diff options
Diffstat (limited to 'qemu/gdbstub.c')
-rw-r--r-- | qemu/gdbstub.c | 1769 |
1 files changed, 1769 insertions, 0 deletions
diff --git a/qemu/gdbstub.c b/qemu/gdbstub.c new file mode 100644 index 000000000..ffe7e6efb --- /dev/null +++ b/qemu/gdbstub.c @@ -0,0 +1,1769 @@ +/* + * gdb server stub + * + * Copyright (c) 2003-2005 Fabrice Bellard + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + */ +#include "config.h" +#include "qemu-common.h" +#ifdef CONFIG_USER_ONLY +#include <stdlib.h> +#include <stdio.h> +#include <stdarg.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <fcntl.h> + +#include "qemu.h" +#else +#include "monitor/monitor.h" +#include "sysemu/char.h" +#include "sysemu/sysemu.h" +#include "exec/gdbstub.h" +#endif + +#define MAX_PACKET_LENGTH 4096 + +#include "cpu.h" +#include "qemu/sockets.h" +#include "sysemu/kvm.h" +#include "exec/semihost.h" + +#ifdef CONFIG_USER_ONLY +#define GDB_ATTACHED "0" +#else +#define GDB_ATTACHED "1" +#endif + +static inline int target_memory_rw_debug(CPUState *cpu, target_ulong addr, + uint8_t *buf, int len, bool is_write) +{ + CPUClass *cc = CPU_GET_CLASS(cpu); + + if (cc->memory_rw_debug) { + return cc->memory_rw_debug(cpu, addr, buf, len, is_write); + } + return cpu_memory_rw_debug(cpu, addr, buf, len, is_write); +} + +enum { + GDB_SIGNAL_0 = 0, + GDB_SIGNAL_INT = 2, + GDB_SIGNAL_QUIT = 3, + GDB_SIGNAL_TRAP = 5, + GDB_SIGNAL_ABRT = 6, + GDB_SIGNAL_ALRM = 14, + GDB_SIGNAL_IO = 23, + GDB_SIGNAL_XCPU = 24, + GDB_SIGNAL_UNKNOWN = 143 +}; + +#ifdef CONFIG_USER_ONLY + +/* Map target signal numbers to GDB protocol signal numbers and vice + * versa. For user emulation's currently supported systems, we can + * assume most signals are defined. + */ + +static int gdb_signal_table[] = { + 0, + TARGET_SIGHUP, + TARGET_SIGINT, + TARGET_SIGQUIT, + TARGET_SIGILL, + TARGET_SIGTRAP, + TARGET_SIGABRT, + -1, /* SIGEMT */ + TARGET_SIGFPE, + TARGET_SIGKILL, + TARGET_SIGBUS, + TARGET_SIGSEGV, + TARGET_SIGSYS, + TARGET_SIGPIPE, + TARGET_SIGALRM, + TARGET_SIGTERM, + TARGET_SIGURG, + TARGET_SIGSTOP, + TARGET_SIGTSTP, + TARGET_SIGCONT, + TARGET_SIGCHLD, + TARGET_SIGTTIN, + TARGET_SIGTTOU, + TARGET_SIGIO, + TARGET_SIGXCPU, + TARGET_SIGXFSZ, + TARGET_SIGVTALRM, + TARGET_SIGPROF, + TARGET_SIGWINCH, + -1, /* SIGLOST */ + TARGET_SIGUSR1, + TARGET_SIGUSR2, +#ifdef TARGET_SIGPWR + TARGET_SIGPWR, +#else + -1, +#endif + -1, /* SIGPOLL */ + -1, + -1, + -1, + -1, + -1, + -1, + -1, + -1, + -1, + -1, + -1, +#ifdef __SIGRTMIN + __SIGRTMIN + 1, + __SIGRTMIN + 2, + __SIGRTMIN + 3, + __SIGRTMIN + 4, + __SIGRTMIN + 5, + __SIGRTMIN + 6, + __SIGRTMIN + 7, + __SIGRTMIN + 8, + __SIGRTMIN + 9, + __SIGRTMIN + 10, + __SIGRTMIN + 11, + __SIGRTMIN + 12, + __SIGRTMIN + 13, + __SIGRTMIN + 14, + __SIGRTMIN + 15, + __SIGRTMIN + 16, + __SIGRTMIN + 17, + __SIGRTMIN + 18, + __SIGRTMIN + 19, + __SIGRTMIN + 20, + __SIGRTMIN + 21, + __SIGRTMIN + 22, + __SIGRTMIN + 23, + __SIGRTMIN + 24, + __SIGRTMIN + 25, + __SIGRTMIN + 26, + __SIGRTMIN + 27, + __SIGRTMIN + 28, + __SIGRTMIN + 29, + __SIGRTMIN + 30, + __SIGRTMIN + 31, + -1, /* SIGCANCEL */ + __SIGRTMIN, + __SIGRTMIN + 32, + __SIGRTMIN + 33, + __SIGRTMIN + 34, + __SIGRTMIN + 35, + __SIGRTMIN + 36, + __SIGRTMIN + 37, + __SIGRTMIN + 38, + __SIGRTMIN + 39, + __SIGRTMIN + 40, + __SIGRTMIN + 41, + __SIGRTMIN + 42, + __SIGRTMIN + 43, + __SIGRTMIN + 44, + __SIGRTMIN + 45, + __SIGRTMIN + 46, + __SIGRTMIN + 47, + __SIGRTMIN + 48, + __SIGRTMIN + 49, + __SIGRTMIN + 50, + __SIGRTMIN + 51, + __SIGRTMIN + 52, + __SIGRTMIN + 53, + __SIGRTMIN + 54, + __SIGRTMIN + 55, + __SIGRTMIN + 56, + __SIGRTMIN + 57, + __SIGRTMIN + 58, + __SIGRTMIN + 59, + __SIGRTMIN + 60, + __SIGRTMIN + 61, + __SIGRTMIN + 62, + __SIGRTMIN + 63, + __SIGRTMIN + 64, + __SIGRTMIN + 65, + __SIGRTMIN + 66, + __SIGRTMIN + 67, + __SIGRTMIN + 68, + __SIGRTMIN + 69, + __SIGRTMIN + 70, + __SIGRTMIN + 71, + __SIGRTMIN + 72, + __SIGRTMIN + 73, + __SIGRTMIN + 74, + __SIGRTMIN + 75, + __SIGRTMIN + 76, + __SIGRTMIN + 77, + __SIGRTMIN + 78, + __SIGRTMIN + 79, + __SIGRTMIN + 80, + __SIGRTMIN + 81, + __SIGRTMIN + 82, + __SIGRTMIN + 83, + __SIGRTMIN + 84, + __SIGRTMIN + 85, + __SIGRTMIN + 86, + __SIGRTMIN + 87, + __SIGRTMIN + 88, + __SIGRTMIN + 89, + __SIGRTMIN + 90, + __SIGRTMIN + 91, + __SIGRTMIN + 92, + __SIGRTMIN + 93, + __SIGRTMIN + 94, + __SIGRTMIN + 95, + -1, /* SIGINFO */ + -1, /* UNKNOWN */ + -1, /* DEFAULT */ + -1, + -1, + -1, + -1, + -1, + -1 +#endif +}; +#else +/* In system mode we only need SIGINT and SIGTRAP; other signals + are not yet supported. */ + +enum { + TARGET_SIGINT = 2, + TARGET_SIGTRAP = 5 +}; + +static int gdb_signal_table[] = { + -1, + -1, + TARGET_SIGINT, + -1, + -1, + TARGET_SIGTRAP +}; +#endif + +#ifdef CONFIG_USER_ONLY +static int target_signal_to_gdb (int sig) +{ + int i; + for (i = 0; i < ARRAY_SIZE (gdb_signal_table); i++) + if (gdb_signal_table[i] == sig) + return i; + return GDB_SIGNAL_UNKNOWN; +} +#endif + +static int gdb_signal_to_target (int sig) +{ + if (sig < ARRAY_SIZE (gdb_signal_table)) + return gdb_signal_table[sig]; + else + return -1; +} + +//#define DEBUG_GDB + +typedef struct GDBRegisterState { + int base_reg; + int num_regs; + gdb_reg_cb get_reg; + gdb_reg_cb set_reg; + const char *xml; + struct GDBRegisterState *next; +} GDBRegisterState; + +enum RSState { + RS_INACTIVE, + RS_IDLE, + RS_GETLINE, + RS_CHKSUM1, + RS_CHKSUM2, +}; +typedef struct GDBState { + CPUState *c_cpu; /* current CPU for step/continue ops */ + CPUState *g_cpu; /* current CPU for other ops */ + CPUState *query_cpu; /* for q{f|s}ThreadInfo */ + enum RSState state; /* parsing state */ + char line_buf[MAX_PACKET_LENGTH]; + int line_buf_index; + int line_csum; + uint8_t last_packet[MAX_PACKET_LENGTH + 4]; + int last_packet_len; + int signal; +#ifdef CONFIG_USER_ONLY + int fd; + int running_state; +#else + CharDriverState *chr; + CharDriverState *mon_chr; +#endif + char syscall_buf[256]; + gdb_syscall_complete_cb current_syscall_cb; +} GDBState; + +/* By default use no IRQs and no timers while single stepping so as to + * make single stepping like an ICE HW step. + */ +static int sstep_flags = SSTEP_ENABLE|SSTEP_NOIRQ|SSTEP_NOTIMER; + +static GDBState *gdbserver_state; + +bool gdb_has_xml; + +#ifdef CONFIG_USER_ONLY +/* XXX: This is not thread safe. Do we care? */ +static int gdbserver_fd = -1; + +static int get_char(GDBState *s) +{ + uint8_t ch; + int ret; + + for(;;) { + ret = qemu_recv(s->fd, &ch, 1, 0); + if (ret < 0) { + if (errno == ECONNRESET) + s->fd = -1; + if (errno != EINTR && errno != EAGAIN) + return -1; + } else if (ret == 0) { + close(s->fd); + s->fd = -1; + return -1; + } else { + break; + } + } + return ch; +} +#endif + +static enum { + GDB_SYS_UNKNOWN, + GDB_SYS_ENABLED, + GDB_SYS_DISABLED, +} gdb_syscall_mode; + +/* Decide if either remote gdb syscalls or native file IO should be used. */ +int use_gdb_syscalls(void) +{ + SemihostingTarget target = semihosting_get_target(); + if (target == SEMIHOSTING_TARGET_NATIVE) { + /* -semihosting-config target=native */ + return false; + } else if (target == SEMIHOSTING_TARGET_GDB) { + /* -semihosting-config target=gdb */ + return true; + } + + /* -semihosting-config target=auto */ + /* On the first call check if gdb is connected and remember. */ + if (gdb_syscall_mode == GDB_SYS_UNKNOWN) { + gdb_syscall_mode = (gdbserver_state ? GDB_SYS_ENABLED + : GDB_SYS_DISABLED); + } + return gdb_syscall_mode == GDB_SYS_ENABLED; +} + +/* Resume execution. */ +static inline void gdb_continue(GDBState *s) +{ +#ifdef CONFIG_USER_ONLY + s->running_state = 1; +#else + if (!runstate_needs_reset()) { + vm_start(); + } +#endif +} + +static void put_buffer(GDBState *s, const uint8_t *buf, int len) +{ +#ifdef CONFIG_USER_ONLY + int ret; + + while (len > 0) { + ret = send(s->fd, buf, len, 0); + if (ret < 0) { + if (errno != EINTR && errno != EAGAIN) + return; + } else { + buf += ret; + len -= ret; + } + } +#else + qemu_chr_fe_write(s->chr, buf, len); +#endif +} + +static inline int fromhex(int v) +{ + if (v >= '0' && v <= '9') + return v - '0'; + else if (v >= 'A' && v <= 'F') + return v - 'A' + 10; + else if (v >= 'a' && v <= 'f') + return v - 'a' + 10; + else + return 0; +} + +static inline int tohex(int v) +{ + if (v < 10) + return v + '0'; + else + return v - 10 + 'a'; +} + +static void memtohex(char *buf, const uint8_t *mem, int len) +{ + int i, c; + char *q; + q = buf; + for(i = 0; i < len; i++) { + c = mem[i]; + *q++ = tohex(c >> 4); + *q++ = tohex(c & 0xf); + } + *q = '\0'; +} + +static void hextomem(uint8_t *mem, const char *buf, int len) +{ + int i; + + for(i = 0; i < len; i++) { + mem[i] = (fromhex(buf[0]) << 4) | fromhex(buf[1]); + buf += 2; + } +} + +/* return -1 if error, 0 if OK */ +static int put_packet_binary(GDBState *s, const char *buf, int len) +{ + int csum, i; + uint8_t *p; + + for(;;) { + p = s->last_packet; + *(p++) = '$'; + memcpy(p, buf, len); + p += len; + csum = 0; + for(i = 0; i < len; i++) { + csum += buf[i]; + } + *(p++) = '#'; + *(p++) = tohex((csum >> 4) & 0xf); + *(p++) = tohex((csum) & 0xf); + + s->last_packet_len = p - s->last_packet; + put_buffer(s, (uint8_t *)s->last_packet, s->last_packet_len); + +#ifdef CONFIG_USER_ONLY + i = get_char(s); + if (i < 0) + return -1; + if (i == '+') + break; +#else + break; +#endif + } + return 0; +} + +/* return -1 if error, 0 if OK */ +static int put_packet(GDBState *s, const char *buf) +{ +#ifdef DEBUG_GDB + printf("reply='%s'\n", buf); +#endif + + return