xref: /openbmc/qemu/target/i386/hvf/hvf.c (revision 1580b897)
1 /* Copyright 2008 IBM Corporation
2  *           2008 Red Hat, Inc.
3  * Copyright 2011 Intel Corporation
4  * Copyright 2016 Veertu, Inc.
5  * Copyright 2017 The Android Open Source Project
6  *
7  * QEMU Hypervisor.framework support
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of version 2 of the GNU General Public
11  * License as published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, see <http://www.gnu.org/licenses/>.
20  *
21  * This file contain code under public domain from the hvdos project:
22  * https://github.com/mist64/hvdos
23  *
24  * Parts Copyright (c) 2011 NetApp, Inc.
25  * All rights reserved.
26  *
27  * Redistribution and use in source and binary forms, with or without
28  * modification, are permitted provided that the following conditions
29  * are met:
30  * 1. Redistributions of source code must retain the above copyright
31  *    notice, this list of conditions and the following disclaimer.
32  * 2. Redistributions in binary form must reproduce the above copyright
33  *    notice, this list of conditions and the following disclaimer in the
34  *    documentation and/or other materials provided with the distribution.
35  *
36  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46  * SUCH DAMAGE.
47  */
48 
49 #include "qemu/osdep.h"
50 #include "qemu-common.h"
51 #include "qemu/error-report.h"
52 
53 #include "sysemu/hvf.h"
54 #include "sysemu/hvf_int.h"
55 #include "sysemu/runstate.h"
56 #include "hvf-i386.h"
57 #include "vmcs.h"
58 #include "vmx.h"
59 #include "x86.h"
60 #include "x86_descr.h"
61 #include "x86_mmu.h"
62 #include "x86_decode.h"
63 #include "x86_emu.h"
64 #include "x86_task.h"
65 #include "x86hvf.h"
66 
67 #include <Hypervisor/hv.h>
68 #include <Hypervisor/hv_vmx.h>
69 #include <sys/sysctl.h>
70 
71 #include "hw/i386/apic_internal.h"
72 #include "qemu/main-loop.h"
73 #include "qemu/accel.h"
74 #include "target/i386/cpu.h"
75 
76 void vmx_update_tpr(CPUState *cpu)
77 {
78     /* TODO: need integrate APIC handling */
79     X86CPU *x86_cpu = X86_CPU(cpu);
80     int tpr = cpu_get_apic_tpr(x86_cpu->apic_state) << 4;
81     int irr = apic_get_highest_priority_irr(x86_cpu->apic_state);
82 
83     wreg(cpu->hvf->fd, HV_X86_TPR, tpr);
84     if (irr == -1) {
85         wvmcs(cpu->hvf->fd, VMCS_TPR_THRESHOLD, 0);
86     } else {
87         wvmcs(cpu->hvf->fd, VMCS_TPR_THRESHOLD, (irr > tpr) ? tpr >> 4 :
88               irr >> 4);
89     }
90 }
91 
92 static void update_apic_tpr(CPUState *cpu)
93 {
94     X86CPU *x86_cpu = X86_CPU(cpu);
95     int tpr = rreg(cpu->hvf->fd, HV_X86_TPR) >> 4;
96     cpu_set_apic_tpr(x86_cpu->apic_state, tpr);
97 }
98 
99 #define VECTORING_INFO_VECTOR_MASK     0xff
100 
101 void hvf_handle_io(CPUArchState *env, uint16_t port, void *buffer,
102                   int direction, int size, int count)
103 {
104     int i;
105     uint8_t *ptr = buffer;
106 
107     for (i = 0; i < count; i++) {
108         address_space_rw(&address_space_io, port, MEMTXATTRS_UNSPECIFIED,
109                          ptr, size,
110                          direction);
111         ptr += size;
112     }
113 }
114 
115 static bool ept_emulation_fault(hvf_slot *slot, uint64_t gpa, uint64_t ept_qual)
116 {
117     int read, write;
118 
119     /* EPT fault on an instruction fetch doesn't make sense here */
120     if (ept_qual & EPT_VIOLATION_INST_FETCH) {
121         return false;
122     }
123 
124     /* EPT fault must be a read fault or a write fault */
125     read = ept_qual & EPT_VIOLATION_DATA_READ ? 1 : 0;
126     write = ept_qual & EPT_VIOLATION_DATA_WRITE ? 1 : 0;
127     if ((read | write) == 0) {
128         return false;
129     }
130 
131     if (write && slot) {
132         if (slot->flags & HVF_SLOT_LOG) {
133             memory_region_set_dirty(slot->region, gpa - slot->start, 1);
134             hv_vm_protect((hv_gpaddr_t)slot->start, (size_t)slot->size,
135                           HV_MEMORY_READ | HV_MEMORY_WRITE);
136         }
137     }
138 
139     /*
140      * The EPT violation must have been caused by accessing a
141      * guest-physical address that is a translation of a guest-linear
142      * address.
