc */
 	.long	0		/* 0x1d0 */
 	.long	0		/* 0x1d4 */
 	.long	0		/* 0x1d8 */
 	.long	0		/* 0x1dc */
 	.long	0		/* 0x1e0 */
 	.long	0		/* 0x1e4 */
 	.long	0		/* 0x1e8 */
 	.long	0		/* 0x1ec */
 	.long	0		/* 0x1f0 */
 	.long	0		/* 0x1f4 */
 	.long	0		/* 0x1f8 */
 	.long	0		/* 0x1fc */
 	.long	0		/* 0x200 */
 	.long	0		/* 0x204 */
 	.long	0		/* 0x208 */
 	.long	0		/* 0x20c */
 	.long	0		/* 0x210 */
 	.long	0		/* 0x214 */
 	.long	0		/* 0x218 */
 	.long	0		/* 0x21c */
 	.long	0		/* 0x220 */
 	.long	0		/* 0x224 */
 	.long	0		/* 0x228 */
 	.long	0		/* 0x22c */
 	.long	0		/* 0x230 */
 	.long	0		/* 0x234 */
 	.long	0		/* 0x238 */
 	.long	0		/* 0x23c */
 	.long	0		/* 0x240 */
 	.long	0		/* 0x244 */
 	.long	0		/* 0x248 */
 	.long	0		/* 0x24c */
 	.long	0		/* 0x250 */
 	.long	0		/* 0x254 */
 	.long	0		/* 0x258 */
 	.long	0		/* 0x25c */
 	.long	0		/* 0x260 */
 	.long	0		/* 0x264 */
 	.long	0		/* 0x268 */
 	.long	0		/* 0x26c */
 	.long	0		/* 0x270 */
 	.long	0		/* 0x274 */
 	.long	0		/* 0x278 */
 	.long	0		/* 0x27c */
 	.long	0		/* 0x280 */
 	.long	0		/* 0x284 */
 	.long	0		/* 0x288 */
 	.long	0		/* 0x28c */
 	.long	0		/* 0x290 */
 	.long	0		/* 0x294 */
 	.long	0		/* 0x298 */
 	.long	0		/* 0x29c */
 	.long	0		/* 0x2a0 */
 	.long	0		/* 0x2a4 */
 	.long	0		/* 0x2a8 */
 	.long	0		/* 0x2ac */
 	.long	0		/* 0x2b0 */
 	.long	0		/* 0x2b4 */
 	.long	0		/* 0x2b8 */
 	.long	0		/* 0x2bc */
 	.long	0		/* 0x2c0 */
 	.long	0		/* 0x2c4 */
 	.long	0		/* 0x2c8 */
 	.long	0		/* 0x2cc */
 	.long	0		/* 0x2d0 */
 	.long	0		/* 0x2d4 */
 	.long	0		/* 0x2d8 */
 	.long	0		/* 0x2dc */
 	.long	0		/* 0x2e0 */
 	.long	0		/* 0x2e4 */
 	.long	0		/* 0x2e8 */
 	.long	0		/* 0x2ec */
 	.long	0		/* 0x2f0 */
 	.long	0		/* 0x2f4 */
 	.long	0		/* 0x2f8 */
 #ifdef CONFIG_KVM_XICS
 	.long	DOTSYM(kvmppc_rm_h_xirr_x) - hcall_real_table
 #else
 	.long	0		/* 0x2fc - H_XIRR_X*/
 #endif
 	.long	DOTSYM(kvmppc_h_random) - hcall_real_table
 	.globl	hcall_real_table_end
 hcall_real_table_end:

 _GLOBAL(kvmppc_h_set_xdabr)
 	andi.	r0, r5, DABRX_USER | DABRX_KERNEL
 	beq	6f
 	li	r0, DABRX_USER | DABRX_KERNEL | DABRX_BTI
 	andc.	r0, r5, r0
 	beq	3f
 6:	li	r3, H_PARAMETER
 	blr

 _GLOBAL(kvmppc_h_set_dabr)
 	li	r5, DABRX_USER | DABRX_KERNEL
 3:
 BEGIN_FTR_SECTION
 	b	2f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	std	r4,VCPU_DABR(r3)
 	stw	r5, VCPU_DABRX(r3)
 	mtspr	SPRN_DABRX, r5
 	/* Work around P7 bug where DABR can get corrupted on mtspr */
 1:	mtspr	SPRN_DABR,r4
 	mfspr	r5, SPRN_DABR
 	cmpd	r4, r5
 	bne	1b
 	isync
 	li	r3,0
 	blr

 2:
 BEGIN_FTR_SECTION
 	/* POWER9 with disabled DAWR */
 	li	r3, H_HARDWARE
 	blr
 END_FTR_SECTION_IFCLR(CPU_FTR_DAWR)
 	/* Emulate H_SET_DABR/X on P8 for the sake of compat mode guests */
 	rlwimi	r5, r4, 5, DAWRX_DR | DAWRX_DW
 	rlwimi	r5, r4, 2, DAWRX_WT
 	clrrdi	r4, r4, 3
 	std	r4, VCPU_DAWR(r3)
 	std	r5, VCPU_DAWRX(r3)
 	mtspr	SPRN_DAWR, r4
 	mtspr	SPRN_DAWRX, r5
 	li	r3, 0
 	blr

