linux/arch/powerpc/kvm/emulate_loadstore.c
Paul Mackerras 9b5ab00513 KVM: PPC: Add MMIO emulation for remaining floating-point instructions
For completeness, this adds emulation of the lfiwax and lfiwzx
instructions.  With this, all floating-point load and store instructions
as of Power ISA V2.07 are emulated.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-20 11:37:44 +10:00

663 lines
17 KiB
C

/*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Copyright IBM Corp. 2007
* Copyright 2011 Freescale Semiconductor, Inc.
*
* Authors: Hollis Blanchard <hollisb@us.ibm.com>
*/
#include <linux/jiffies.h>
#include <linux/hrtimer.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm_host.h>
#include <linux/clockchips.h>
#include <asm/reg.h>
#include <asm/time.h>
#include <asm/byteorder.h>
#include <asm/kvm_ppc.h>
#include <asm/disassemble.h>
#include <asm/ppc-opcode.h>
#include "timing.h"
#include "trace.h"
#ifdef CONFIG_PPC_FPU
static bool kvmppc_check_fp_disabled(struct kvm_vcpu *vcpu)
{
if (!(kvmppc_get_msr(vcpu) & MSR_FP)) {
kvmppc_core_queue_fpunavail(vcpu);
return true;
}
return false;
}
#endif /* CONFIG_PPC_FPU */
#ifdef CONFIG_VSX
static bool kvmppc_check_vsx_disabled(struct kvm_vcpu *vcpu)
{
if (!(kvmppc_get_msr(vcpu) & MSR_VSX)) {
kvmppc_core_queue_vsx_unavail(vcpu);
return true;
}
return false;
}
#endif /* CONFIG_VSX */
/*
* XXX to do:
* lfiwax, lfiwzx
* vector loads and stores
*
* Instructions that trap when used on cache-inhibited mappings
* are not emulated here: multiple and string instructions,
* lq/stq, and the load-reserve/store-conditional instructions.
*/
int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
u32 inst;
int ra, rs, rt;
enum emulation_result emulated;
int advance = 1;
/* this default type might be overwritten by subcategories */
kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS);
emulated = kvmppc_get_last_inst(vcpu, INST_GENERIC, &inst);
if (emulated != EMULATE_DONE)
return emulated;
ra = get_ra(inst);
rs = get_rs(inst);
rt = get_rt(inst);
/*
* if mmio_vsx_tx_sx_enabled == 0, copy data between
* VSR[0..31] and memory
* if mmio_vsx_tx_sx_enabled == 1, copy data between
* VSR[32..63] and memory
*/
vcpu->arch.mmio_vsx_tx_sx_enabled = get_tx_or_sx(inst);
vcpu->arch.mmio_vsx_copy_nums = 0;
vcpu->arch.mmio_vsx_offset = 0;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_NONE;
vcpu->arch.mmio_sp64_extend = 0;
vcpu->arch.mmio_sign_extend = 0;
switch (get_op(inst)) {
case 31:
switch (get_xop(inst)) {
case OP_31_XOP_LWZX:
emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
break;
case OP_31_XOP_LWZUX:
emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_LBZX:
emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
break;
case OP_31_XOP_LBZUX:
emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_STDX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 8, 1);
break;
case OP_31_XOP_STDUX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_STWX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 4, 1);
break;
case OP_31_XOP_STWUX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_STBX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 1, 1);
break;
case OP_31_XOP_STBUX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 1, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_LHAX:
emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1);
break;
case OP_31_XOP_LHAUX:
emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_LHZX:
emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
break;
case OP_31_XOP_LHZUX:
emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_STHX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 2, 1);
break;
case OP_31_XOP_STHUX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 2, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_DCBST:
case OP_31_XOP_DCBF:
case OP_31_XOP_DCBI:
/* Do nothing. The guest is performing dcbi because
* hardware DMA is not snooped by the dcache, but
* emulated DMA either goes through the dcache as
* normal writes, or the host kernel has handled dcache
* coherence. */
break;
case OP_31_XOP_LWBRX:
emulated = kvmppc_handle_load(run, vcpu, rt, 4, 0);
break;
case OP_31_XOP_STWBRX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 4, 0);
break;
case OP_31_XOP_LHBRX:
emulated = kvmppc_handle_load(run, vcpu, rt, 2, 0);
break;
case OP_31_XOP_STHBRX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 2, 0);
break;
case OP_31_XOP_LDBRX:
emulated = kvmppc_handle_load(run, vcpu, rt, 8, 0);
break;
case OP_31_XOP_STDBRX:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 8, 0);
break;
case OP_31_XOP_LDX:
emulated = kvmppc_handle_load(run, vcpu, rt, 8, 1);
break;
case OP_31_XOP_LDUX:
emulated = kvmppc_handle_load(run, vcpu, rt, 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_LWAX:
emulated = kvmppc_handle_loads(run, vcpu, rt, 4, 1);
break;
case OP_31_XOP_LWAUX:
emulated = kvmppc_handle_loads(run, vcpu, rt, 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
#ifdef CONFIG_PPC_FPU
case OP_31_XOP_LFSX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 4, 1);
break;
case OP_31_XOP_LFSUX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_LFDX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 8, 1);
break;
case OP_31_XOP_LFDUX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_LFIWAX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_loads(run, vcpu,
KVM_MMIO_REG_FPR|rt, 4, 1);
break;
case OP_31_XOP_LFIWZX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 4, 1);
break;
case OP_31_XOP_STFSX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs), 4, 1);
break;
case OP_31_XOP_STFSUX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs), 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_STFDX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs), 8, 1);
break;
case OP_31_XOP_STFDUX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs), 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_31_XOP_STFIWX:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs), 4, 1);
break;
#endif
#ifdef CONFIG_VSX
case OP_31_XOP_LXSDX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 8, 1, 0);
break;
case OP_31_XOP_LXSSPX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 4, 1, 0);
break;
case OP_31_XOP_LXSIWAX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 4, 1, 1);
break;
case OP_31_XOP_LXSIWZX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 4, 1, 0);
break;
case OP_31_XOP_LXVD2X:
/*
* In this case, the official load/store process is like this:
* Step1, exit from vm by page fault isr, then kvm save vsr.