143      */
144     if ((ept_qual & EPT_VIOLATION_GLA_VALID) == 0 ||
145         (ept_qual & EPT_VIOLATION_XLAT_VALID) == 0) {
146         return false;
147     }
148 
149     if (!slot) {
150         return true;
151     }
152     if (!memory_region_is_ram(slot->region) &&
153         !(read && memory_region_is_romd(slot->region))) {
154         return true;
155     }
156     return false;
157 }
158 
159 void hvf_arch_vcpu_destroy(CPUState *cpu)
160 {
161     X86CPU *x86_cpu = X86_CPU(cpu);
162     CPUX86State *env = &x86_cpu->env;
163 
164     g_free(env->hvf_mmio_buf);
165 }
166 
167 static void init_tsc_freq(CPUX86State *env)
168 {
169     size_t length;
170     uint64_t tsc_freq;
171 
172     if (env->tsc_khz != 0) {
173         return;
174     }
175 
176     length = sizeof(uint64_t);
177     if (sysctlbyname("machdep.tsc.frequency", &tsc_freq, &length, NULL, 0)) {
178         return;
179     }
180     env->tsc_khz = tsc_freq / 1000;  /* Hz to KHz */
181 }
182 
183 static void init_apic_bus_freq(CPUX86State *env)
184 {
185     size_t length;
186     uint64_t bus_freq;
187 
188     if (env->apic_bus_freq != 0) {
189         return;
190     }
191 
192     length = sizeof(uint64_t);
193     if (sysctlbyname("hw.busfrequency", &bus_freq, &length, NULL, 0)) {
194         return;
195     }
196     env->apic_bus_freq = bus_freq;
197 }
198 
199 static inline bool tsc_is_known(CPUX86State *env)
200 {
201     return env->tsc_khz != 0;
202 }
203 
204 static inline bool apic_bus_freq_is_known(CPUX86State *env)
205 {
206     return env->apic_bus_freq != 0;
207 }
208 
209 int hvf_arch_init_vcpu(CPUState *cpu)
210 {
211     X86CPU *x86cpu = X86_CPU(cpu);
212     CPUX86State *env = &x86cpu->env;
213 
214     init_emu();
215     init_decoder();
216 
217     hvf_state->hvf_caps = g_new0(struct hvf_vcpu_caps, 1);
218     env->hvf_mmio_buf = g_new(char, 4096);
219 
220     if (x86cpu->vmware_cpuid_freq) {
221         init_tsc_freq(env);
222         init_apic_bus_freq(env);
223 
224         if (!tsc_is_known(env) || !apic_bus_freq_is_known(env)) {
225             error_report("vmware-cpuid-freq: feature couldn't be enabled");
226         }
227     }
228 
229     if (hv_vmx_read_capability(HV_VMX_CAP_PINBASED,
230         &hvf_state->hvf_caps->vmx_cap_pinbased)) {
231         abort();
232     }
233     if (hv_vmx_read_capability(HV_VMX_CAP_PROCBASED,
234         &hvf_state->hvf_caps->vmx_cap_procbased)) {
235         abort();
236     }
237     if (hv_vmx_read_capability(HV_VMX_CAP_PROCBASED2,
238         &hvf_state->hvf_caps->vmx_cap_procbased2)) {
239         abort();
240     }
241     if (hv_vmx_read_capability(HV_VMX_CAP_ENTRY,
242         &hvf_state->hvf_caps->vmx_cap_entry)) {
243         abort();
244     }
245 
246     /* set VMCS control fields */
247     wvmcs(cpu->hvf->fd, VMCS_PIN_BASED_CTLS,
248           cap2ctrl(hvf_state->hvf_caps->vmx_cap_pinbased,
249           VMCS_PIN_BASED_CTLS_EXTINT |
250           VMCS_PIN_BASED_CTLS_NMI |
251           VMCS_PIN_BASED_CTLS_VNMI));
252     wvmcs(cpu->hvf->fd, VMCS_PRI_PROC_BASED_CTLS,
253           cap2ctrl(hvf_state->hvf_caps->vmx_cap_procbased,
254           VMCS_PRI_PROC_BASED_CTLS_HLT |
255           VMCS_PRI_PROC_BASED_CTLS_MWAIT |
256           VMCS_PRI_PROC_BASED_CTLS_TSC_OFFSET |
257           VMCS_PRI_PROC_BASED_CTLS_TPR_SHADOW) |
258           VMCS_PRI_PROC_BASED_CTLS_SEC_CONTROL);
259     wvmcs(cpu->hvf->fd, VMCS_SEC_PROC_BASED_CTLS,
260           cap2ctrl(hvf_state->hvf_caps->vmx_cap_procbased2,
261                    VMCS_PRI_PROC_BASED2_CTLS_APIC_ACCESSES));
262 
263     wvmcs(cpu->hvf->fd, VMCS_ENTRY_CTLS, cap2ctrl(hvf_state->hvf_caps->vmx_cap_entry,
264           0));
265     wvmcs(cpu->hvf->fd, VMCS_EXCEPTION_BITMAP, 0); /* Double fault */