 _GLOBAL(kvmppc_h_cede)		/* r3 = vcpu pointer, r11 = msr, r13 = paca */
 	ori	r11,r11,MSR_EE
 	std	r11,VCPU_MSR(r3)
 	li	r0,1
 	stb	r0,VCPU_CEDED(r3)
 	sync			/* order setting ceded vs. testing prodded */
 	lbz	r5,VCPU_PRODDED(r3)
 	cmpwi	r5,0
 	bne	kvm_cede_prodded
 	li	r12,0		/* set trap to 0 to say hcall is handled */
 	stw	r12,VCPU_TRAP(r3)
 	li	r0,H_SUCCESS
 	std	r0,VCPU_GPR(R3)(r3)

 	/*
 	 * Set our bit in the bitmask of napping threads unless all the
 	 * other threads are already napping, in which case we send this
 	 * up to the host.
 	 */
 	ld	r5,HSTATE_KVM_VCORE(r13)
 	lbz	r6,HSTATE_PTID(r13)
 	lwz	r8,VCORE_ENTRY_EXIT(r5)
 	clrldi	r8,r8,56
 	li	r0,1
 	sld	r0,r0,r6
 	addi	r6,r5,VCORE_NAPPING_THREADS
 31:	lwarx	r4,0,r6
 	or	r4,r4,r0
 	cmpw	r4,r8
 	beq	kvm_cede_exit
 	stwcx.	r4,0,r6
 	bne	31b
 	/* order napping_threads update vs testing entry_exit_map */
 	isync
 	li	r0,NAPPING_CEDE
 	stb	r0,HSTATE_NAPPING(r13)
 	lwz	r7,VCORE_ENTRY_EXIT(r5)
 	cmpwi	r7,0x100
 	bge	33f		/* another thread already exiting */

 /*
  * Although not specifically required by the architecture, POWER7
  * preserves the following registers in nap mode, even if an SMT mode
  * switch occurs: SLB entries, PURR, SPURR, AMOR, UAMOR, AMR, SPRG0-3,
  * DAR, DSISR, DABR, DABRX, DSCR, PMCx, MMCRx, SIAR, SDAR.
  */
 	/* Save non-volatile GPRs */
 	std	r14, VCPU_GPR(R14)(r3)
 	std	r15, VCPU_GPR(R15)(r3)
 	std	r16, VCPU_GPR(R16)(r3)
 	std	r17, VCPU_GPR(R17)(r3)
 	std	r18, VCPU_GPR(R18)(r3)
 	std	r19, VCPU_GPR(R19)(r3)
 	std	r20, VCPU_GPR(R20)(r3)
 	std	r21, VCPU_GPR(R21)(r3)
 	std	r22, VCPU_GPR(R22)(r3)
 	std	r23, VCPU_GPR(R23)(r3)
 	std	r24, VCPU_GPR(R24)(r3)
 	std	r25, VCPU_GPR(R25)(r3)
 	std	r26, VCPU_GPR(R26)(r3)
 	std	r27, VCPU_GPR(R27)(r3)
 	std	r28, VCPU_GPR(R28)(r3)
 	std	r29, VCPU_GPR(R29)(r3)
 	std	r30, VCPU_GPR(R30)(r3)
 	std	r31, VCPU_GPR(R31)(r3)

 	/* save FP state */
 	bl	kvmppc_save_fp

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Branch around the call if both CPU_FTR_TM and
  * CPU_FTR_P9_TM_HV_ASSIST are off.
  */
 BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
 	 */
 	ld	r3, HSTATE_KVM_VCPU(r13)
 	ld      r4, VCPU_MSR(r3)
 	bl	kvmppc_save_tm_hv
 91:
 #endif

 	/*
 	 * Set DEC to the smaller of DEC and HDEC, so that we wake
 	 * no later than the end of our timeslice (HDEC interrupts
 	 * don't wake us from nap).
 	 */
 	mfspr	r3, SPRN_DEC
 	mfspr	r4, SPRN_HDEC
 	mftb	r5
 BEGIN_FTR_SECTION
 	/* On P9 check whether the guest has large decrementer mode enabled */
 	ld	r6, HSTATE_KVM_VCORE(r13)
 	ld	r6, VCORE_LPCR(r6)
 	andis.	r6, r6, LPCR_LD@h
 	bne	68f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r3, r3
 68:	EXTEND_HDEC(r4)
 	cmpd	r3, r4
 	ble	67f
 	mtspr	SPRN_DEC, r4
 67:
 	/* save expiry time of guest decrementer */
 	add	r3, r3, r5
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r6, VCORE_TB_OFFSET_APPL(r5)
 	subf	r3, r6, r3	/* convert to host TB value */
 	std	r3, VCPU_DEC_EXPIRES(r4)