* Please see guest_exit_cont->store_fp_state->SAVE_32VSRS
* as reference.
*
* Step2, copy data between memory and VCPU
* Notice: for LXVD2X/STXVD2X/LXVW4X/STXVW4X, we use
* 2copies*8bytes or 4copies*4bytes
* to simulate one copy of 16bytes.
* Also there is an endian issue here, we should notice the
* layout of memory.
* Please see MARCO of LXVD2X_ROT/STXVD2X_ROT as more reference.
* If host is little-endian, kvm will call XXSWAPD for
* LXVD2X_ROT/STXVD2X_ROT.
* So, if host is little-endian,
* the postion of memeory should be swapped.
*
* Step3, return to guest, kvm reset register.
* Please see kvmppc_hv_entry->load_fp_state->REST_32VSRS
* as reference.
*/
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 2;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 8, 1, 0);
break;
case OP_31_XOP_LXVW4X:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 4;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_WORD;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 4, 1, 0);
break;
case OP_31_XOP_LXVDSX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type =
KVMPPC_VSX_COPY_DWORD_LOAD_DUMP;
emulated = kvmppc_handle_vsx_load(run, vcpu,
KVM_MMIO_REG_VSX|rt, 8, 1, 0);
break;
case OP_31_XOP_STXSDX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
emulated = kvmppc_handle_vsx_store(run, vcpu,
rs, 8, 1);
break;
case OP_31_XOP_STXSSPX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_vsx_store(run, vcpu,
rs, 4, 1);
break;
case OP_31_XOP_STXSIWX:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_offset = 1;
vcpu->arch.mmio_vsx_copy_nums = 1;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_WORD;
emulated = kvmppc_handle_vsx_store(run, vcpu,
rs, 4, 1);
break;
case OP_31_XOP_STXVD2X:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 2;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_DWORD;
emulated = kvmppc_handle_vsx_store(run, vcpu,
rs, 8, 1);
break;
case OP_31_XOP_STXVW4X:
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_vsx_copy_nums = 4;
vcpu->arch.mmio_vsx_copy_type = KVMPPC_VSX_COPY_WORD;
emulated = kvmppc_handle_vsx_store(run, vcpu,
rs, 4, 1);
break;
#endif /* CONFIG_VSX */
default:
emulated = EMULATE_FAIL;
break;
}
break;
case OP_LWZ:
emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
break;
#ifdef CONFIG_PPC_FPU
case OP_STFS:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs),
4, 1);
break;
case OP_STFSU:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs),
4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_STFD:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs),
8, 1);
break;
case OP_STFDU:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_store(run, vcpu,
VCPU_FPR(vcpu, rs),
8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
#endif
case OP_LD:
rt = get_rt(inst);
switch (inst & 3) {
case 0: /* ld */
emulated = kvmppc_handle_load(run, vcpu, rt, 8, 1);
break;
case 1: /* ldu */
emulated = kvmppc_handle_load(run, vcpu, rt, 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case 2: /* lwa */
emulated = kvmppc_handle_loads(run, vcpu, rt, 4, 1);
break;
default:
emulated = EMULATE_FAIL;
}
break;
case OP_LWZU:
emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_LBZ:
emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
break;
case OP_LBZU:
emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_STW:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs),
4, 1);
break;
case OP_STD:
rs = get_rs(inst);
switch (inst & 3) {
case 0: /* std */
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 8, 1);
break;
case 1: /* stdu */
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
default:
emulated = EMULATE_FAIL;
}
break;
case OP_STWU:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_STB:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 1, 1);
break;
case OP_STBU:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 1, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_LHZ:
emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
break;
case OP_LHZU:
emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_LHA:
emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1);
break;
case OP_LHAU:
emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_STH:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 2, 1);
break;
case OP_STHU:
emulated = kvmppc_handle_store(run, vcpu,
kvmppc_get_gpr(vcpu, rs), 2, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
#ifdef CONFIG_PPC_FPU
case OP_LFS:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 4, 1);
break;
case OP_LFSU:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 4, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
case OP_LFD:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 8, 1);
break;
case OP_LFDU:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
emulated = kvmppc_handle_load(run, vcpu,
KVM_MMIO_REG_FPR|rt, 8, 1);
kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
break;
#endif
default:
emulated = EMULATE_FAIL;
break;
}
if (emulated == EMULATE_FAIL) {
advance = 0;
kvmppc_core_queue_program(vcpu, 0);
}
trace_kvm_ppc_instr(inst, kvmppc_get_pc(vcpu), emulated);
/* Advance past emulated instruction. */
if (advance)
kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) + 4);
return emulated;
}