266 
267     wvmcs(cpu->hvf->fd, VMCS_TPR_THRESHOLD, 0);
268 
269     x86cpu = X86_CPU(cpu);
270     x86cpu->env.xsave_buf_len = 4096;
271     x86cpu->env.xsave_buf = qemu_memalign(4096, x86cpu->env.xsave_buf_len);
272 
273     /*
274      * The allocated storage must be large enough for all of the
275      * possible XSAVE state components.
276      */
277     assert(hvf_get_supported_cpuid(0xd, 0, R_ECX) <= x86cpu->env.xsave_buf_len);
278 
279     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_STAR, 1);
280     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_LSTAR, 1);
281     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_CSTAR, 1);
282     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_FMASK, 1);
283     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_FSBASE, 1);
284     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_GSBASE, 1);
285     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_KERNELGSBASE, 1);
286     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_TSC_AUX, 1);
287     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_IA32_TSC, 1);
288     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_IA32_SYSENTER_CS, 1);
289     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_IA32_SYSENTER_EIP, 1);
290     hv_vcpu_enable_native_msr(cpu->hvf->fd, MSR_IA32_SYSENTER_ESP, 1);
291 
292     return 0;
293 }
294 
295 static void hvf_store_events(CPUState *cpu, uint32_t ins_len, uint64_t idtvec_info)
296 {
297     X86CPU *x86_cpu = X86_CPU(cpu);
298     CPUX86State *env = &x86_cpu->env;
299 
300     env->exception_nr = -1;
301     env->exception_pending = 0;
302     env->exception_injected = 0;
303     env->interrupt_injected = -1;
304     env->nmi_injected = false;
305     env->ins_len = 0;
306     env->has_error_code = false;
307     if (idtvec_info & VMCS_IDT_VEC_VALID) {
308         switch (idtvec_info & VMCS_IDT_VEC_TYPE) {
309         case VMCS_IDT_VEC_HWINTR:
310         case VMCS_IDT_VEC_SWINTR:
311             env->interrupt_injected = idtvec_info & VMCS_IDT_VEC_VECNUM;
312             break;
313         case VMCS_IDT_VEC_NMI:
314             env->nmi_injected = true;
315             break;
316         case VMCS_IDT_VEC_HWEXCEPTION:
317         case VMCS_IDT_VEC_SWEXCEPTION:
318             env->exception_nr = idtvec_info & VMCS_IDT_VEC_VECNUM;
319             env->exception_injected = 1;
320             break;
321         case VMCS_IDT_VEC_PRIV_SWEXCEPTION:
322         default:
323             abort();
324         }
325         if ((idtvec_info & VMCS_IDT_VEC_TYPE) == VMCS_IDT_VEC_SWEXCEPTION ||
326             (idtvec_info & VMCS_IDT_VEC_TYPE) == VMCS_IDT_VEC_SWINTR) {
327             env->ins_len = ins_len;
328         }
329         if (idtvec_info & VMCS_IDT_VEC_ERRCODE_VALID) {
330             env->has_error_code = true;
331             env->error_code = rvmcs(cpu->hvf->fd, VMCS_IDT_VECTORING_ERROR);
332         }
333     }
334     if ((rvmcs(cpu->hvf->fd, VMCS_GUEST_INTERRUPTIBILITY) &
335         VMCS_INTERRUPTIBILITY_NMI_BLOCKING)) {
336         env->hflags2 |= HF2_NMI_MASK;
337     } else {
338         env->hflags2 &= ~HF2_NMI_MASK;
339     }
340     if (rvmcs(cpu->hvf->fd, VMCS_GUEST_INTERRUPTIBILITY) &
341          (VMCS_INTERRUPTIBILITY_STI_BLOCKING |
342          VMCS_INTERRUPTIBILITY_MOVSS_BLOCKING)) {
343         env->hflags |= HF_INHIBIT_IRQ_MASK;
344     } else {
345         env->hflags &= ~HF_INHIBIT_IRQ_MASK;
346     }
347 }
348 
349 static void hvf_cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
350                               uint32_t *eax, uint32_t *ebx,
351                               uint32_t *ecx, uint32_t *edx)
352 {
353     /*