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	ld	r4, HSTATE_KVM_VCPU(r13)
 	addi	r3, r4, VCPU_TB_CEDE
 	bl	kvmhv_accumulate_time
 #endif

 	lis	r3, LPCR_PECEDP@h	/* Do wake on privileged doorbell */

 	/*
 	 * Take a nap until a decrementer or external or doobell interrupt
 	 * occurs, with PECE1 and PECE0 set in LPCR.
 	 * On POWER8, set PECEDH, and if we are ceding, also set PECEDP.
 	 * Also clear the runlatch bit before napping.
 	 */
 kvm_do_nap:
 	mfspr	r0, SPRN_CTRLF
 	clrrdi	r0, r0, 1
 	mtspr	SPRN_CTRLT, r0

 	li	r0,1
 	stb	r0,HSTATE_HWTHREAD_REQ(r13)
 	mfspr	r5,SPRN_LPCR
 	ori	r5,r5,LPCR_PECE0 | LPCR_PECE1
 BEGIN_FTR_SECTION
 	ori	r5, r5, LPCR_PECEDH
 	rlwimi	r5, r3, 0, LPCR_PECEDP
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)

 kvm_nap_sequence:		/* desired LPCR value in r5 */
 BEGIN_FTR_SECTION
 	/*
 	 * PSSCR bits:	exit criterion = 1 (wakeup based on LPCR at sreset)
 	 *		enable state loss = 1 (allow SMT mode switch)
 	 *		requested level = 0 (just stop dispatching)
 	 */
 	lis	r3, (PSSCR_EC | PSSCR_ESL)@h
 	mtspr	SPRN_PSSCR, r3
 	/* Set LPCR_PECE_HVEE bit to enable wakeup by HV interrupts */
 	li	r4, LPCR_PECE_HVEE@higher
 	sldi	r4, r4, 32
 	or	r5, r5, r4
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	mtspr	SPRN_LPCR,r5
 	isync
 	li	r0, 0
 	std	r0, HSTATE_SCRATCH0(r13)
 	ptesync
 	ld	r0, HSTATE_SCRATCH0(r13)
 1:	cmpd	r0, r0
 	bne	1b
 BEGIN_FTR_SECTION
 	nap
 FTR_SECTION_ELSE
 	PPC_STOP
 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	b	.

 33:	mr	r4, r3
 	li	r3, 0
 	li	r12, 0
 	b	34f

 kvm_end_cede:
 	/* get vcpu pointer */
 	ld	r4, HSTATE_KVM_VCPU(r13)

 	/* Woken by external or decrementer interrupt */
 	ld	r1, HSTATE_HOST_R1(r13)

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r4, VCPU_TB_RMINTR
 	bl	kvmhv_accumulate_time
 #endif

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Branch around the call if both CPU_FTR_TM and
  * CPU_FTR_P9_TM_HV_ASSIST are off.
  */
 BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
 	 */
 	mr      r3, r4
 	ld      r4, VCPU_MSR(r3)
 	bl	kvmppc_restore_tm_hv
 	ld	r4, HSTATE_KVM_VCPU(r13)
 91:
 #endif

 	/* load up FP state */
 	bl	kvmppc_load_fp

 	/* Restore guest decrementer */
 	ld	r3, VCPU_DEC_EXPIRES(r4)
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r6, VCORE_TB_OFFSET_APPL(r5)
 	add	r3, r3, r6	/* convert host TB to guest TB value */
 	mftb	r7
 	subf	r3, r7, r3
 	mtspr	SPRN_DEC, r3

 	/* Load NV GPRS */
 	ld	r14, VCPU_GPR(R14)(r4)
 	ld	r15, VCPU_GPR(R15)(r4)
 	ld	r16, VCPU_GPR(R16)(r4)
 	ld	r17, VCPU_GPR(R17)(r4)
 	ld	r18, VCPU_GPR(R18)(r4)
 	ld	r19, VCPU_GPR(R19)(r4)
 	ld	r20, VCPU_GPR(R20)(r4)
 	ld	r21, VCPU_GPR(R21)(r4)
 	ld	r22, VCPU_GPR(R22)(r4)
 	ld	r23, VCPU_GPR(R23)(r4)
 	ld	r24, VCPU_GPR(R24)(r4)
 	ld	r25, VCPU_GPR(R25)(r4)
 	ld	r26, VCPU_GPR(R26)(r4)
 	ld	r27, VCPU_GPR(R27)(r4)
 	ld	r28, VCPU_GPR(R28)(r4)
 	ld	r29, VCPU_GPR(R29)(r4)
 	ld	r30, VCPU_GPR(R30)(r4)
 	ld	r31, VCPU_GPR(R31)(r4)

 	/* Check the wake reason in SRR1 to see why we got here */
 	bl	kvmppc_check_wake_reason

 	/*
 	 * Restore volatile registers since we could have called a
 	 * C routine in kvmppc_check_wake_reason
 	 *	r4 = VCPU
 	 * r3 tells us whether we need to return to host or not
 	 * WARNING: it gets checked further down:
 	 * should not modify r3 until this check is done.
 	 */
 	ld	r4, HSTATE_KVM_VCPU(r13)

