xref: /openbmc/linux/arch/x86/kvm/x86.h (revision 6e10e219)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef ARCH_X86_KVM_X86_H
3 #define ARCH_X86_KVM_X86_H
4 
5 #include <linux/kvm_host.h>
6 #include <asm/mce.h>
7 #include <asm/pvclock.h>
8 #include "kvm_cache_regs.h"
9 #include "kvm_emulate.h"
10 
11 void kvm_spurious_fault(void);
12 
13 static __always_inline void kvm_guest_enter_irqoff(void)
14 {
15 	/*
16 	 * VMENTER enables interrupts (host state), but the kernel state is
17 	 * interrupts disabled when this is invoked. Also tell RCU about
18 	 * it. This is the same logic as for exit_to_user_mode().
19 	 *
20 	 * This ensures that e.g. latency analysis on the host observes
21 	 * guest mode as interrupt enabled.
22 	 *
23 	 * guest_enter_irqoff() informs context tracking about the
24 	 * transition to guest mode and if enabled adjusts RCU state
25 	 * accordingly.
26 	 */
27 	instrumentation_begin();
28 	trace_hardirqs_on_prepare();
29 	lockdep_hardirqs_on_prepare(CALLER_ADDR0);
30 	instrumentation_end();
31 
32 	guest_enter_irqoff();
33 	lockdep_hardirqs_on(CALLER_ADDR0);
34 }
35 
36 static __always_inline void kvm_guest_exit_irqoff(void)
37 {
38 	/*
39 	 * VMEXIT disables interrupts (host state), but tracing and lockdep
40 	 * have them in state 'on' as recorded before entering guest mode.
41 	 * Same as enter_from_user_mode().
42 	 *
43 	 * context_tracking_guest_exit() restores host context and reinstates
44 	 * RCU if enabled and required.
45 	 *
46 	 * This needs to be done immediately after VM-Exit, before any code
47 	 * that might contain tracepoints or call out to the greater world,
48 	 * e.g. before x86_spec_ctrl_restore_host().
49 	 */
50 	lockdep_hardirqs_off(CALLER_ADDR0);
51 	context_tracking_guest_exit();
52 
53 	instrumentation_begin();
54 	trace_hardirqs_off_finish();
55 	instrumentation_end();
56 }
57 
58 #define KVM_NESTED_VMENTER_CONSISTENCY_CHECK(consistency_check)		\
59 ({									\
60 	bool failed = (consistency_check);				\
61 	if (failed)							\
62 		trace_kvm_nested_vmenter_failed(#consistency_check, 0);	\
63 	failed;								\
64 })
65 
66 #define KVM_DEFAULT_PLE_GAP		128
67 #define KVM_VMX_DEFAULT_PLE_WINDOW	4096
68 #define KVM_DEFAULT_PLE_WINDOW_GROW	2
69 #define KVM_DEFAULT_PLE_WINDOW_SHRINK	0
70 #define KVM_VMX_DEFAULT_PLE_WINDOW_MAX	UINT_MAX
71 #define KVM_SVM_DEFAULT_PLE_WINDOW_MAX	USHRT_MAX
72 #define KVM_SVM_DEFAULT_PLE_WINDOW	3000
73 
74 static inline unsigned int __grow_ple_window(unsigned int val,
75 		unsigned int base, unsigned int modifier, unsigned int max)
76 {
77 	u64 ret = val;
78 
79 	if (modifier < 1)
80 		return base;
81 
82 	if (modifier < base)
83 		ret *= modifier;
84 	else
85 		ret += modifier;
86 
87 	return min(ret, (u64)max);
88 }
89 
90 static inline unsigned int __shrink_ple_window(unsigned int val,
91 		unsigned int base, unsigned int modifier, unsigned int min)
92 {
93 	if (modifier < 1)
94 		return base;
95 
96 	if (modifier < base)
97 		val /= modifier;
98 	else
99 		val -= modifier;
100 
101 	return max(val, min);
102 }
103 
104 #define MSR_IA32_CR_PAT_DEFAULT  0x0007040600070406ULL
105 
106 void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu);
107 int kvm_check_nested_events(struct kvm_vcpu *vcpu);
108 
109 static inline void kvm_clear_exception_queue(struct kvm_vcpu *vcpu)
110 {
111 	vcpu->arch.exception.pending = false;
112 	vcpu->arch.exception.injected = false;
113 }
114 
115 static inline void kvm_queue_interrupt(struct kvm_vcpu *vcpu, u8 vector,
116 	bool soft)
117 {
118 	vcpu->arch.interrupt.injected = true;
119 	vcpu->arch.interrupt.soft = soft;
120 	vcpu->arch.interrupt.nr = vector;
121 }
122 