354      * A wrapper extends cpu_x86_cpuid with 0x40000000 and 0x40000010 leafs,
355      * leafs 0x40000001-0x4000000F are filled with zeros
356      * Provides vmware-cpuid-freq support to hvf
357      *
358      * Note: leaf 0x40000000 not exposes HVF,
359      * leaving hypervisor signature empty
360      */
361 
362     if (index < 0x40000000 || index > 0x40000010 ||
363         !tsc_is_known(env) || !apic_bus_freq_is_known(env)) {
364 
365         cpu_x86_cpuid(env, index, count, eax, ebx, ecx, edx);
366         return;
367     }
368 
369     switch (index) {
370     case 0x40000000:
371         *eax = 0x40000010;    /* Max available cpuid leaf */
372         *ebx = 0;             /* Leave signature empty */
373         *ecx = 0;
374         *edx = 0;
375         break;
376     case 0x40000010:
377         *eax = env->tsc_khz;
378         *ebx = env->apic_bus_freq / 1000; /* Hz to KHz */
379         *ecx = 0;
380         *edx = 0;
381         break;
382     default:
383         *eax = 0;
384         *ebx = 0;
385         *ecx = 0;
386         *edx = 0;
387         break;
388     }
389 }
390 
391 int hvf_vcpu_exec(CPUState *cpu)
392 {
393     X86CPU *x86_cpu = X86_CPU(cpu);
394     CPUX86State *env = &x86_cpu->env;
395     int ret = 0;
396     uint64_t rip = 0;
397 
398     if (hvf_process_events(cpu)) {
399         return EXCP_HLT;
400     }
401 
402     do {
403         if (cpu->vcpu_dirty) {
404             hvf_put_registers(cpu);
405             cpu->vcpu_dirty = false;
406         }
407 
408         if (hvf_inject_interrupts(cpu)) {
409             return EXCP_INTERRUPT;
410         }
411         vmx_update_tpr(cpu);
412 
413         qemu_mutex_unlock_iothread();
414         if (!cpu_is_bsp(X86_CPU(cpu)) && cpu->halted) {
415             qemu_mutex_lock_iothread();
416             return EXCP_HLT;
417         }
418 
419         hv_return_t r  = hv_vcpu_run(cpu->hvf->fd);
420         assert_hvf_ok(r);
421 
422         /* handle VMEXIT */
423         uint64_t exit_reason = rvmcs(cpu->hvf->fd, VMCS_EXIT_REASON);
424         uint64_t exit_qual = rvmcs(cpu->hvf->fd, VMCS_EXIT_QUALIFICATION);
425         uint32_t ins_len = (uint32_t)rvmcs(cpu->hvf->fd,
426                                            VMCS_EXIT_INSTRUCTION_LENGTH);
427 
428         uint64_t idtvec_info = rvmcs(cpu->hvf->fd, VMCS_IDT_VECTORING_INFO);
429 
430         hvf_store_events(cpu, ins_len, idtvec_info);
431         rip = rreg(cpu->hvf->fd, HV_X86_RIP);
432         env->eflags = rreg(cpu->hvf->fd, HV_X86_RFLAGS);
433 
434         qemu_mutex_lock_iothread();
435 
436         update_apic_tpr(cpu);
437         current_cpu = cpu;
438 
439         ret = 0;
440         switch (exit_reason) {
441         case EXIT_REASON_HLT: {
442             macvm_set_rip(cpu, rip + ins_len);
443             if (!((cpu->interrupt_request & CPU_INTERRUPT_HARD) &&
444                 (env->eflags & IF_MASK))
445                 && !(cpu->interrupt_request & CPU_INTERRUPT_NMI) &&
446                 !(idtvec_info & VMCS_IDT_VEC_VALID)) {
447                 cpu->halted = 1;
448                 ret = EXCP_HLT;
449                 break;
450             }
451             ret = EXCP_INTERRUPT;
452             break;
453         }
454         case EXIT_REASON_MWAIT: {
455             ret = EXCP_INTERRUPT;
456             break;
457         }
458         /* Need to check if MMIO or unmapped fault */
459         case EXIT_REASON_EPT_FAULT:
460         {
461             hvf_slot *slot;
462             uint64_t gpa = rvmcs(cpu->hvf->fd, VMCS_GUEST_PHYSICAL_ADDRESS);
463 
464             if (((idtvec_info & VMCS_IDT_VEC_VALID) == 0) &&
465                 ((exit_qual & EXIT_QUAL_NMIUDTI) != 0)) {
466                 vmx_set_nmi_blocking(cpu);