 	/* clear our bit in vcore->napping_threads */
 34:	ld	r5,HSTATE_KVM_VCORE(r13)
 	lbz	r7,HSTATE_PTID(r13)
 	li	r0,1
 	sld	r0,r0,r7
 	addi	r6,r5,VCORE_NAPPING_THREADS
 32:	lwarx	r7,0,r6
 	andc	r7,r7,r0
 	stwcx.	r7,0,r6
 	bne	32b
 	li	r0,0
 	stb	r0,HSTATE_NAPPING(r13)

 	/* See if the wake reason saved in r3 means we need to exit */
 	stw	r12, VCPU_TRAP(r4)
 	mr	r9, r4
 	cmpdi	r3, 0
 	bgt	guest_exit_cont

 	/* see if any other thread is already exiting */
 	lwz	r0,VCORE_ENTRY_EXIT(r5)
 	cmpwi	r0,0x100
 	bge	guest_exit_cont

 	b	kvmppc_cede_reentry	/* if not go back to guest */

 	/* cede when already previously prodded case */
 kvm_cede_prodded:
 	li	r0,0
 	stb	r0,VCPU_PRODDED(r3)
 	sync			/* order testing prodded vs. clearing ceded */
 	stb	r0,VCPU_CEDED(r3)
 	li	r3,H_SUCCESS
 	blr

 	/* we've ceded but we want to give control to the host */
 kvm_cede_exit:
 	ld	r9, HSTATE_KVM_VCPU(r13)
 #ifdef CONFIG_KVM_XICS
 	/* Abort if we still have a pending escalation */
 	lbz	r5, VCPU_XIVE_ESC_ON(r9)
 	cmpwi	r5, 0
 	beq	1f
 	li	r0, 0
 	stb	r0, VCPU_CEDED(r9)
 1:	/* Enable XIVE escalation */
 	li	r5, XIVE_ESB_SET_PQ_00
 	mfmsr	r0
 	andi.	r0, r0, MSR_DR		/* in real mode? */
 	beq	1f
 	ld	r10, VCPU_XIVE_ESC_VADDR(r9)
 	cmpdi	r10, 0
 	beq	3f
 	ldx	r0, r10, r5
 	b	2f
 1:	ld	r10, VCPU_XIVE_ESC_RADDR(r9)
 	cmpdi	r10, 0
 	beq	3f
 	ldcix	r0, r10, r5
 2:	sync
 	li	r0, 1
 	stb	r0, VCPU_XIVE_ESC_ON(r9)
 #endif /* CONFIG_KVM_XICS */
 3:	b	guest_exit_cont

 	/* Try to handle a machine check in real mode */
 machine_check_realmode:
 	mr	r3, r9		/* get vcpu pointer */
 	bl	kvmppc_realmode_machine_check
 	nop
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	li	r12, BOOK3S_INTERRUPT_MACHINE_CHECK
 	/*
 	 * For the guest that is FWNMI capable, deliver all the MCE errors
 	 * (handled/unhandled) by exiting the guest with KVM_EXIT_NMI exit
 	 * reason. This new approach injects machine check errors in guest
 	 * address space to guest with additional information in the form
 	 * of RTAS event, thus enabling guest kernel to suitably handle
 	 * such errors.
 	 *
 	 * For the guest that is not FWNMI capable (old QEMU) fallback
 	 * to old behaviour for backward compatibility:
 	 * Deliver unhandled/fatal (e.g. UE) MCE errors to guest either
 	 * through machine check interrupt (set HSRR0 to 0x200).
 	 * For handled errors (no-fatal), just go back to guest execution
 	 * with current HSRR0.
 	 * if we receive machine check with MSR(RI=0) then deliver it to
 	 * guest as machine check causing guest to crash.
 	 */
 	ld	r11, VCPU_MSR(r9)
 	rldicl.	r0, r11, 64-MSR_HV_LG, 63 /* check if it happened in HV mode */
 	bne	mc_cont			/* if so, exit to host */
 	/* Check if guest is capable of handling NMI exit */
 	ld	r10, VCPU_KVM(r9)
 	lbz	r10, KVM_FWNMI(r10)
 	cmpdi	r10, 1			/* FWNMI capable? */
 	beq	mc_cont			/* if so, exit with KVM_EXIT_NMI. */

 	/* if not, fall through for backward compatibility. */
 	andi.	r10, r11, MSR_RI	/* check for unrecoverable exception */
 	beq	1f			/* Deliver a machine check to guest */
 	ld	r10, VCPU_PC(r9)
 	cmpdi	r3, 0		/* Did we handle MCE ? */
 	bne	2f	/* Continue guest execution. */
 	/* If not, deliver a machine check.  SRR0/1 are already set */
 1:	li	r10, BOOK3S_INTERRUPT_MACHINE_CHECK
 	bl	kvmppc_msr_interrupt
 2:	b	fast_interrupt_c_return