123 static inline void kvm_clear_interrupt_queue(struct kvm_vcpu *vcpu)
124 {
125 	vcpu->arch.interrupt.injected = false;
126 }
127 
128 static inline bool kvm_event_needs_reinjection(struct kvm_vcpu *vcpu)
129 {
130 	return vcpu->arch.exception.injected || vcpu->arch.interrupt.injected ||
131 		vcpu->arch.nmi_injected;
132 }
133 
134 static inline bool kvm_exception_is_soft(unsigned int nr)
135 {
136 	return (nr == BP_VECTOR) || (nr == OF_VECTOR);
137 }
138 
139 static inline bool is_protmode(struct kvm_vcpu *vcpu)
140 {
141 	return kvm_read_cr0_bits(vcpu, X86_CR0_PE);
142 }
143 
144 static inline int is_long_mode(struct kvm_vcpu *vcpu)
145 {
146 #ifdef CONFIG_X86_64
147 	return vcpu->arch.efer & EFER_LMA;
148 #else
149 	return 0;
150 #endif
151 }
152 
153 static inline bool is_64_bit_mode(struct kvm_vcpu *vcpu)
154 {
155 	int cs_db, cs_l;
156 
157 	WARN_ON_ONCE(vcpu->arch.guest_state_protected);
158 
159 	if (!is_long_mode(vcpu))
160 		return false;
161 	static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l);
162 	return cs_l;
163 }
164 
165 static inline bool is_64_bit_hypercall(struct kvm_vcpu *vcpu)
166 {
167 	/*
168 	 * If running with protected guest state, the CS register is not
169 	 * accessible. The hypercall register values will have had to been
170 	 * provided in 64-bit mode, so assume the guest is in 64-bit.
171 	 */
172 	return vcpu->arch.guest_state_protected || is_64_bit_mode(vcpu);
173 }
174 
175 static inline bool x86_exception_has_error_code(unsigned int vector)
176 {
177 	static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
178 			BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
179 			BIT(PF_VECTOR) | BIT(AC_VECTOR);
180 
181 	return (1U << vector) & exception_has_error_code;
182 }
183 
184 static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
185 {
186 	return vcpu->arch.walk_mmu == &vcpu->arch.nested_mmu;
187 }
188 
189 static inline int is_pae(struct kvm_vcpu *vcpu)
190 {
191 	return kvm_read_cr4_bits(vcpu, X86_CR4_PAE);
192 }
193 
194 static inline int is_pse(struct kvm_vcpu *vcpu)
195 {
196 	return kvm_read_cr4_bits(vcpu, X86_CR4_PSE);
197 }
198 
199 static inline int is_paging(struct kvm_vcpu *vcpu)
200 {
201 	return likely(kvm_read_cr0_bits(vcpu, X86_CR0_PG));
202 }
203 
204 static inline bool is_pae_paging(struct kvm_vcpu *vcpu)
205 {
206 	return !is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu);
207 }
208 
209 static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu)
210 {
211 	return kvm_read_cr4_bits(vcpu, X86_CR4_LA57) ? 57 : 48;
212 }
213 
214 static inline u64 get_canonical(u64 la, u8 vaddr_bits)
215 {
216 	return ((int64_t)la << (64 - vaddr_bits)) >> (64 - vaddr_bits);
217 }
218 
219 static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu)
220 {
221 	return get_canonical(la, vcpu_virt_addr_bits(vcpu)) != la;
222 }
223 
224 static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu,
225 					gva_t gva, gfn_t gfn, unsigned access)
226 {
227 	u64 gen = kvm_memslots(vcpu->kvm)->generation;
228 
229 	if (unlikely(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS))
230 		return;
231 
232 	/*
233 	 * If this is a shadow nested page table, the "GVA" is
234 	 * actually a nGPA.
235 	 */
236 	vcpu->arch.mmio_gva = mmu_is_nested(vcpu) ? 0 : gva & PAGE_MASK;
237 	vcpu->arch.mmio_access = access;
238 	vcpu->arch.mmio_gfn = gfn;
239 	vcpu->arch.mmio_gen = gen;
240 }
241 
242 static inline bool vcpu_match_mmio_gen(struct kvm_vcpu *vcpu)
243 {
244 	return vcpu->arch.mmio_gen == kvm_memslots(vcpu->kvm)->generation;
245 }
246 
247 /*
248  * Clear the mmio cache info for the given gva. If gva is MMIO_GVA_ANY, we
249  * clear all mmio cache info.
