VirtualBox

source: vbox/trunk/src/VBox/VMM/VMMR0/CPUMR0.cpp@ 16103

Last change on this file since 16103 was 16103, checked in by vboxsync, 16 years ago

CPUMR0.cpp: minus RTLogPrintf.

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1/* $Id: CPUMR0.cpp 16103 2009-01-20 21:46:18Z vboxsync $ */
2/** @file
3 * CPUM - Host Context Ring 0.
4 */
5
6/*
7 * Copyright (C) 2006-2007 Sun Microsystems, Inc.
8 *
9 * This file is part of VirtualBox Open Source Edition (OSE), as
10 * available from http://www.virtualbox.org. This file is free software;
11 * you can redistribute it and/or modify it under the terms of the GNU
12 * General Public License (GPL) as published by the Free Software
13 * Foundation, in version 2 as it comes in the "COPYING" file of the
14 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16 *
17 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
18 * Clara, CA 95054 USA or visit http://www.sun.com if you need
19 * additional information or have any questions.
20 */
21
22
23/*******************************************************************************
24* Header Files *
25*******************************************************************************/
26#define LOG_GROUP LOG_GROUP_CPUM
27#include <VBox/cpum.h>
28#include "CPUMInternal.h"
29#include <VBox/vm.h>
30#include <VBox/x86.h>
31#include <VBox/err.h>
32#include <VBox/log.h>
33#include <VBox/hwaccm.h>
34#include <iprt/assert.h>
35#include <iprt/asm.h>
36
37
38
39/**
40 * Does Ring-0 CPUM initialization.
41 *
42 * This is mainly to check that the Host CPU mode is compatible
43 * with VBox.
44 *
45 * @returns VBox status code.
46 * @param pVM The VM to operate on.
47 */
48VMMR0DECL(int) CPUMR0Init(PVM pVM)
49{
50 LogFlow(("CPUMR0Init: %p\n", pVM));
51
52 /*
53 * Check CR0 & CR4 flags.
54 */
55 uint32_t u32CR0 = ASMGetCR0();
56 if ((u32CR0 & (X86_CR0_PE | X86_CR0_PG)) != (X86_CR0_PE | X86_CR0_PG)) /* a bit paranoid perhaps.. */
57 {
58 Log(("CPUMR0Init: PE or PG not set. cr0=%#x\n", u32CR0));
59 return VERR_UNSUPPORTED_CPU_MODE;
60 }
61
62 /*
63 * Check for sysenter if it's used.
64 */
65 if (ASMHasCpuId())
66 {
67 uint32_t u32CpuVersion;
68 uint32_t u32Dummy;
69 uint32_t u32Features;
70 ASMCpuId(1, &u32CpuVersion, &u32Dummy, &u32Dummy, &u32Features);
71 uint32_t u32Family = u32CpuVersion >> 8;
72 uint32_t u32Model = (u32CpuVersion >> 4) & 0xF;
73 uint32_t u32Stepping = u32CpuVersion & 0xF;
74
75 /*
76 * Intel docs claim you should test both the flag and family, model & stepping.
77 * Some Pentium Pro cpus have the SEP cpuid flag set, but don't support it.
78 */
79 if ( (u32Features & X86_CPUID_FEATURE_EDX_SEP)
80 && !(u32Family == 6 && u32Model < 3 && u32Stepping < 3))
81 {
82 /*
83 * Read the MSR and see if it's in use or not.
84 */
85 uint32_t u32 = ASMRdMsr_Low(MSR_IA32_SYSENTER_CS);
86 if (u32)
87 {
88 for (unsigned i=0;i<pVM->cCPUs;i++)
89 pVM->aCpus[i].cpum.s.fUseFlags |= CPUM_USE_SYSENTER;
90
91 Log(("CPUMR0Init: host uses sysenter cs=%08x%08x\n", ASMRdMsr_High(MSR_IA32_SYSENTER_CS), u32));
92 }
93 }
94
95 /** @todo check for AMD and syscall!!!!!! */
96 }
97
98
99 /*
100 * Check if debug registers are armed.
101 * This ASSUMES that DR7.GD is not set, or that it's handled transparently!