467             }
468 
469             slot = hvf_find_overlap_slot(gpa, 1);
470             /* mmio */
471             if (ept_emulation_fault(slot, gpa, exit_qual)) {
472                 struct x86_decode decode;
473 
474                 load_regs(cpu);
475                 decode_instruction(env, &decode);
476                 exec_instruction(env, &decode);
477                 store_regs(cpu);
478                 break;
479             }
480             break;
481         }
482         case EXIT_REASON_INOUT:
483         {
484             uint32_t in = (exit_qual & 8) != 0;
485             uint32_t size =  (exit_qual & 7) + 1;
486             uint32_t string =  (exit_qual & 16) != 0;
487             uint32_t port =  exit_qual >> 16;
488             /*uint32_t rep = (exit_qual & 0x20) != 0;*/
489 
490             if (!string && in) {
491                 uint64_t val = 0;
492                 load_regs(cpu);
493                 hvf_handle_io(env, port, &val, 0, size, 1);
494                 if (size == 1) {
495                     AL(env) = val;
496                 } else if (size == 2) {
497                     AX(env) = val;
498                 } else if (size == 4) {
499                     RAX(env) = (uint32_t)val;
500                 } else {
501                     RAX(env) = (uint64_t)val;
502                 }
503                 env->eip += ins_len;
504                 store_regs(cpu);
505                 break;
506             } else if (!string && !in) {
507                 RAX(env) = rreg(cpu->hvf->fd, HV_X86_RAX);
508                 hvf_handle_io(env, port, &RAX(env), 1, size, 1);
509                 macvm_set_rip(cpu, rip + ins_len);
510                 break;
511             }
512             struct x86_decode decode;
513 
514             load_regs(cpu);
515             decode_instruction(env, &decode);
516             assert(ins_len == decode.len);
517             exec_instruction(env, &decode);
518             store_regs(cpu);
519 
520             break;
521         }
522         case EXIT_REASON_CPUID: {
523             uint32_t rax = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RAX);
524             uint32_t rbx = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RBX);
525             uint32_t rcx = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RCX);
526             uint32_t rdx = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RDX);
527 
528             if (rax == 1) {
529                 /* CPUID1.ecx.OSXSAVE needs to know CR4 */
530                 env->cr[4] = rvmcs(cpu->hvf->fd, VMCS_GUEST_CR4);
531             }
532             hvf_cpu_x86_cpuid(env, rax, rcx, &rax, &rbx, &rcx, &rdx);
533 
534             wreg(cpu->hvf->fd, HV_X86_RAX, rax);
535             wreg(cpu->hvf->fd, HV_X86_RBX, rbx);
536             wreg(cpu->hvf->fd, HV_X86_RCX, rcx);
537             wreg(cpu->hvf->fd, HV_X86_RDX, rdx);
538 
539             macvm_set_rip(cpu, rip + ins_len);
540             break;
541         }
542         case EXIT_REASON_XSETBV: {
543             X86CPU *x86_cpu = X86_CPU(cpu);
544             CPUX86State *env = &x86_cpu->env;
545             uint32_t eax = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RAX);
546             uint32_t ecx = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RCX);
547             uint32_t edx = (uint32_t)rreg(cpu->hvf->fd, HV_X86_RDX);
548 
549             if (ecx) {
550                 macvm_set_rip(cpu, rip + ins_len);
551                 break;
552             }
553             env->xcr0 = ((uint64_t)edx << 32) | eax;
554             wreg(cpu->hvf->fd, HV_X86_XCR0, env->xcr0 | 1);
555             macvm_set_rip(cpu, rip + ins_len);
556             break;