250  */
251 #define MMIO_GVA_ANY (~(gva_t)0)
252 
253 static inline void vcpu_clear_mmio_info(struct kvm_vcpu *vcpu, gva_t gva)
254 {
255 	if (gva != MMIO_GVA_ANY && vcpu->arch.mmio_gva != (gva & PAGE_MASK))
256 		return;
257 
258 	vcpu->arch.mmio_gva = 0;
259 }
260 
261 static inline bool vcpu_match_mmio_gva(struct kvm_vcpu *vcpu, unsigned long gva)
262 {
263 	if (vcpu_match_mmio_gen(vcpu) && vcpu->arch.mmio_gva &&
264 	      vcpu->arch.mmio_gva == (gva & PAGE_MASK))
265 		return true;
266 
267 	return false;
268 }
269 
270 static inline bool vcpu_match_mmio_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
271 {
272 	if (vcpu_match_mmio_gen(vcpu) && vcpu->arch.mmio_gfn &&
273 	      vcpu->arch.mmio_gfn == gpa >> PAGE_SHIFT)
274 		return true;
275 
276 	return false;
277 }
278 
279 static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, int reg)
280 {
281 	unsigned long val = kvm_register_read_raw(vcpu, reg);
282 
283 	return is_64_bit_mode(vcpu) ? val : (u32)val;
284 }
285 
286 static inline void kvm_register_write(struct kvm_vcpu *vcpu,
287 				       int reg, unsigned long val)
288 {
289 	if (!is_64_bit_mode(vcpu))
290 		val = (u32)val;
291 	return kvm_register_write_raw(vcpu, reg, val);
292 }
293 
294 static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk)
295 {
296 	return !(kvm->arch.disabled_quirks & quirk);
297 }
298 
299 static inline bool kvm_vcpu_latch_init(struct kvm_vcpu *vcpu)
300 {
301 	return is_smm(vcpu) || static_call(kvm_x86_apic_init_signal_blocked)(vcpu);
302 }
303 
304 void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip);
305 
306 u64 get_kvmclock_ns(struct kvm *kvm);
307 
308 int kvm_read_guest_virt(struct kvm_vcpu *vcpu,
309 	gva_t addr, void *val, unsigned int bytes,
310 	struct x86_exception *exception);
311 
312 int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu,
313 	gva_t addr, void *val, unsigned int bytes,
314 	struct x86_exception *exception);
315 
316 int handle_ud(struct kvm_vcpu *vcpu);
317 
318 void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu);
319 
320 void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu);
321 u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn);
322 bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data);
323 int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data);
324 int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
325 bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn,
326 					  int page_num);
327 bool kvm_vector_hashing_enabled(void);
328 void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code);
329 int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
330 				    void *insn, int insn_len);
331 int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
332 			    int emulation_type, void *insn, int insn_len);
333 fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu);
334 
335 extern u64 host_xcr0;
336 extern u64 supported_xcr0;
337 extern u64 host_xss;
338 extern u64 supported_xss;
339 
340 static inline bool kvm_mpx_supported(void)
341 {
342 	return (supported_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
343 		== (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
344 }
345 
346 extern unsigned int min_timer_period_us;
347 
348 extern bool enable_vmware_backdoor;
349 
350 extern int pi_inject_timer;
351 
352 extern bool report_ignored_msrs;
353 
354 static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec)
355 {
356 	return pvclock_scale_delta(nsec, vcpu->arch.virtual_tsc_mult,
357 				   vcpu->arch.virtual_tsc_shift);
358 }
359 
360 /* Same "calling convention" as do_div:
361  * - divide (n << 32) by base
362  * - put result in n
363  * - return remainder
364  */
365 #define do_shl32_div32(n, base)					\
366 	({							\
367 	    u32 __quot, __rem;					\
368 	    asm("divl %2" : "=a" (__quot), "=d" (__rem)		\
369 			: "rm" (base), "0" (0), "1" ((u32) n));	\
370 	    n = __quot;						\
371 	    __rem;						\
372 	 })
373 
374 static inline bool kvm_mwait_in_guest(struct kvm *kvm)
375 {
376 	return kvm->arch.mwait_in_guest;
377 }
378 
379 static inline bool kvm_hlt_in_guest(struct kvm *kvm)
380 {
381 	return kvm->arch.hlt_in_guest;
382 }
383 
384 static inline bool kvm_pause_in_guest(struct kvm *kvm)
385 {
386 	return kvm->arch.pause_in_guest;
387 }
388 
