1 /* SPDX-License-Identifier: GPL-2.0 */
2 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
3
4 #include <linux/kvm_host.h>
5 #include "x86.h"
6 #include "kvm_cache_regs.h"
7 #include "kvm_emulate.h"
8 #include "smm.h"
9 #include "cpuid.h"
10 #include "trace.h"
11
12 #define CHECK_SMRAM32_OFFSET(field, offset) \
13 ASSERT_STRUCT_OFFSET(struct kvm_smram_state_32, field, offset - 0xFE00)
14
15 #define CHECK_SMRAM64_OFFSET(field, offset) \
16 ASSERT_STRUCT_OFFSET(struct kvm_smram_state_64, field, offset - 0xFE00)
17
check_smram_offsets(void)18 static void check_smram_offsets(void)
19 {
20 /* 32 bit SMRAM image */
21 CHECK_SMRAM32_OFFSET(reserved1, 0xFE00);
22 CHECK_SMRAM32_OFFSET(smbase, 0xFEF8);
23 CHECK_SMRAM32_OFFSET(smm_revision, 0xFEFC);
24 CHECK_SMRAM32_OFFSET(io_inst_restart, 0xFF00);
25 CHECK_SMRAM32_OFFSET(auto_hlt_restart, 0xFF02);
26 CHECK_SMRAM32_OFFSET(io_restart_rdi, 0xFF04);
27 CHECK_SMRAM32_OFFSET(io_restart_rcx, 0xFF08);
28 CHECK_SMRAM32_OFFSET(io_restart_rsi, 0xFF0C);
29 CHECK_SMRAM32_OFFSET(io_restart_rip, 0xFF10);
30 CHECK_SMRAM32_OFFSET(cr4, 0xFF14);
31 CHECK_SMRAM32_OFFSET(reserved2, 0xFF18);
32 CHECK_SMRAM32_OFFSET(int_shadow, 0xFF1A);
33 CHECK_SMRAM32_OFFSET(reserved3, 0xFF1B);
34 CHECK_SMRAM32_OFFSET(ds, 0xFF2C);
35 CHECK_SMRAM32_OFFSET(fs, 0xFF38);
36 CHECK_SMRAM32_OFFSET(gs, 0xFF44);
37 CHECK_SMRAM32_OFFSET(idtr, 0xFF50);
38 CHECK_SMRAM32_OFFSET(tr, 0xFF5C);
39 CHECK_SMRAM32_OFFSET(gdtr, 0xFF6C);
40 CHECK_SMRAM32_OFFSET(ldtr, 0xFF78);
41 CHECK_SMRAM32_OFFSET(es, 0xFF84);
42 CHECK_SMRAM32_OFFSET(cs, 0xFF90);
43 CHECK_SMRAM32_OFFSET(ss, 0xFF9C);
44 CHECK_SMRAM32_OFFSET(es_sel, 0xFFA8);
45 CHECK_SMRAM32_OFFSET(cs_sel, 0xFFAC);
46 CHECK_SMRAM32_OFFSET(ss_sel, 0xFFB0);
47 CHECK_SMRAM32_OFFSET(ds_sel, 0xFFB4);
48 CHECK_SMRAM32_OFFSET(fs_sel, 0xFFB8);
49 CHECK_SMRAM32_OFFSET(gs_sel, 0xFFBC);
50 CHECK_SMRAM32_OFFSET(ldtr_sel, 0xFFC0);
51 CHECK_SMRAM32_OFFSET(tr_sel, 0xFFC4);
52 CHECK_SMRAM32_OFFSET(dr7, 0xFFC8);
53 CHECK_SMRAM32_OFFSET(dr6, 0xFFCC);
54 CHECK_SMRAM32_OFFSET(gprs, 0xFFD0);
55 CHECK_SMRAM32_OFFSET(eip, 0xFFF0);
56 CHECK_SMRAM32_OFFSET(eflags, 0xFFF4);
57 CHECK_SMRAM32_OFFSET(cr3, 0xFFF8);
58 CHECK_SMRAM32_OFFSET(cr0, 0xFFFC);
59
60 /* 64 bit SMRAM image */
61 CHECK_SMRAM64_OFFSET(es, 0xFE00);
62 CHECK_SMRAM64_OFFSET(cs, 0xFE10);
63 CHECK_SMRAM64_OFFSET(ss, 0xFE20);
64 CHECK_SMRAM64_OFFSET(ds, 0xFE30);
65 CHECK_SMRAM64_OFFSET(fs, 0xFE40);
66 CHECK_SMRAM64_OFFSET(gs, 0xFE50);
67 CHECK_SMRAM64_OFFSET(gdtr, 0xFE60);
68 CHECK_SMRAM64_OFFSET(ldtr, 0xFE70);
69 CHECK_SMRAM64_OFFSET(idtr, 0xFE80);
70 CHECK_SMRAM64_OFFSET(tr, 0xFE90);
