1 // SPDX-License-Identifier: GPL-2.0 2 3 #include "misc.h" 4 #include "sev.h" 5 6 #include <linux/kernel.h> 7 #include <linux/string.h> 8 #include <asm/insn.h> 9 #include <asm/pgtable_types.h> 10 #include <asm/ptrace.h> 11 #include <asm/sev.h> 12 #include <asm/trapnr.h> 13 #include <asm/trap_pf.h> 14 #include <asm/fpu/xcr.h> 15 16 #define __BOOT_COMPRESSED 17 18 /* Basic instruction decoding support needed */ 19 #include "../../lib/inat.c" 20 #include "../../lib/insn.c" 21 22 /* 23 * Copy a version of this function here - insn-eval.c can't be used in 24 * pre-decompression code. 25 */ 26 bool insn_has_rep_prefix(struct insn *insn) 27 { 28 insn_byte_t p; 29 int i; 30 31 insn_get_prefixes(insn); 32 33 for_each_insn_prefix(insn, i, p) { 34 if (p == 0xf2 || p == 0xf3) 35 return true; 36 } 37 38 return false; 39 } 40 41 enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) 42 { 43 char buffer[MAX_INSN_SIZE]; 44 int ret; 45 46 memcpy(buffer, (unsigned char *)ctxt->regs->ip, MAX_INSN_SIZE); 47 48 ret = insn_decode(&ctxt->insn, buffer, MAX_INSN_SIZE, INSN_MODE_64); 49 if (ret < 0) 50 return ES_DECODE_FAILED; 51 52 return ES_OK; 53 } 54 55 extern void sev_insn_decode_init(void) __alias(inat_init_tables); 56 57 /* 58 * Only a dummy for insn_get_seg_base() - Early boot-code is 64bit only and 59 * doesn't use segments. 60 */ 61 static unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx) 62 { 63 return 0UL; 64 } 65 66 static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, 67 void *dst, char *buf, size_t size) 68 { 69 memcpy(dst, buf, size); 70 71 return ES_OK; 72 } 73 74 static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, 75 void *src, char *buf, size_t size) 76 { 77 memcpy(buf, src, size); 78 79 return ES_OK; 80 } 81 82 static enum es_result vc_ioio_check(struct es_em_ctxt *ctxt, u16 port, size_t size) 83 { 84 return ES_OK; 85 } 86 87 static bool fault_in_kernel_space(unsigned long address) 88 { 89 return false; 90 } 91 92 #define sev_printk(fmt, ...) 93 94 #include "../../coco/sev/vc-shared.c" 95 96 void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) 97 { 98 struct es_em_ctxt ctxt; 99 enum es_result result; 100 101 if (!boot_ghcb && !early_setup_ghcb()) 102 sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SEV_ES_GEN_REQ); 103 104 vc_ghcb_invalidate(boot_ghcb); 105 result = vc_init_em_ctxt(&ctxt, regs, exit_code); 106 if (result != ES_OK) 107 goto finish; 108 109 result = vc_check_opcode_bytes(&ctxt, exit_code); 110 if (result != ES_OK) 111 goto finish; 112 113 switch (exit_code) { 114 case SVM_EXIT_RDTSC: 115 case SVM_EXIT_RDTSCP: 116 result = vc_handle_rdtsc(boot_ghcb, &ctxt, exit_code); 117 break; 118 case SVM_EXIT_IOIO: 119 result = vc_handle_ioio(boot_ghcb, &ctxt); 120 break; 121 case SVM_EXIT_CPUID: 122 result = vc_handle_cpuid(boot_ghcb, &ctxt); 123 break; 124 default: 125 result = ES_UNSUPPORTED; 126 break; 127 } 128 129 finish: 130 if (result == ES_OK) 131 vc_finish_insn(&ctxt); 132 else if (result != ES_RETRY) 133 sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SEV_ES_GEN_REQ); 134 } 135