102 */
103 uint32_t u32DR7 = ASMGetDR7();
104 if (u32DR7 & X86_DR7_ENABLED_MASK)
105 {
106 for (unsigned i=0;i<pVM->cCPUs;i++)
107 pVM->aCpus[i].cpum.s.fUseFlags |= CPUM_USE_DEBUG_REGS_HOST;
108 Log(("CPUMR0Init: host uses debug registers (dr7=%x)\n", u32DR7));
109 }
110
111 return VINF_SUCCESS;
112}
113
114
115/**
116 * Lazily sync in the FPU/XMM state
117 *
118 * @returns VBox status code.
119 * @param pVM VM handle.
120 * @param pVCpu VMCPU handle.
121 * @param pCtx CPU context
122 */
123VMMR0DECL(int) CPUMR0LoadGuestFPU(PVM pVM, PVMCPU pVCpu, PCPUMCTX pCtx)
124{
125 Assert(pVM->cpum.s.CPUFeatures.edx.u1FXSR);
126 Assert(ASMGetCR4() & X86_CR4_OSFSXR);
127
128 /* If the FPU state has already been loaded, then it's a guest trap. */
129 if (pVCpu->cpum.s.fUseFlags & CPUM_USED_FPU)
130 {
131 Assert( ((pCtx->cr0 & (X86_CR0_MP | X86_CR0_EM | X86_CR0_TS)) == (X86_CR0_MP | X86_CR0_EM | X86_CR0_TS))
132 || ((pCtx->cr0 & (X86_CR0_MP | X86_CR0_EM | X86_CR0_TS)) == (X86_CR0_MP | X86_CR0_TS)));
133 return VINF_EM_RAW_GUEST_TRAP;
134 }
135
136 /*
137 * There are two basic actions:
138 * 1. Save host fpu and restore guest fpu.
139 * 2. Generate guest trap.
140 *
141 * When entering the hypervisor we'll always enable MP (for proper wait
142 * trapping) and TS (for intercepting all fpu/mmx/sse stuff). The EM flag
143 * is taken from the guest OS in order to get proper SSE handling.
144 *
145 *
146 * Actions taken depending on the guest CR0 flags:
147 *
148 * 3 2 1
149 * TS | EM | MP | FPUInstr | WAIT :: VMM Action
150 * ------------------------------------------------------------------------
151 * 0 | 0 | 0 | Exec | Exec :: Clear TS & MP, Save HC, Load GC.
152 * 0 | 0 | 1 | Exec | Exec :: Clear TS, Save HC, Load GC.
153 * 0 | 1 | 0 | #NM | Exec :: Clear TS & MP, Save HC, Load GC.
154 * 0 | 1 | 1 | #NM | Exec :: Clear TS, Save HC, Load GC.
155 * 1 | 0 | 0 | #NM | Exec :: Clear MP, Save HC, Load GC. (EM is already cleared.)
156 * 1 | 0 | 1 | #NM | #NM :: Go to guest taking trap there.
157 * 1 | 1 | 0 | #NM | Exec :: Clear MP, Save HC, Load GC. (EM is already set.)
158 * 1 | 1 | 1 | #NM | #NM :: Go to guest taking trap there.
159 */
160
161 switch (pCtx->cr0 & (X86_CR0_MP | X86_CR0_EM | X86_CR0_TS))
162 {
163 case X86_CR0_MP | X86_CR0_TS:
164 case X86_CR0_MP | X86_CR0_EM | X86_CR0_TS:
165 return VINF_EM_RAW_GUEST_TRAP;
166 default:
167 break;
168 }
169
170#if HC_ARCH_BITS == 32 && defined(VBOX_WITH_64_BITS_GUESTS) && !defined(VBOX_WITH_HYBRID_32BIT_KERNEL)
171 if (CPUMIsGuestInLongModeEx(pCtx))
172 {
173 /* Restore the state on entry as we need to be in 64 bits mode to access the full state. */
174 pVCpu->cpum.s.fUseFlags |= CPUM_SYNC_FPU_STATE;
175 }
176 else
177#endif
178 {
179#ifndef CPUM_CAN_HANDLE_NM_TRAPS_IN_KERNEL_MODE
180 uint64_t oldMsrEFERHost = 0;
181 uint32_t oldCR0 = ASMGetCR0();
182
183 /* Clear MSR_K6_EFER_FFXSR or else we'll be unable to save/restore the XMM state with fxsave/fxrstor. */
184 if (pVM->cpum.s.CPUFeaturesExt.edx & X86_CPUID_AMD_FEATURE_EDX_FFXSR)
185 {
186 /** @todo Do we really need to read this every time?? The host could change this on the fly though.