71 CHECK_SMRAM64_OFFSET(io_restart_rip, 0xFEA0);
72 CHECK_SMRAM64_OFFSET(io_restart_rcx, 0xFEA8);
73 CHECK_SMRAM64_OFFSET(io_restart_rsi, 0xFEB0);
74 CHECK_SMRAM64_OFFSET(io_restart_rdi, 0xFEB8);
75 CHECK_SMRAM64_OFFSET(io_restart_dword, 0xFEC0);
76 CHECK_SMRAM64_OFFSET(reserved1, 0xFEC4);
77 CHECK_SMRAM64_OFFSET(io_inst_restart, 0xFEC8);
78 CHECK_SMRAM64_OFFSET(auto_hlt_restart, 0xFEC9);
79 CHECK_SMRAM64_OFFSET(amd_nmi_mask, 0xFECA);
80 CHECK_SMRAM64_OFFSET(int_shadow, 0xFECB);
81 CHECK_SMRAM64_OFFSET(reserved2, 0xFECC);
82 CHECK_SMRAM64_OFFSET(efer, 0xFED0);
83 CHECK_SMRAM64_OFFSET(svm_guest_flag, 0xFED8);
84 CHECK_SMRAM64_OFFSET(svm_guest_vmcb_gpa, 0xFEE0);
85 CHECK_SMRAM64_OFFSET(svm_guest_virtual_int, 0xFEE8);
86 CHECK_SMRAM64_OFFSET(reserved3, 0xFEF0);
87 CHECK_SMRAM64_OFFSET(smm_revison, 0xFEFC);
88 CHECK_SMRAM64_OFFSET(smbase, 0xFF00);
89 CHECK_SMRAM64_OFFSET(reserved4, 0xFF04);
90 CHECK_SMRAM64_OFFSET(ssp, 0xFF18);
91 CHECK_SMRAM64_OFFSET(svm_guest_pat, 0xFF20);
92 CHECK_SMRAM64_OFFSET(svm_host_efer, 0xFF28);
93 CHECK_SMRAM64_OFFSET(svm_host_cr4, 0xFF30);
94 CHECK_SMRAM64_OFFSET(svm_host_cr3, 0xFF38);
95 CHECK_SMRAM64_OFFSET(svm_host_cr0, 0xFF40);
96 CHECK_SMRAM64_OFFSET(cr4, 0xFF48);
97 CHECK_SMRAM64_OFFSET(cr3, 0xFF50);
98 CHECK_SMRAM64_OFFSET(cr0, 0xFF58);
99 CHECK_SMRAM64_OFFSET(dr7, 0xFF60);
100 CHECK_SMRAM64_OFFSET(dr6, 0xFF68);
101 CHECK_SMRAM64_OFFSET(rflags, 0xFF70);
102 CHECK_SMRAM64_OFFSET(rip, 0xFF78);
103 CHECK_SMRAM64_OFFSET(gprs, 0xFF80);
104
105 BUILD_BUG_ON(sizeof(union kvm_smram) != 512);
106 }
107
108 #undef CHECK_SMRAM64_OFFSET
109 #undef CHECK_SMRAM32_OFFSET
110
111
kvm_smm_changed(struct kvm_vcpu * vcpu,bool entering_smm)112 void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm)
113 {
114 trace_kvm_smm_transition(vcpu->vcpu_id, vcpu->arch.smbase, entering_smm);
115
116 if (entering_smm) {
117 vcpu->arch.hflags |= HF_SMM_MASK;
118 } else {
119 vcpu->arch.hflags &= ~(HF_SMM_MASK | HF_SMM_INSIDE_NMI_MASK);
120
121 /* Process a latched INIT or SMI, if any. */
122 kvm_make_request(KVM_REQ_EVENT, vcpu);
123
124 /*
125 * Even if KVM_SET_SREGS2 loaded PDPTRs out of band,
126 * on SMM exit we still need to reload them from
127 * guest memory
128 */
129 vcpu->arch.pdptrs_from_userspace = false;
130 }
131
132 kvm_mmu_reset_context(vcpu);
133 }
134
process_smi(struct kvm_vcpu * vcpu)135 void process_smi(struct kvm_vcpu *vcpu)
136 {
137 vcpu->arch.smi_pending = true;
138 kvm_make_request(KVM_REQ_EVENT, vcpu);
139 }
140
enter_smm_get_segment_flags(struct kvm_segment * seg)141 static u32 enter_smm_get_segment_flags(struct kvm_segment *seg)