 /*
  * Check the reason we woke from nap, and take appropriate action.
  * Returns (in r3):
  *	0 if nothing needs to be done
  *	1 if something happened that needs to be handled by the host
  *	-1 if there was a guest wakeup (IPI or msgsnd)
  *	-2 if we handled a PCI passthrough interrupt (returned by
  *		kvmppc_read_intr only)
  *
  * Also sets r12 to the interrupt vector for any interrupt that needs
  * to be handled now by the host (0x500 for external interrupt), or zero.
  * Modifies all volatile registers (since it may call a C function).
  * This routine calls kvmppc_read_intr, a C function, if an external
  * interrupt is pending.
  */
 kvmppc_check_wake_reason:
 	mfspr	r6, SPRN_SRR1
 BEGIN_FTR_SECTION
 	rlwinm	r6, r6, 45-31, 0xf	/* extract wake reason field (P8) */
 FTR_SECTION_ELSE
 	rlwinm	r6, r6, 45-31, 0xe	/* P7 wake reason field is 3 bits */
 ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_207S)
 	cmpwi	r6, 8			/* was it an external interrupt? */
 	beq	7f			/* if so, see what it was */
 	li	r3, 0
 	li	r12, 0
 	cmpwi	r6, 6			/* was it the decrementer? */
 	beq	0f
 BEGIN_FTR_SECTION
 	cmpwi	r6, 5			/* privileged doorbell? */
 	beq	0f
 	cmpwi	r6, 3			/* hypervisor doorbell? */
 	beq	3f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	cmpwi	r6, 0xa			/* Hypervisor maintenance ? */
 	beq	4f
 	li	r3, 1			/* anything else, return 1 */
 0:	blr

 	/* hypervisor doorbell */
 3:	li	r12, BOOK3S_INTERRUPT_H_DOORBELL

 	/*
 	 * Clear the doorbell as we will invoke the handler
 	 * explicitly in the guest exit path.
 	 */
 	lis	r6, (PPC_DBELL_SERVER << (63-36))@h
 	PPC_MSGCLR(6)
 	/* see if it's a host IPI */
 	li	r3, 1
 BEGIN_FTR_SECTION
 	PPC_MSGSYNC
 	lwsync
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	lbz	r0, HSTATE_HOST_IPI(r13)
 	cmpwi	r0, 0
 	bnelr
 	/* if not, return -1 */
 	li	r3, -1
 	blr

 	/* Woken up due to Hypervisor maintenance interrupt */
 4:	li	r12, BOOK3S_INTERRUPT_HMI
 	li	r3, 1
 	blr

 	/* external interrupt - create a stack frame so we can call C */
 7:	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
 	stdu	r1, -PPC_MIN_STKFRM(r1)
 	bl	kvmppc_read_intr
 	nop
 	li	r12, BOOK3S_INTERRUPT_EXTERNAL
 	cmpdi	r3, 1
 	ble	1f

 	/*
 	 * Return code of 2 means PCI passthrough interrupt, but
 	 * we need to return back to host to complete handling the
 	 * interrupt. Trap reason is expected in r12 by guest
 	 * exit code.
 	 */
 	li	r12, BOOK3S_INTERRUPT_HV_RM_HARD
 1:
 	ld	r0, PPC_MIN_STKFRM+PPC_LR_STKOFF(r1)
 	addi	r1, r1, PPC_MIN_STKFRM
 	mtlr	r0
 	blr

 /*
  * Save away FP, VMX and VSX registers.
  * r3 = vcpu pointer
  * N.B. r30 and r31 are volatile across this function,
  * thus it is not callable from C.
  */
 kvmppc_save_fp:
 	mflr	r30
 	mr	r31,r3
 	mfmsr	r5
 	ori	r8,r5,MSR_FP
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	oris	r8,r8,MSR_VEC@h
 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 #endif
 #ifdef CONFIG_VSX
 BEGIN_FTR_SECTION
 	oris	r8,r8,MSR_VSX@h
 END_FTR_SECTION_IFSET(CPU_FTR_VSX)
 #endif
 	mtmsrd	r8
 	addi	r3,r3,VCPU_FPRS
 	bl	store_fp_state
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	addi	r3,r31,VCPU_VRS
 	bl	store_vr_state
 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 #endif
 	mfspr	r6,SPRN_VRSAVE
 	stw	r6,VCPU_VRSAVE(r31)
 	mtlr	r30
 	blr

 /*
  * Load up FP, VMX and VSX registers
  * r4 = vcpu pointer
  * N.B. r30 and r31 are volatile across this function,
  * thus it is not callable from C.
  */
 kvmppc_load_fp:
 	mflr	r30
 	mr	r31,r4
 	mfmsr	r9
 	ori	r8,r9,MSR_FP
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	oris	r8,r8,MSR_VEC@h
 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 #endif
 #ifdef CONFIG_VSX
 BEGIN_FTR_SECTION
 	oris	r8,r8,MSR_VSX@h
 END_FTR_SECTION_IFSET(CPU_FTR_VSX)
 #endif
 	mtmsrd	r8
 	addi	r3,r4,VCPU_FPRS
 	bl	load_fp_state
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	addi	r3,r31,VCPU_VRS
 	bl	load_vr_state
 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 #endif
 	lwz	r7,VCPU_VRSAVE(r31)
 	mtspr	SPRN_VRSAVE,r7
 	mtlr	r30
 	mr	r4,r31
 	blr

