1 /*- 2 * Copyright (c) 2014, Neel Natu (neel@freebsd.org) 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/errno.h> 32 #include <sys/systm.h> 33 34 #include <machine/cpufunc.h> 35 #include <machine/specialreg.h> 36 #include <machine/vmm.h> 37 38 #include "svm.h" 39 #include "vmcb.h" 40 #include "svm_softc.h" 41 #include "svm_msr.h" 42 43 #ifndef MSR_AMDK8_IPM 44 #define MSR_AMDK8_IPM 0xc0010055 45 #endif 46 47 enum { 48 IDX_MSR_LSTAR, 49 IDX_MSR_CSTAR, 50 IDX_MSR_STAR, 51 IDX_MSR_SF_MASK, 52 HOST_MSR_NUM /* must be the last enumeration */ 53 }; 54 55 static uint64_t host_msrs[HOST_MSR_NUM]; 56 57 void 58 svm_msr_init(void) 59 { 60 /* 61 * It is safe to cache the values of the following MSRs because they 62 * don't change based on curcpu, curproc or curthread. 63 */ 64 host_msrs[IDX_MSR_LSTAR] = rdmsr(MSR_LSTAR); 65 host_msrs[IDX_MSR_CSTAR] = rdmsr(MSR_CSTAR); 66 host_msrs[IDX_MSR_STAR] = rdmsr(MSR_STAR); 67 host_msrs[IDX_MSR_SF_MASK] = rdmsr(MSR_SF_MASK); 68 } 69 70 void 71 svm_msr_guest_init(struct svm_softc *sc, int vcpu) 72 { 73 /* 74 * All the MSRs accessible to the guest are either saved/restored by 75 * hardware on every #VMEXIT/VMRUN (e.g., G_PAT) or are saved/restored 76 * by VMSAVE/VMLOAD (e.g., MSR_GSBASE). 77 * 78 * There are no guest MSRs that are saved/restored "by hand" so nothing 79 * more to do here. 80 */ 81 return; 82 } 83 84 void 85 svm_msr_guest_enter(struct svm_softc *sc, int vcpu) 86 { 87 /* 88 * Save host MSRs (if any) and restore guest MSRs (if any). 89 */ 90 } 91 92 void 93 svm_msr_guest_exit(struct svm_softc *sc, int vcpu) 94 { 95 /* 96 * Save guest MSRs (if any) and restore host MSRs. 97 */ 98 wrmsr(MSR_LSTAR, host_msrs[IDX_MSR_LSTAR]); 99 wrmsr(MSR_CSTAR, host_msrs[IDX_MSR_CSTAR]); 100 wrmsr(MSR_STAR, host_msrs[IDX_MSR_STAR]); 101 wrmsr(MSR_SF_MASK, host_msrs[IDX_MSR_SF_MASK]); 102 103 /* MSR_KGSBASE will be restored on the way back to userspace */ 104 } 105 106 int 107 svm_rdmsr(struct svm_softc *sc, int vcpu, u_int num, uint64_t *result, 108 bool *retu) 109 { 110 int error = 0; 111 112 switch (num) { 113 case MSR_MCG_CAP: 114 case MSR_MCG_STATUS: 115 *result = 0; 116 break; 117 case MSR_MTRRcap: 118 case MSR_MTRRdefType: 119 case MSR_MTRR4kBase ... MSR_MTRR4kBase + 8: 120 case MSR_MTRR16kBase ... MSR_MTRR16kBase + 1: 121 case MSR_MTRR64kBase: 122 case MSR_SYSCFG: 123 *result = 0; 124 break; 125 case MSR_AMDK8_IPM: 126 *result = 0; 127 break; 128 default: 129 error = EINVAL; 130 break; 131 } 132 133 return (error); 134 } 135 136 int 137 svm_wrmsr(struct svm_softc *sc, int vcpu, u_int num, uint64_t val, bool *retu) 138 { 139 int error = 0; 140 141 switch (num) { 142 case MSR_MCG_CAP: 143 case MSR_MCG_STATUS: 144 break; /* ignore writes */ 145 case MSR_MTRRcap: 146 vm_inject_gp(sc->vm, vcpu); 147 break; 148 case MSR_MTRRdefType: 149 case MSR_MTRR4kBase ... MSR_MTRR4kBase + 8: 150 case MSR_MTRR16kBase ... MSR_MTRR16kBase + 1: 151 case MSR_MTRR64kBase: 152 case MSR_SYSCFG: 153 break; /* Ignore writes */ 154 case MSR_AMDK8_IPM: 155 /* 156 * Ignore writes to the "Interrupt Pending Message" MSR. 157 */ 158 break; 159 case MSR_K8_UCODE_UPDATE: 160 /* 161 * Ignore writes to microcode update register. 162 */ 163 break; 164 default: 165 error = EINVAL; 166 break; 167 } 168 169 return (error); 170 } 171