142 {
143 u32 flags = 0;
144 flags |= seg->g << 23;
145 flags |= seg->db << 22;
146 flags |= seg->l << 21;
147 flags |= seg->avl << 20;
148 flags |= seg->present << 15;
149 flags |= seg->dpl << 13;
150 flags |= seg->s << 12;
151 flags |= seg->type << 8;
152 return flags;
153 }
154
enter_smm_save_seg_32(struct kvm_vcpu * vcpu,struct kvm_smm_seg_state_32 * state,u32 * selector,int n)155 static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu,
156 struct kvm_smm_seg_state_32 *state,
157 u32 *selector, int n)
158 {
159 struct kvm_segment seg;
160
161 kvm_get_segment(vcpu, &seg, n);
162 *selector = seg.selector;
163 state->base = seg.base;
164 state->limit = seg.limit;
165 state->flags = enter_smm_get_segment_flags(&seg);
166 }
167
168 #ifdef CONFIG_X86_64
enter_smm_save_seg_64(struct kvm_vcpu * vcpu,struct kvm_smm_seg_state_64 * state,int n)169 static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu,
170 struct kvm_smm_seg_state_64 *state,
171 int n)
172 {
173 struct kvm_segment seg;
174
175 kvm_get_segment(vcpu, &seg, n);
176 state->selector = seg.selector;
177 state->attributes = enter_smm_get_segment_flags(&seg) >> 8;
178 state->limit = seg.limit;
179 state->base = seg.base;
180 }
181 #endif
182
enter_smm_save_state_32(struct kvm_vcpu * vcpu,struct kvm_smram_state_32 * smram)183 static void enter_smm_save_state_32(struct kvm_vcpu *vcpu,
184 struct kvm_smram_state_32 *smram)
185 {
186 struct desc_ptr dt;
187 unsigned long val;
188 int i;
189
190 smram->cr0 = kvm_read_cr0(vcpu);
191 smram->cr3 = kvm_read_cr3(vcpu);
192 smram->eflags = kvm_get_rflags(vcpu);
193 smram->eip = kvm_rip_read(vcpu);
194
195 for (i = 0; i < 8; i++)
196 smram->gprs[i] = kvm_register_read_raw(vcpu, i);
197
198 kvm_get_dr(vcpu, 6, &val);
199 smram->dr6 = (u32)val;
200 kvm_get_dr(vcpu, 7, &val);
201 smram->dr7 = (u32)val;
202
203 enter_smm_save_seg_32(vcpu, &smram->tr, &smram->tr_sel, VCPU_SREG_TR);
204 enter_smm_save_seg_32(vcpu, &smram->ldtr, &smram->ldtr_sel, VCPU_SREG_LDTR);
205
206 static_call(kvm_x86_get_gdt)(vcpu, &dt);
207 smram->gdtr.base = dt.address;
208 smram->gdtr.limit = dt.size;
209
210 static_call(kvm_x86_get_idt)(vcpu, &dt);
211 smram->idtr.base = dt.address;
212 smram->idtr.limit = dt.size;
213
214 enter_smm_save_seg_32(vcpu, &smram->es, &smram->es_sel, VCPU_SREG_ES);
215 enter_smm_save_seg_32(vcpu, &smram->cs, &smram->cs_sel, VCPU_SREG_CS);
216 enter_smm_save_seg_32(vcpu, &smram->ss, &smram->ss_sel, VCPU_SREG_SS);
217
218 enter_smm_save_seg_32(vcpu, &smram->ds, &smram->ds_sel, VCPU_SREG_DS);