187 * bird: what about starting by skipping the ASMWrMsr below if we didn't
188 * change anything? Ditto for the stuff in CPUMR0SaveGuestFPU. */
189 oldMsrEFERHost = ASMRdMsr(MSR_K6_EFER);
190 if (oldMsrEFERHost & MSR_K6_EFER_FFXSR)
191 {
192 ASMWrMsr(MSR_K6_EFER, oldMsrEFERHost & ~MSR_K6_EFER_FFXSR);
193 pVCpu->cpum.s.fUseFlags |= CPUM_MANUAL_XMM_RESTORE;
194 }
195 }
196
197 /* If we sync the FPU/XMM state on-demand, then we can continue execution as if nothing has happened. */
198 int rc = CPUMHandleLazyFPU(pVM, pVCpu);
199 AssertRC(rc);
200 Assert(CPUMIsGuestFPUStateActive(pVCpu));
201
202 /* Restore EFER MSR */
203 if (pVCpu->cpum.s.fUseFlags & CPUM_MANUAL_XMM_RESTORE)
204 ASMWrMsr(MSR_K6_EFER, oldMsrEFERHost);
205
206 /* CPUMHandleLazyFPU could have changed CR0; restore it. */
207 ASMSetCR0(oldCR0);
208
209#else /* CPUM_CAN_HANDLE_NM_TRAPS_IN_KERNEL_MODE */
210
211 /*
212 * Save the FPU control word and MXCSR, so we can restore the state properly afterwards.
213 * We don't want the guest to be able to trigger floating point/SSE exceptions on the host.
214 */
215 pVCpu->cpum.s.Host.fpu.FCW = CPUMGetFCW();
216 if (pVM->cpum.s.CPUFeatures.edx.u1SSE)
217 pVCpu->cpum.s.Host.fpu.MXCSR = CPUMGetMXCSR();
218
219 cpumR0LoadFPU(pCtx);
220
221 /*
222 * The MSR_K6_EFER_FFXSR feature is AMD only so far, but check the cpuid just in case Intel adds it in the future.
223 *
224 * MSR_K6_EFER_FFXSR changes the behaviour of fxsave and fxrstore: the XMM state isn't saved/restored
225 */
226 if (pVM->cpum.s.CPUFeaturesExt.edx & X86_CPUID_AMD_FEATURE_EDX_FFXSR)
227 {
228 /** @todo Do we really need to read this every time?? The host could change this on the fly though. */
229 uint64_t msrEFERHost = ASMRdMsr(MSR_K6_EFER);
230
231 if (msrEFERHost & MSR_K6_EFER_FFXSR)
232 {
233 /* fxrstor doesn't restore the XMM state! */
234 cpumR0LoadXMM(pCtx);
235 pVCpu->cpum.s.fUseFlags |= CPUM_MANUAL_XMM_RESTORE;
236 }
237 }
238#endif /* CPUM_CAN_HANDLE_NM_TRAPS_IN_KERNEL_MODE */
239 }
240
241 pVCpu->cpum.s.fUseFlags |= CPUM_USED_FPU;
242 return VINF_SUCCESS;
243}
244
245
246/**
247 * Save guest FPU/XMM state
248 *
249 * @returns VBox status code.
250 * @param pVM VM handle.
251 * @param pVCpu VMCPU handle.
