1 /* 2 * Copyright (C) 2024, Simon Hamelin <simon.hamelin@grenoble-inp.org> 3 * 4 * Stop execution once a given address is reached or if the 5 * count of executed instructions reached a specified limit 6 * 7 * License: GNU GPL, version 2 or later. 8 * See the COPYING file in the top-level directory. 9 */ 10 11 #include <assert.h> 12 #include <glib.h> 13 #include <inttypes.h> 14 #include <stdio.h> 15 #include <stdlib.h> 16 17 #include <qemu-plugin.h> 18 19 QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; 20 21 /* Scoreboard to track executed instructions count */ 22 typedef struct { 23 uint64_t insn_count; 24 } InstructionsCount; 25 static struct qemu_plugin_scoreboard *insn_count_sb; 26 static qemu_plugin_u64 insn_count; 27 28 static uint64_t icount; 29 static int icount_exit_code; 30 31 static bool exit_on_icount; 32 static bool exit_on_address; 33 34 /* Map trigger addresses to exit code */ 35 static GHashTable *addrs_ht; 36 37 static void exit_emulation(int return_code, char *message) 38 { 39 qemu_plugin_outs(message); 40 g_free(message); 41 exit(return_code); 42 } 43 44 static void exit_icount_reached(unsigned int cpu_index, void *udata) 45 { 46 uint64_t insn_vaddr = GPOINTER_TO_UINT(udata); 47 char *msg = g_strdup_printf("icount reached at 0x%" PRIx64 ", exiting\n", 48 insn_vaddr); 49 50 exit_emulation(icount_exit_code, msg); 51 } 52 53 static void exit_address_reached(unsigned int cpu_index, void *udata) 54 { 55 uint64_t insn_vaddr = GPOINTER_TO_UINT(udata); 56 char *msg = g_strdup_printf("0x%" PRIx64 " reached, exiting\n", insn_vaddr); 57 int exit_code; 58 59 exit_code = GPOINTER_TO_INT( 60 g_hash_table_lookup(addrs_ht, GUINT_TO_POINTER(insn_vaddr))); 61 62 exit_emulation(exit_code, msg); 63 } 64 65 static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb) 66 { 67 size_t tb_n = qemu_plugin_tb_n_insns(tb); 68 for (size_t i = 0; i < tb_n; i++) { 69 struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i); 70 gpointer insn_vaddr = GUINT_TO_POINTER(qemu_plugin_insn_vaddr(insn)); 71 72 if (exit_on_icount) { 73 /* Increment and check scoreboard for each instruction */ 74 qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu( 75 insn, QEMU_PLUGIN_INLINE_ADD_U64, insn_count, 1); 76 qemu_plugin_register_vcpu_insn_exec_cond_cb( 77 insn, exit_icount_reached, QEMU_PLUGIN_CB_NO_REGS, 78 QEMU_PLUGIN_COND_EQ, insn_count, icount + 1, insn_vaddr); 79 } 80 81 if (exit_on_address) { 82 if (g_hash_table_contains(addrs_ht, insn_vaddr)) { 83 /* Exit triggered by address */ 84 qemu_plugin_register_vcpu_insn_exec_cb( 85 insn, exit_address_reached, QEMU_PLUGIN_CB_NO_REGS, 86 insn_vaddr); 87 } 88 } 89 } 90 } 91 92 static void plugin_exit(qemu_plugin_id_t id, void *p) 93 { 94 g_hash_table_destroy(addrs_ht); 95 qemu_plugin_scoreboard_free(insn_count_sb); 96 } 97 98 QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, 99 const qemu_info_t *info, int argc, 100 char **argv) 101 { 102 addrs_ht = g_hash_table_new(NULL, g_direct_equal); 103 104 insn_count_sb = qemu_plugin_scoreboard_new(sizeof(InstructionsCount)); 105 insn_count = qemu_plugin_scoreboard_u64_in_struct( 106 insn_count_sb, InstructionsCount, insn_count); 107 108 for (int i = 0; i < argc; i++) { 109 char *opt = argv[i]; 110 g_auto(GStrv) tokens = g_strsplit(opt, "=", 2); 111 if (g_strcmp0(tokens[0], "icount") == 0) { 112 g_auto(GStrv) icount_tokens = g_strsplit(tokens[1], ":", 2); 113 icount = g_ascii_strtoull(icount_tokens[0], NULL, 0); 114 if (icount < 1 || g_strrstr(icount_tokens[0], "-") != NULL) { 115 fprintf(stderr, 116 "icount parsing failed: '%s' must be a positive " 117 "integer\n", 118 icount_tokens[0]); 119 return -1; 120 } 121 if (icount_tokens[1]) { 122 icount_exit_code = g_ascii_strtoull(icount_tokens[1], NULL, 0); 123 } 124 exit_on_icount = true; 125 } else if (g_strcmp0(tokens[0], "addr") == 0) { 126 g_auto(GStrv) addr_tokens = g_strsplit(tokens[1], ":", 2); 127 uint64_t exit_addr = g_ascii_strtoull(addr_tokens[0], NULL, 0); 128 int exit_code = 0; 129 if (addr_tokens[1]) { 130 exit_code = g_ascii_strtoull(addr_tokens[1], NULL, 0); 131 } 132 g_hash_table_insert(addrs_ht, GUINT_TO_POINTER(exit_addr), 133 GINT_TO_POINTER(exit_code)); 134 exit_on_address = true; 135 } else { 136 fprintf(stderr, "option parsing failed: %s\n", opt); 137 return -1; 138 } 139 } 140 141 if (!exit_on_icount && !exit_on_address) { 142 fprintf(stderr, "'icount' or 'addr' argument missing\n"); 143 return -1; 144 } 145 146 /* Register translation block and exit callbacks */ 147 qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans); 148 qemu_plugin_register_atexit_cb(id, plugin_exit, NULL); 149 150 return 0; 151 } 152