219 enter_smm_save_seg_32(vcpu, &smram->fs, &smram->fs_sel, VCPU_SREG_FS);
220 enter_smm_save_seg_32(vcpu, &smram->gs, &smram->gs_sel, VCPU_SREG_GS);
221
222 smram->cr4 = kvm_read_cr4(vcpu);
223 smram->smm_revision = 0x00020000;
224 smram->smbase = vcpu->arch.smbase;
225
226 smram->int_shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
227 }
228
229 #ifdef CONFIG_X86_64
enter_smm_save_state_64(struct kvm_vcpu * vcpu,struct kvm_smram_state_64 * smram)230 static void enter_smm_save_state_64(struct kvm_vcpu *vcpu,
231 struct kvm_smram_state_64 *smram)
232 {
233 struct desc_ptr dt;
234 unsigned long val;
235 int i;
236
237 for (i = 0; i < 16; i++)
238 smram->gprs[15 - i] = kvm_register_read_raw(vcpu, i);
239
240 smram->rip = kvm_rip_read(vcpu);
241 smram->rflags = kvm_get_rflags(vcpu);
242
243
244 kvm_get_dr(vcpu, 6, &val);
245 smram->dr6 = val;
246 kvm_get_dr(vcpu, 7, &val);
247 smram->dr7 = val;
248
249 smram->cr0 = kvm_read_cr0(vcpu);
250 smram->cr3 = kvm_read_cr3(vcpu);
251 smram->cr4 = kvm_read_cr4(vcpu);
252
253 smram->smbase = vcpu->arch.smbase;
254 smram->smm_revison = 0x00020064;
255
256 smram->efer = vcpu->arch.efer;
257
258 enter_smm_save_seg_64(vcpu, &smram->tr, VCPU_SREG_TR);
259
260 static_call(kvm_x86_get_idt)(vcpu, &dt);
261 smram->idtr.limit = dt.size;
262 smram->idtr.base = dt.address;
263
264 enter_smm_save_seg_64(vcpu, &smram->ldtr, VCPU_SREG_LDTR);
265
266 static_call(kvm_x86_get_gdt)(vcpu, &dt);
267 smram->gdtr.limit = dt.size;
268 smram->gdtr.base = dt.address;
269
270 enter_smm_save_seg_64(vcpu, &smram->es, VCPU_SREG_ES);
271 enter_smm_save_seg_64(vcpu, &smram->cs, VCPU_SREG_CS);
272 enter_smm_save_seg_64(vcpu, &smram->ss, VCPU_SREG_SS);
273 enter_smm_save_seg_64(vcpu, &smram->ds, VCPU_SREG_DS);
274 enter_smm_save_seg_64(vcpu, &smram->fs, VCPU_SREG_FS);
275 enter_smm_save_seg_64(vcpu, &smram->gs, VCPU_SREG_GS);
276
277 smram->int_shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
278 }
279 #endif
280
enter_smm(struct kvm_vcpu * vcpu)281 void enter_smm(struct kvm_vcpu *vcpu)
282 {
283 struct kvm_segment cs, ds;
284 struct desc_ptr dt;
285 unsigned long cr0;
286 union kvm_smram smram;
287
288 check_smram_offsets();
289
290 memset(smram.bytes, 0, sizeof(smram.bytes));
291
292 #ifdef CONFIG_X86_64
293 if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
294 enter_smm_save_state_64(vcpu, &smram.smram64);
295 else
296 #endif
297 enter_smm_save_state_32(vcpu, &smram.smram32);
298
299 /*
300 * Give enter_smm() a chance to make ISA-specific changes to the vCPU
301 * state (e.g. leave guest mode) after we've saved the state into the
302 * SMM state-save area.