252 * @param pCtx CPU context
253 */
254VMMR0DECL(int) CPUMR0SaveGuestFPU(PVM pVM, PVMCPU pVCpu, PCPUMCTX pCtx)
255{
256 Assert(pVM->cpum.s.CPUFeatures.edx.u1FXSR);
257 Assert(ASMGetCR4() & X86_CR4_OSFSXR);
258 AssertReturn((pVCpu->cpum.s.fUseFlags & CPUM_USED_FPU), VINF_SUCCESS);
259
260#if HC_ARCH_BITS == 32 && defined(VBOX_WITH_64_BITS_GUESTS) && !defined(VBOX_WITH_HYBRID_32BIT_KERNEL)
261 if (CPUMIsGuestInLongModeEx(pCtx))
262 {
263if (!(pVCpu->cpum.s.fUseFlags & CPUM_SYNC_FPU_STATE))
264 if (!(pVCpu->cpum.s.fUseFlags & CPUM_SYNC_FPU_STATE))
265 HWACCMR0SaveFPUState(pVM, pVCpu, pCtx);
266
267
268 cpumR0RestoreHostFPUState(&pVCpu->cpum.s);
269 }
270 else
271#endif
272 {
273#ifndef CPUM_CAN_HANDLE_NM_TRAPS_IN_KERNEL_MODE
274 uint64_t oldMsrEFERHost = 0;
275
276 /* Clear MSR_K6_EFER_FFXSR or else we'll be unable to save/restore the XMM state with fxsave/fxrstor. */
277 if (pVCpu->cpum.s.fUseFlags & CPUM_MANUAL_XMM_RESTORE)
278 {
279 oldMsrEFERHost = ASMRdMsr(MSR_K6_EFER);
280 ASMWrMsr(MSR_K6_EFER, oldMsrEFERHost & ~MSR_K6_EFER_FFXSR);
281 }
282 cpumR0SaveGuestRestoreHostFPUState(&pVCpu->cpum.s);
283
284 /* Restore EFER MSR */
285 if (pVCpu->cpum.s.fUseFlags & CPUM_MANUAL_XMM_RESTORE)
286 ASMWrMsr(MSR_K6_EFER, oldMsrEFERHost | MSR_K6_EFER_FFXSR);
287
288#else /* CPUM_CAN_HANDLE_NM_TRAPS_IN_KERNEL_MODE */
289 cpumR0SaveFPU(pCtx);
290 if (pVCpu->cpum.s.fUseFlags & CPUM_MANUAL_XMM_RESTORE)
291 {
292 /* fxsave doesn't save the XMM state! */
293 cpumR0SaveXMM(pCtx);
294 }
295
296 /*
297 * Restore the original FPU control word and MXCSR.
298 * We don't want the guest to be able to trigger floating point/SSE exceptions on the host.
299 */
300 cpumR0SetFCW(pVCpu->cpum.s.Host.fpu.FCW);
301 if (pVM->cpum.s.CPUFeatures.edx.u1SSE)
302 cpumR0SetMXCSR(pVCpu->cpum.s.Host.fpu.MXCSR);
303#endif /* CPUM_CAN_HANDLE_NM_TRAPS_IN_KERNEL_MODE */
304 }
305
306 pVCpu->cpum.s.fUseFlags &= ~(CPUM_USED_FPU | CPUM_MANUAL_XMM_RESTORE);
307 return VINF_SUCCESS;
308}
309
310
311/**
312 * Save guest debug state
313 *
314 * @returns VBox status code.
315 * @param pVM VM handle.
316 * @param pVCpu VMCPU handle.
317 * @param pCtx CPU context
318 * @param fDR6 Include DR6 or not
319 */
320VMMR0DECL(int) CPUMR0SaveGuestDebugState(PVM pVM, PVMCPU pVCpu, PCPUMCTX pCtx, bool fDR6)
321{
322 Assert(pVCpu->cpum.s.fUseFlags & CPUM_USE_DEBUG_REGS);
323
324 /* Save the guest's debug state. The caller is responsible for DR7. */
325#if HC_ARCH_BITS == 32 && defined(VBOX_WITH_64_BITS_GUESTS) && !defined(VBOX_WITH_HYBRID_32BIT_KERNEL)
326 if (CPUMIsGuestInLongModeEx(pCtx))
327 {
328 if (!(pVCpu->cpum.s.fUseFlags & CPUM_SYNC_DEBUG_STATE))
329 {
330 uint64_t dr6 = pCtx->dr[6];
331
332 HWACCMR0SaveDebugState(pVM, pVCpu, pCtx);
333 if (!fDR6) /* dr6 was already up-to-date */
334 pCtx->dr[6] = dr6;
335 }
336 }
337 else
338#endif
339 {
340#ifdef VBOX_WITH_HYBRID_32BIT_KERNEL
341 cpumR0SaveDRx(&pCtx->dr[0]);
342#else
343 pCtx->dr[0] = ASMGetDR0();
344 pCtx->dr[1] = ASMGetDR1();
345 pCtx->dr[2] = ASMGetDR2();
346 pCtx->dr[3] = ASMGetDR3();
347#endif
348 if (fDR6)
349 pCtx->dr[6] = ASMGetDR6();
350 }
351
352 /*
353 * Restore the host's debug state. DR0-3, DR6 and only then DR7!