 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Save transactional state and TM-related registers.
  * Called with r3 pointing to the vcpu struct and r4 containing
  * the guest MSR value.
  * This can modify all checkpointed registers, but
  * restores r1 and r2 before exit.
  */
 kvmppc_save_tm_hv:
 	/* See if we need to handle fake suspend mode */
 BEGIN_FTR_SECTION
 	b	__kvmppc_save_tm
 END_FTR_SECTION_IFCLR(CPU_FTR_P9_TM_HV_ASSIST)

 	lbz	r0, HSTATE_FAKE_SUSPEND(r13) /* Were we fake suspended? */
 	cmpwi	r0, 0
 	beq	__kvmppc_save_tm

 	/* The following code handles the fake_suspend = 1 case */
 	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
 	stdu	r1, -PPC_MIN_STKFRM(r1)

 	/* Turn on TM. */
 	mfmsr	r8
 	li	r0, 1
 	rldimi	r8, r0, MSR_TM_LG, 63-MSR_TM_LG
 	mtmsrd	r8

 	rldicl. r8, r8, 64 - MSR_TS_S_LG, 62 /* Did we actually hrfid? */
 	beq	4f
 BEGIN_FTR_SECTION
 	bl	pnv_power9_force_smt4_catch
 END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG)
 	nop

 	std	r1, HSTATE_HOST_R1(r13)

 	/* Clear the MSR RI since r1, r13 may be foobar. */
 	li	r5, 0
 	mtmsrd	r5, 1

 	/* We have to treclaim here because that's the only way to do S->N */
 	li	r3, TM_CAUSE_KVM_RESCHED
 	TRECLAIM(R3)

 	/*
 	 * We were in fake suspend, so we are not going to save the
 	 * register state as the guest checkpointed state (since
 	 * we already have it), therefore we can now use any volatile GPR.
 	 */
 	/* Reload PACA pointer, stack pointer and TOC. */
 	GET_PACA(r13)
 	ld	r1, HSTATE_HOST_R1(r13)
 	ld	r2, PACATOC(r13)

 	/* Set MSR RI now we have r1 and r13 back. */
 	li	r5, MSR_RI
 	mtmsrd	r5, 1

 	HMT_MEDIUM
 	ld	r6, HSTATE_DSCR(r13)
 	mtspr	SPRN_DSCR, r6
 BEGIN_FTR_SECTION_NESTED(96)
 	bl	pnv_power9_force_smt4_release
 END_FTR_SECTION_NESTED(CPU_FTR_P9_TM_XER_SO_BUG, CPU_FTR_P9_TM_XER_SO_BUG, 96)
 	nop

 4:
 	mfspr	r3, SPRN_PSSCR
 	/* PSSCR_FAKE_SUSPEND is a write-only bit, but clear it anyway */
 	li	r0, PSSCR_FAKE_SUSPEND
 	andc	r3, r3, r0
 	mtspr	SPRN_PSSCR, r3

 	/* Don't save TEXASR, use value from last exit in real suspend state */
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	mfspr	r5, SPRN_TFHAR
 	mfspr	r6, SPRN_TFIAR
 	std	r5, VCPU_TFHAR(r9)
 	std	r6, VCPU_TFIAR(r9)

 	addi	r1, r1, PPC_MIN_STKFRM
 	ld	r0, PPC_LR_STKOFF(r1)
 	mtlr	r0
 	blr

 /*
  * Restore transactional state and TM-related registers.
  * Called with r3 pointing to the vcpu struct
  * and r4 containing the guest MSR value.
  * This potentially modifies all checkpointed registers.
  * It restores r1 and r2 from the PACA.
  */
 kvmppc_restore_tm_hv:
 	/*
 	 * If we are doing TM emulation for the guest on a POWER9 DD2,
 	 * then we don't actually do a trechkpt -- we either set up
 	 * fake-suspend mode, or emulate a TM rollback.
 	 */
 BEGIN_FTR_SECTION
 	b	__kvmppc_restore_tm
 END_FTR_SECTION_IFCLR(CPU_FTR_P9_TM_HV_ASSIST)
 	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)

 	li	r0, 0
 	stb	r0, HSTATE_FAKE_SUSPEND(r13)

 	/* Turn on TM so we can restore TM SPRs */
 	mfmsr	r5
 	li	r0, 1
 	rldimi	r5, r0, MSR_TM_LG, 63-MSR_TM_LG
 	mtmsrd	r5