303 *
304 * Kill the VM in the unlikely case of failure, because the VM
305 * can be in undefined state in this case.
306 */
307 if (static_call(kvm_x86_enter_smm)(vcpu, &smram))
308 goto error;
309
310 kvm_smm_changed(vcpu, true);
311
312 if (kvm_vcpu_write_guest(vcpu, vcpu->arch.smbase + 0xfe00, &smram, sizeof(smram)))
313 goto error;
314
315 if (static_call(kvm_x86_get_nmi_mask)(vcpu))
316 vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
317 else
318 static_call(kvm_x86_set_nmi_mask)(vcpu, true);
319
320 kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
321 kvm_rip_write(vcpu, 0x8000);
322
323 static_call(kvm_x86_set_interrupt_shadow)(vcpu, 0);
324
325 cr0 = vcpu->arch.cr0 & ~(X86_CR0_PE | X86_CR0_EM | X86_CR0_TS | X86_CR0_PG);
326 static_call(kvm_x86_set_cr0)(vcpu, cr0);
327 vcpu->arch.cr0 = cr0;
328
329 static_call(kvm_x86_set_cr4)(vcpu, 0);
330
331 /* Undocumented: IDT limit is set to zero on entry to SMM. */
332 dt.address = dt.size = 0;
333 static_call(kvm_x86_set_idt)(vcpu, &dt);
334
335 if (WARN_ON_ONCE(kvm_set_dr(vcpu, 7, DR7_FIXED_1)))
336 goto error;
337
338 cs.selector = (vcpu->arch.smbase >> 4) & 0xffff;
339 cs.base = vcpu->arch.smbase;
340
341 ds.selector = 0;
342 ds.base = 0;
343
344 cs.limit = ds.limit = 0xffffffff;
345 cs.type = ds.type = 0x3;
346 cs.dpl = ds.dpl = 0;
347 cs.db = ds.db = 0;
348 cs.s = ds.s = 1;
349 cs.l = ds.l = 0;
350 cs.g = ds.g = 1;
351 cs.avl = ds.avl = 0;
352 cs.present = ds.present = 1;
353 cs.unusable = ds.unusable = 0;
354 cs.padding = ds.padding = 0;
355
356 kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
357 kvm_set_segment(vcpu, &ds, VCPU_SREG_DS);
358 kvm_set_segment(vcpu, &ds, VCPU_SREG_ES);
359 kvm_set_segment(vcpu, &ds, VCPU_SREG_FS);
360 kvm_set_segment(vcpu, &ds, VCPU_SREG_GS);
361 kvm_set_segment(vcpu, &ds, VCPU_SREG_SS);
362
363 #ifdef CONFIG_X86_64
364 if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
365 if (static_call(kvm_x86_set_efer)(vcpu, 0))
366 goto error;
367 #endif
368
369 kvm_update_cpuid_runtime(vcpu);
370 kvm_mmu_reset_context(vcpu);
371 return;
372 error:
373 kvm_vm_dead(vcpu->kvm);