389 static inline bool kvm_cstate_in_guest(struct kvm *kvm)
390 {
391 	return kvm->arch.cstate_in_guest;
392 }
393 
394 enum kvm_intr_type {
395 	/* Values are arbitrary, but must be non-zero. */
396 	KVM_HANDLING_IRQ = 1,
397 	KVM_HANDLING_NMI,
398 };
399 
400 static inline void kvm_before_interrupt(struct kvm_vcpu *vcpu,
401 					enum kvm_intr_type intr)
402 {
403 	WRITE_ONCE(vcpu->arch.handling_intr_from_guest, (u8)intr);
404 }
405 
406 static inline void kvm_after_interrupt(struct kvm_vcpu *vcpu)
407 {
408 	WRITE_ONCE(vcpu->arch.handling_intr_from_guest, 0);
409 }
410 
411 static inline bool kvm_handling_nmi_from_guest(struct kvm_vcpu *vcpu)
412 {
413 	return vcpu->arch.handling_intr_from_guest == KVM_HANDLING_NMI;
414 }
415 
416 static inline bool kvm_pat_valid(u64 data)
417 {
418 	if (data & 0xF8F8F8F8F8F8F8F8ull)
419 		return false;
420 	/* 0, 1, 4, 5, 6, 7 are valid values.  */
421 	return (data | ((data & 0x0202020202020202ull) << 1)) == data;
422 }
423 
424 static inline bool kvm_dr7_valid(u64 data)
425 {
426 	/* Bits [63:32] are reserved */
427 	return !(data >> 32);
428 }
429 static inline bool kvm_dr6_valid(u64 data)
430 {
431 	/* Bits [63:32] are reserved */
432 	return !(data >> 32);
433 }
434 
435 /*
436  * Trigger machine check on the host. We assume all the MSRs are already set up
437  * by the CPU and that we still run on the same CPU as the MCE occurred on.
438  * We pass a fake environment to the machine check handler because we want
439  * the guest to be always treated like user space, no matter what context
440  * it used internally.
441  */
442 static inline void kvm_machine_check(void)
443 {
444 #if defined(CONFIG_X86_MCE)
445 	struct pt_regs regs = {
446 		.cs = 3, /* Fake ring 3 no matter what the guest ran on */
447 		.flags = X86_EFLAGS_IF,
448 	};
449 
450 	do_machine_check(&regs);
451 #endif
452 }
453 
454 void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu);
455 void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu);
456 int kvm_spec_ctrl_test_value(u64 value);
457 bool kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
458 int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r,
459 			      struct x86_exception *e);
460 int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva);
461 bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type);
462 
463 /*
464  * Internal error codes that are used to indicate that MSR emulation encountered
465  * an error that should result in #GP in the guest, unless userspace
466  * handles it.
467  */
468 #define  KVM_MSR_RET_INVALID	2	/* in-kernel MSR emulation #GP condition */
469 #define  KVM_MSR_RET_FILTERED	3	/* #GP due to userspace MSR filter */
470 
471 #define __cr4_reserved_bits(__cpu_has, __c)             \
472 ({                                                      \
473 	u64 __reserved_bits = CR4_RESERVED_BITS;        \
474                                                         \
475 	if (!__cpu_has(__c, X86_FEATURE_XSAVE))         \
476 		__reserved_bits |= X86_CR4_OSXSAVE;     \
477 	if (!__cpu_has(__c, X86_FEATURE_SMEP))          \
478 		__reserved_bits |= X86_CR4_SMEP;        \
479 	if (!__cpu_has(__c, X86_FEATURE_SMAP))          \
480 		__reserved_bits |= X86_CR4_SMAP;        \
481 	if (!__cpu_has(__c, X86_FEATURE_FSGSBASE))      \
482 		__reserved_bits |= X86_CR4_FSGSBASE;    \
483 	if (!__cpu_has(__c, X86_FEATURE_PKU))           \
484 		__reserved_bits |= X86_CR4_PKE;         \
485 	if (!__cpu_has(__c, X86_FEATURE_LA57))          \
486 		__reserved_bits |= X86_CR4_LA57;        \
487 	if (!__cpu_has(__c, X86_FEATURE_UMIP))          \
488 		__reserved_bits |= X86_CR4_UMIP;        \
489 	if (!__cpu_has(__c, X86_FEATURE_VMX))           \
490 		__reserved_bits |= X86_CR4_VMXE;        \
491 	if (!__cpu_has(__c, X86_FEATURE_PCID))          \
492 		__reserved_bits |= X86_CR4_PCIDE;       \
493 	__reserved_bits;                                \
494 })
495 
496 int kvm_sev_es_mmio_write(struct kvm_vcpu *vcpu, gpa_t src, unsigned int bytes,
497 			  void *dst);
498 int kvm_sev_es_mmio_read(struct kvm_vcpu *vcpu, gpa_t src, unsigned int bytes,
499 			 void *dst);
500 int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
501 			 unsigned int port, void *data,  unsigned int count,
502 			 int in);
503 
504 #endif
505