 	/*
 	 * The user may change these outside of a transaction, so they must
 	 * always be context switched.
 	 */
 	ld	r5, VCPU_TFHAR(r3)
 	ld	r6, VCPU_TFIAR(r3)
 	ld	r7, VCPU_TEXASR(r3)
 	mtspr	SPRN_TFHAR, r5
 	mtspr	SPRN_TFIAR, r6
 	mtspr	SPRN_TEXASR, r7

 	rldicl. r5, r4, 64 - MSR_TS_S_LG, 62
 	beqlr		/* TM not active in guest */

 	/* Make sure the failure summary is set */
 	oris	r7, r7, (TEXASR_FS)@h
 	mtspr	SPRN_TEXASR, r7

 	cmpwi	r5, 1		/* check for suspended state */
 	bgt	10f
 	stb	r5, HSTATE_FAKE_SUSPEND(r13)
 	b	9f		/* and return */
 10:	stdu	r1, -PPC_MIN_STKFRM(r1)
 	/* guest is in transactional state, so simulate rollback */
 	bl	kvmhv_emulate_tm_rollback
 	nop
 	addi	r1, r1, PPC_MIN_STKFRM
 9:	ld	r0, PPC_LR_STKOFF(r1)
 	mtlr	r0
 	blr
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */

 /*
  * We come here if we get any exception or interrupt while we are
  * executing host real mode code while in guest MMU context.
  * r12 is (CR << 32) | vector
  * r13 points to our PACA
  * r12 is saved in HSTATE_SCRATCH0(r13)
  * ctr is saved in HSTATE_SCRATCH1(r13) if RELOCATABLE
  * r9 is saved in HSTATE_SCRATCH2(r13)
  * r13 is saved in HSPRG1
  * cfar is saved in HSTATE_CFAR(r13)
  * ppr is saved in HSTATE_PPR(r13)
  */
 kvmppc_bad_host_intr:
 	/*
 	 * Switch to the emergency stack, but start half-way down in
 	 * case we were already on it.
 	 */
 	mr	r9, r1
 	std	r1, PACAR1(r13)
 	ld	r1, PACAEMERGSP(r13)
 	subi	r1, r1, THREAD_SIZE/2 + INT_FRAME_SIZE
 	std	r9, 0(r1)
 	std	r0, GPR0(r1)
 	std	r9, GPR1(r1)
 	std	r2, GPR2(r1)
 	SAVE_4GPRS(3, r1)
 	SAVE_2GPRS(7, r1)
 	srdi	r0, r12, 32
 	clrldi	r12, r12, 32
 	std	r0, _CCR(r1)
 	std	r12, _TRAP(r1)
 	andi.	r0, r12, 2
 	beq	1f
 	mfspr	r3, SPRN_HSRR0
 	mfspr	r4, SPRN_HSRR1
 	mfspr	r5, SPRN_HDAR
 	mfspr	r6, SPRN_HDSISR
 	b	2f
 1:	mfspr	r3, SPRN_SRR0
 	mfspr	r4, SPRN_SRR1
 	mfspr	r5, SPRN_DAR
 	mfspr	r6, SPRN_DSISR
 2:	std	r3, _NIP(r1)
 	std	r4, _MSR(r1)
 	std	r5, _DAR(r1)
 	std	r6, _DSISR(r1)
 	ld	r9, HSTATE_SCRATCH2(r13)
 	ld	r12, HSTATE_SCRATCH0(r13)
 	GET_SCRATCH0(r0)
 	SAVE_4GPRS(9, r1)
 	std	r0, GPR13(r1)
 	SAVE_NVGPRS(r1)
 	ld	r5, HSTATE_CFAR(r13)
 	std	r5, ORIG_GPR3(r1)
 	mflr	r3
 #ifdef CONFIG_RELOCATABLE
 	ld	r4, HSTATE_SCRATCH1(r13)
 #else
 	mfctr	r4
 #endif
 	mfxer	r5
 	lbz	r6, PACAIRQSOFTMASK(r13)
 	std	r3, _LINK(r1)
 	std	r4, _CTR(r1)
 	std	r5, _XER(r1)
 	std	r6, SOFTE(r1)
 	ld	r2, PACATOC(r13)
 	LOAD_REG_IMMEDIATE(3, 0x7265677368657265)
 	std	r3, STACK_FRAME_OVERHEAD-16(r1)

 	/*
 	 * On POWER9 do a minimal restore of the MMU and call C code,
 	 * which will print a message and panic.
 	 * XXX On POWER7 and POWER8, we just spin here since we don't
 	 * know what the other threads are doing (and we don't want to
 	 * coordinate with them) - but at least we now have register state
 	 * in memory that we might be able to look at from another CPU.
 	 */
 BEGIN_FTR_SECTION
 	b	.
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	ld	r10, VCPU_KVM(r9)

 	li	r0, 0
 	mtspr	SPRN_AMR, r0
 	mtspr	SPRN_IAMR, r0
 	mtspr	SPRN_CIABR, r0
 	mtspr	SPRN_DAWRX, r0