374 }
375
rsm_set_desc_flags(struct kvm_segment * desc,u32 flags)376 static void rsm_set_desc_flags(struct kvm_segment *desc, u32 flags)
377 {
378 desc->g = (flags >> 23) & 1;
379 desc->db = (flags >> 22) & 1;
380 desc->l = (flags >> 21) & 1;
381 desc->avl = (flags >> 20) & 1;
382 desc->present = (flags >> 15) & 1;
383 desc->dpl = (flags >> 13) & 3;
384 desc->s = (flags >> 12) & 1;
385 desc->type = (flags >> 8) & 15;
386
387 desc->unusable = !desc->present;
388 desc->padding = 0;
389 }
390
rsm_load_seg_32(struct kvm_vcpu * vcpu,const struct kvm_smm_seg_state_32 * state,u16 selector,int n)391 static int rsm_load_seg_32(struct kvm_vcpu *vcpu,
392 const struct kvm_smm_seg_state_32 *state,
393 u16 selector, int n)
394 {
395 struct kvm_segment desc;
396
397 desc.selector = selector;
398 desc.base = state->base;
399 desc.limit = state->limit;
400 rsm_set_desc_flags(&desc, state->flags);
401 kvm_set_segment(vcpu, &desc, n);
402 return X86EMUL_CONTINUE;
403 }
404
405 #ifdef CONFIG_X86_64
406
rsm_load_seg_64(struct kvm_vcpu * vcpu,const struct kvm_smm_seg_state_64 * state,int n)407 static int rsm_load_seg_64(struct kvm_vcpu *vcpu,
408 const struct kvm_smm_seg_state_64 *state,
409 int n)
410 {
411 struct kvm_segment desc;
412
413 desc.selector = state->selector;
414 rsm_set_desc_flags(&desc, state->attributes << 8);
415 desc.limit = state->limit;
416 desc.base = state->base;
417 kvm_set_segment(vcpu, &desc, n);
418 return X86EMUL_CONTINUE;
419 }
420 #endif
421
rsm_enter_protected_mode(struct kvm_vcpu * vcpu,u64 cr0,u64 cr3,u64 cr4)422 static int rsm_enter_protected_mode(struct kvm_vcpu *vcpu,
423 u64 cr0, u64 cr3, u64 cr4)
424 {
425 int bad;
426 u64 pcid;
427
428 /* In order to later set CR4.PCIDE, CR3[11:0] must be zero. */
429 pcid = 0;
430 if (cr4 & X86_CR4_PCIDE) {
431 pcid = cr3 & 0xfff;
432 cr3 &= ~0xfff;
433 }
434
435 bad = kvm_set_cr3(vcpu, cr3);
436 if (bad)
437 return X86EMUL_UNHANDLEABLE;
438
439 /*
440 * First enable PAE, long mode needs it before CR0.PG = 1 is set.
441 * Then enable protected mode. However, PCID cannot be enabled
442 * if EFER.LMA=0, so set it separately.