354 * DR7 contains 0x400 right now.
355 */
356#ifdef VBOX_WITH_HYBRID_32BIT_KERNEL
357 AssertCompile((uintptr_t)&pVCpu->cpum.s.Host.dr3 - (uintptr_t)&pVCpu->cpum.s.Host.dr0 == sizeof(uint64_t) * 3);
358 cpumR0LoadDRx(&pVCpu->cpum.s.Host.dr0);
359#else
360 ASMSetDR0(pVCpu->cpum.s.Host.dr0);
361 ASMSetDR1(pVCpu->cpum.s.Host.dr1);
362 ASMSetDR2(pVCpu->cpum.s.Host.dr2);
363 ASMSetDR3(pVCpu->cpum.s.Host.dr3);
364#endif
365 ASMSetDR6(pVCpu->cpum.s.Host.dr6);
366 ASMSetDR7(pVCpu->cpum.s.Host.dr7);
367
368 pVCpu->cpum.s.fUseFlags &= ~CPUM_USE_DEBUG_REGS;
369 return VINF_SUCCESS;
370}
371
372
373/**
374 * Lazily sync in the debug state
375 *
376 * @returns VBox status code.
377 * @param pVM VM handle.
378 * @param pVCpu VMCPU handle.
379 * @param pCtx CPU context
380 * @param fDR6 Include DR6 or not
381 */
382VMMR0DECL(int) CPUMR0LoadGuestDebugState(PVM pVM, PVMCPU pVCpu, PCPUMCTX pCtx, bool fDR6)
383{
384 /* Save the host state. */
385#ifdef VBOX_WITH_HYBRID_32BIT_KERNEL
386 AssertCompile((uintptr_t)&pVCpu->cpum.s.Host.dr3 - (uintptr_t)&pVCpu->cpum.s.Host.dr0 == sizeof(uint64_t) * 3);
387 cpumR0SaveDRx(&pVCpu->cpum.s.Host.dr0);
388#else
389 pVCpu->cpum.s.Host.dr0 = ASMGetDR0();
390 pVCpu->cpum.s.Host.dr1 = ASMGetDR1();
391 pVCpu->cpum.s.Host.dr2 = ASMGetDR2();
392 pVCpu->cpum.s.Host.dr3 = ASMGetDR3();
393#endif
394 pVCpu->cpum.s.Host.dr6 = ASMGetDR6();
395 /** @todo dr7 might already have been changed to 0x400; don't care right now as it's harmless. */
396 pVCpu->cpum.s.Host.dr7 = ASMGetDR7();
397 /* Make sure DR7 is harmless or else we could trigger breakpoints when restoring dr0-3 (!) */
398 ASMSetDR7(X86_DR7_INIT_VAL);
399
400 /* Activate the guest state DR0-3; DR7 is left to the caller. */
401#if HC_ARCH_BITS == 32 && defined(VBOX_WITH_64_BITS_GUESTS) && !defined(VBOX_WITH_HYBRID_32BIT_KERNEL)
402 if (CPUMIsGuestInLongModeEx(pCtx))
403 {
404 /* Restore the state on entry as we need to be in 64 bits mode to access the full state. */
405 pVCpu->cpum.s.fUseFlags |= CPUM_SYNC_DEBUG_STATE;
406 }
407 else
408#endif
409 {
410#ifdef VBOX_WITH_HYBRID_32BIT_KERNEL
411 cpumR0LoadDRx(&pCtx->dr[0]);
412#else
413 ASMSetDR0(pCtx->dr[0]);
414 ASMSetDR1(pCtx->dr[1]);
415 ASMSetDR2(pCtx->dr[2]);
416 ASMSetDR3(pCtx->dr[3]);
417#endif
418 if (fDR6)
419 ASMSetDR6(pCtx->dr[6]);
420 }
421
422 pVCpu->cpum.s.fUseFlags |= CPUM_USE_DEBUG_REGS;
423 return VINF_SUCCESS;
424}
425
426
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