 BEGIN_MMU_FTR_SECTION
 	b	4f
 END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)

 	slbmte	r0, r0
 	slbia
 	ptesync
 	ld	r8, PACA_SLBSHADOWPTR(r13)
 	.rept	SLB_NUM_BOLTED
 	li	r3, SLBSHADOW_SAVEAREA
 	LDX_BE	r5, r8, r3
 	addi	r3, r3, 8
 	LDX_BE	r6, r8, r3
 	andis.	r7, r5, SLB_ESID_V@h
 	beq	3f
 	slbmte	r6, r5
 3:	addi	r8, r8, 16
 	.endr

 4:	lwz	r7, KVM_HOST_LPID(r10)
 	mtspr	SPRN_LPID, r7
 	mtspr	SPRN_PID, r0
 	ld	r8, KVM_HOST_LPCR(r10)
 	mtspr	SPRN_LPCR, r8
 	isync
 	li	r0, KVM_GUEST_MODE_NONE
 	stb	r0, HSTATE_IN_GUEST(r13)

 	/*
 	 * Turn on the MMU and jump to C code
 	 */
 	bcl	20, 31, .+4
 5:	mflr	r3
 	addi	r3, r3, 9f - 5b
 	li	r4, -1
 	rldimi	r3, r4, 62, 0	/* ensure 0xc000000000000000 bits are set */
 	ld	r4, PACAKMSR(r13)
 	mtspr	SPRN_SRR0, r3
 	mtspr	SPRN_SRR1, r4
 	RFI_TO_KERNEL
 9:	addi	r3, r1, STACK_FRAME_OVERHEAD
 	bl	kvmppc_bad_interrupt
 	b	9b

 /*
  * This mimics the MSR transition on IRQ delivery.  The new guest MSR is taken
  * from VCPU_INTR_MSR and is modified based on the required TM state changes.
  *   r11 has the guest MSR value (in/out)
  *   r9 has a vcpu pointer (in)
  *   r0 is used as a scratch register
  */
 kvmppc_msr_interrupt:
 	rldicl	r0, r11, 64 - MSR_TS_S_LG, 62
 	cmpwi	r0, 2 /* Check if we are in transactional state..  */
 	ld	r11, VCPU_INTR_MSR(r9)
 	bne	1f
 	/* ... if transactional, change to suspended */
 	li	r0, 1
 1:	rldimi	r11, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
 	blr

 /*
  * This works around a hardware bug on POWER8E processors, where
  * writing a 1 to the MMCR0[PMAO] bit doesn't generate a
  * performance monitor interrupt.  Instead, when we need to have
  * an interrupt pending, we have to arrange for a counter to overflow.
  */
 kvmppc_fix_pmao:
 	li	r3, 0
 	mtspr	SPRN_MMCR2, r3
 	lis	r3, (MMCR0_PMXE | MMCR0_FCECE)@h
 	ori	r3, r3, MMCR0_PMCjCE | MMCR0_C56RUN
 	mtspr	SPRN_MMCR0, r3
 	lis	r3, 0x7fff
 	ori	r3, r3, 0xffff
 	mtspr	SPRN_PMC6, r3
 	isync
 	blr

 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 /*
  * Start timing an activity
  * r3 = pointer to time accumulation struct, r4 = vcpu
  */
 kvmhv_start_timing:
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r6, VCORE_TB_OFFSET_APPL(r5)
 	mftb	r5
 	subf	r5, r6, r5	/* subtract current timebase offset */
 	std	r3, VCPU_CUR_ACTIVITY(r4)
 	std	r5, VCPU_ACTIVITY_START(r4)
 	blr

 /*
  * Accumulate time to one activity and start another.
  * r3 = pointer to new time accumulation struct, r4 = vcpu
  */
 kvmhv_accumulate_time:
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r8, VCORE_TB_OFFSET_APPL(r5)
 	ld	r5, VCPU_CUR_ACTIVITY(r4)
 	ld	r6, VCPU_ACTIVITY_START(r4)
 	std	r3, VCPU_CUR_ACTIVITY(r4)
 	mftb	r7
 	subf	r7, r8, r7	/* subtract current timebase offset */
 	std	r7, VCPU_ACTIVITY_START(r4)
 	cmpdi	r5, 0
 	beqlr
 	subf	r3, r6, r7
 	ld	r8, TAS_SEQCOUNT(r5)
 	cmpdi	r8, 0
 	addi	r8, r8, 1
 	std	r8, TAS_SEQCOUNT(r5)
 	lwsync
 	ld	r7, TAS_TOTAL(r5)
 	add	r7, r7, r3
 	std	r7, TAS_TOTAL(r5)
 	ld	r6, TAS_MIN(r5)
 	ld	r7, TAS_MAX(r5)
 	beq	3f
 	cmpd	r3, r6
 	bge	1f
 3:	std	r3, TAS_MIN(r5)
 1:	cmpd	r3, r7
 	ble	2f
 	std	r3, TAS_MAX(r5)
 2:	lwsync
 	addi	r8, r8, 1
 	std	r8, TAS_SEQCOUNT(r5)
 	blr
 #endif