443 */
444 bad = kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PCIDE);
445 if (bad)
446 return X86EMUL_UNHANDLEABLE;
447
448 bad = kvm_set_cr0(vcpu, cr0);
449 if (bad)
450 return X86EMUL_UNHANDLEABLE;
451
452 if (cr4 & X86_CR4_PCIDE) {
453 bad = kvm_set_cr4(vcpu, cr4);
454 if (bad)
455 return X86EMUL_UNHANDLEABLE;
456 if (pcid) {
457 bad = kvm_set_cr3(vcpu, cr3 | pcid);
458 if (bad)
459 return X86EMUL_UNHANDLEABLE;
460 }
461
462 }
463
464 return X86EMUL_CONTINUE;
465 }
466
rsm_load_state_32(struct x86_emulate_ctxt * ctxt,const struct kvm_smram_state_32 * smstate)467 static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
468 const struct kvm_smram_state_32 *smstate)
469 {
470 struct kvm_vcpu *vcpu = ctxt->vcpu;
471 struct desc_ptr dt;
472 int i, r;
473
474 ctxt->eflags = smstate->eflags | X86_EFLAGS_FIXED;
475 ctxt->_eip = smstate->eip;
476
477 for (i = 0; i < 8; i++)
478 *reg_write(ctxt, i) = smstate->gprs[i];
479
480 if (kvm_set_dr(vcpu, 6, smstate->dr6))
481 return X86EMUL_UNHANDLEABLE;
482 if (kvm_set_dr(vcpu, 7, smstate->dr7))
483 return X86EMUL_UNHANDLEABLE;
484
485 rsm_load_seg_32(vcpu, &smstate->tr, smstate->tr_sel, VCPU_SREG_TR);
486 rsm_load_seg_32(vcpu, &smstate->ldtr, smstate->ldtr_sel, VCPU_SREG_LDTR);
487
488 dt.address = smstate->gdtr.base;
489 dt.size = smstate->gdtr.limit;
490 static_call(kvm_x86_set_gdt)(vcpu, &dt);
491
492 dt.address = smstate->idtr.base;
493 dt.size = smstate->idtr.limit;
494 static_call(kvm_x86_set_idt)(vcpu, &dt);
495
496 rsm_load_seg_32(vcpu, &smstate->es, smstate->es_sel, VCPU_SREG_ES);
497 rsm_load_seg_32(vcpu, &smstate->cs, smstate->cs_sel, VCPU_SREG_CS);
498 rsm_load_seg_32(vcpu, &smstate->ss, smstate->ss_sel, VCPU_SREG_SS);
499
500 rsm_load_seg_32(vcpu, &smstate->ds, smstate->ds_sel, VCPU_SREG_DS);
501 rsm_load_seg_32(vcpu, &smstate->fs, smstate->fs_sel, VCPU_SREG_FS);
502 rsm_load_seg_32(vcpu, &smstate->gs, smstate->gs_sel, VCPU_SREG_GS);
503
504 vcpu->arch.smbase = smstate->smbase;
505
506 r = rsm_enter_protected_mode(vcpu, smstate->cr0,
507 smstate->cr3, smstate->cr4);
508
509 if (r != X86EMUL_CONTINUE)
510 return r;
511
512 static_call(kvm_x86_set_interrupt_shadow)(vcpu, 0);
513 ctxt->interruptibility = (u8)smstate->int_shadow;
514
515 return r;
516 }
517
518 #ifdef CONFIG_X86_64
rsm_load_state_64(struct x86_emulate_ctxt * ctxt,const struct kvm_smram_state_64 * smstate)519 static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
520 const struct kvm_smram_state_64 *smstate)
521 {
522 struct kvm_vcpu *vcpu = ctxt->vcpu;
523 struct desc_ptr dt;
524 int i, r;
525
526 for (i = 0; i < 16; i++)
527 *reg_write(ctxt, i) = smstate->gprs[15 - i];
528
529 ctxt->_eip = smstate->rip;
530 ctxt->eflags = smstate->rflags | X86_EFLAGS_FIXED;
531
532 if (kvm_set_dr(vcpu, 6, smstate->dr6))
533 return X86EMUL_UNHANDLEABLE;
534 if (kvm_set_dr(vcpu, 7, smstate->dr7))
535 return X86EMUL_UNHANDLEABLE;
536
537 vcpu->arch.smbase = smstate->smbase;
538
539 if (kvm_set_msr(vcpu, MSR_EFER, smstate->efer & ~EFER_LMA))
540 return X86EMUL_UNHANDLEABLE;
541
542 rsm_load_seg_64(vcpu, &smstate->tr, VCPU_SREG_TR);
543
544 dt.size = smstate->idtr.limit;
545 dt.address = smstate->idtr.base;
546 static_call(kvm_x86_set_idt)(vcpu, &dt);
547