557         }
558         case EXIT_REASON_INTR_WINDOW:
559             vmx_clear_int_window_exiting(cpu);
560             ret = EXCP_INTERRUPT;
561             break;
562         case EXIT_REASON_NMI_WINDOW:
563             vmx_clear_nmi_window_exiting(cpu);
564             ret = EXCP_INTERRUPT;
565             break;
566         case EXIT_REASON_EXT_INTR:
567             /* force exit and allow io handling */
568             ret = EXCP_INTERRUPT;
569             break;
570         case EXIT_REASON_RDMSR:
571         case EXIT_REASON_WRMSR:
572         {
573             load_regs(cpu);
574             if (exit_reason == EXIT_REASON_RDMSR) {
575                 simulate_rdmsr(cpu);
576             } else {
577                 simulate_wrmsr(cpu);
578             }
579             env->eip += ins_len;
580             store_regs(cpu);
581             break;
582         }
583         case EXIT_REASON_CR_ACCESS: {
584             int cr;
585             int reg;
586 
587             load_regs(cpu);
588             cr = exit_qual & 15;
589             reg = (exit_qual >> 8) & 15;
590 
591             switch (cr) {
592             case 0x0: {
593                 macvm_set_cr0(cpu->hvf->fd, RRX(env, reg));
594                 break;
595             }
596             case 4: {
597                 macvm_set_cr4(cpu->hvf->fd, RRX(env, reg));
598                 break;
599             }
600             case 8: {
601                 X86CPU *x86_cpu = X86_CPU(cpu);
602                 if (exit_qual & 0x10) {
603                     RRX(env, reg) = cpu_get_apic_tpr(x86_cpu->apic_state);
604                 } else {
605                     int tpr = RRX(env, reg);
606                     cpu_set_apic_tpr(x86_cpu->apic_state, tpr);
607                     ret = EXCP_INTERRUPT;
608                 }
609                 break;
610             }
611             default:
612                 error_report("Unrecognized CR %d", cr);
613                 abort();
614             }
615             env->eip += ins_len;
616             store_regs(cpu);
617             break;
618         }
619         case EXIT_REASON_APIC_ACCESS: { /* TODO */
620             struct x86_decode decode;
621 
622             load_regs(cpu);
623             decode_instruction(env, &decode);
624             exec_instruction(env, &decode);
625             store_regs(cpu);
626             break;
627         }
628         case EXIT_REASON_TPR: {
629             ret = 1;
630             break;
631         }
632         case EXIT_REASON_TASK_SWITCH: {
633             uint64_t vinfo = rvmcs(cpu->hvf->fd, VMCS_IDT_VECTORING_INFO);
634             x68_segment_selector sel = {.sel = exit_qual & 0xffff};
635             vmx_handle_task_switch(cpu, sel, (exit_qual >> 30) & 0x3,
636              vinfo & VMCS_INTR_VALID, vinfo & VECTORING_INFO_VECTOR_MASK, vinfo
637              & VMCS_INTR_T_MASK);
638             break;
639         }
640         case EXIT_REASON_TRIPLE_FAULT: {
641             qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
642             ret = EXCP_INTERRUPT;
643             break;
644         }
645         case EXIT_REASON_RDPMC:
646             wreg(cpu->hvf->fd, HV_X86_RAX, 0);
647             wreg(cpu->hvf->fd, HV_X86_RDX, 0);
648             macvm_set_rip(cpu, rip + ins_len);
649             break;
650         case VMX_REASON_VMCALL:
651             env->exception_nr = EXCP0D_GPF;
652             env->exception_injected = 1;
653             env->has_error_code = true;
654             env->error_code = 0;
655             break;
656         default:
657             error_report("%llx: unhandled exit %llx", rip, exit_reason);
658         }
659     } while (ret == 0);
660 
661     return ret;
662 }
663