548 rsm_load_seg_64(vcpu, &smstate->ldtr, VCPU_SREG_LDTR);
549
550 dt.size = smstate->gdtr.limit;
551 dt.address = smstate->gdtr.base;
552 static_call(kvm_x86_set_gdt)(vcpu, &dt);
553
554 r = rsm_enter_protected_mode(vcpu, smstate->cr0, smstate->cr3, smstate->cr4);
555 if (r != X86EMUL_CONTINUE)
556 return r;
557
558 rsm_load_seg_64(vcpu, &smstate->es, VCPU_SREG_ES);
559 rsm_load_seg_64(vcpu, &smstate->cs, VCPU_SREG_CS);
560 rsm_load_seg_64(vcpu, &smstate->ss, VCPU_SREG_SS);
561 rsm_load_seg_64(vcpu, &smstate->ds, VCPU_SREG_DS);
562 rsm_load_seg_64(vcpu, &smstate->fs, VCPU_SREG_FS);
563 rsm_load_seg_64(vcpu, &smstate->gs, VCPU_SREG_GS);
564
565 static_call(kvm_x86_set_interrupt_shadow)(vcpu, 0);
566 ctxt->interruptibility = (u8)smstate->int_shadow;
567
568 return X86EMUL_CONTINUE;
569 }
570 #endif
571
emulator_leave_smm(struct x86_emulate_ctxt * ctxt)572 int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
573 {
574 struct kvm_vcpu *vcpu = ctxt->vcpu;
575 unsigned long cr0;
576 union kvm_smram smram;
577 u64 smbase;
578 int ret;
579
580 smbase = vcpu->arch.smbase;
581
582 ret = kvm_vcpu_read_guest(vcpu, smbase + 0xfe00, smram.bytes, sizeof(smram));
583 if (ret < 0)
584 return X86EMUL_UNHANDLEABLE;
585
586 if ((vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK) == 0)
587 static_call(kvm_x86_set_nmi_mask)(vcpu, false);
588
589 kvm_smm_changed(vcpu, false);
590
591 /*
592 * Get back to real mode, to prepare a safe state in which to load
593 * CR0/CR3/CR4/EFER. It's all a bit more complicated if the vCPU
594 * supports long mode.
595 */
596 #ifdef CONFIG_X86_64
597 if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {
598 struct kvm_segment cs_desc;
599 unsigned long cr4;
600
601 /* Zero CR4.PCIDE before CR0.PG. */
602 cr4 = kvm_read_cr4(vcpu);
603 if (cr4 & X86_CR4_PCIDE)
604 kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PCIDE);
605
606 /* A 32-bit code segment is required to clear EFER.LMA. */
607 memset(&cs_desc, 0, sizeof(cs_desc));
608 cs_desc.type = 0xb;
609 cs_desc.s = cs_desc.g = cs_desc.present = 1;
610 kvm_set_segment(vcpu, &cs_desc, VCPU_SREG_CS);
611 }
612 #endif
613
614 /* For the 64-bit case, this will clear EFER.LMA. */
615 cr0 = kvm_read_cr0(vcpu);
616 if (cr0 & X86_CR0_PE)
617 kvm_set_cr0(vcpu, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
618
619 #ifdef CONFIG_X86_64
620 if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {
621 unsigned long cr4, efer;
622
623 /* Clear CR4.PAE before clearing EFER.LME. */
624 cr4 = kvm_read_cr4(vcpu);
625 if (cr4 & X86_CR4_PAE)
626 kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PAE);
627
628 /* And finally go back to 32-bit mode. */
629 efer = 0;
630 kvm_set_msr(vcpu, MSR_EFER, efer);
631 }
632 #endif
633
634 /*
635 * Give leave_smm() a chance to make ISA-specific changes to the vCPU
636 * state (e.g. enter guest mode) before loading state from the SMM
637 * state-save area.
638 */
639 if (static_call(kvm_x86_leave_smm)(vcpu, &smram))
640 return X86EMUL_UNHANDLEABLE;
641
642 #ifdef CONFIG_X86_64
643 if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
644 return rsm_load_state_64(ctxt, &smram.smram64);
645 else
646 #endif
647 return rsm_load_state_32(ctxt, &smram.smram32);
648 }
649