put_packet_binary(s, buf, strlen(buf)); +} + +/* Encode data using the encoding for 'x' packets. */ +static int memtox(char *buf, const char *mem, int len) +{ + char *p = buf; + char c; + + while (len--) { + c = *(mem++); + switch (c) { + case '#': case '$': case '*': case '}': + *(p++) = '}'; + *(p++) = c ^ 0x20; + break; + default: + *(p++) = c; + break; + } + } + return p - buf; +} + +static const char *get_feature_xml(const char *p, const char **newp, + CPUClass *cc) +{ + size_t len; + int i; + const char *name; + static char target_xml[1024]; + + len = 0; + while (p[len] && p[len] != ':') + len++; + *newp = p + len; + + name = NULL; + if (strncmp(p, "target.xml", len) == 0) { + /* Generate the XML description for this CPU. */ + if (!target_xml[0]) { + GDBRegisterState *r; + CPUState *cpu = first_cpu; + + snprintf(target_xml, sizeof(target_xml), + "<?xml version=\"1.0\"?>" + "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">" + "<target>" + "<xi:include href=\"%s\"/>", + cc->gdb_core_xml_file); + + for (r = cpu->gdb_regs; r; r = r->next) { + pstrcat(target_xml, sizeof(target_xml), "<xi:include href=\""); + pstrcat(target_xml, sizeof(target_xml), r->xml); + pstrcat(target_xml, sizeof(target_xml), "\"/>"); + } + pstrcat(target_xml, sizeof(target_xml), "</target>"); + } + return target_xml; + } + for (i = 0; ; i++) { + name = xml_builtin[i][0]; + if (!name || (strncmp(name, p, len) == 0 && strlen(name) == len)) + break; + } + return name ? xml_builtin[i][1] : NULL; +} + +static int gdb_read_register(CPUState *cpu, uint8_t *mem_buf, int reg) +{ + CPUClass *cc = CPU_GET_CLASS(cpu); + CPUArchState *env = cpu->env_ptr; + GDBRegisterState *r; + + if (reg < cc->gdb_num_core_regs) { + return cc->gdb_read_register(cpu, mem_buf, reg); + } + + for (r = cpu->gdb_regs; r; r = r->next) { + if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) { + return r->get_reg(env, mem_buf, reg - r->base_reg); + } + } + return 0; +} + +static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg) +{ + CPUClass *cc = CPU_GET_CLASS(cpu); + CPUArchState *env = cpu->env_ptr; + GDBRegisterState *r; + + if (reg < cc->gdb_num_core_regs) { + return cc->gdb_write_register(cpu, mem_buf, reg); + } + + for (r = cpu->gdb_regs; r; r = r->next) { + if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) { + return r->set_reg(env, mem_buf, reg - r->base_reg); + } + } + return 0; +} + +/* Register a supplemental set of CPU registers. If g_pos is nonzero it + specifies the first register number and these registers are included in + a standard "g" packet. Direction is relative to gdb, i.e. get_reg is + gdb reading a CPU register, and set_reg is gdb modifying a CPU register. + */ + +void gdb_register_coprocessor(CPUState *cpu, + gdb_reg_cb get_reg, gdb_reg_cb set_reg, + int num_regs, const char *xml, int g_pos) +{ + GDBRegisterState *s; + GDBRegisterState **p; + + p = &cpu->gdb_regs; + while (*p) { + /* Check for duplicates. */ + if (strcmp((*p)->xml, xml) == 0) + return; + p = &(*p)->next; + } + + s = g_new0(GDBRegisterState, 1); + s->base_reg = cpu->gdb_num_regs; + s->num_regs = num_regs; + s->get_reg = get_reg; + s->set_reg = set_reg; + s->xml = xml; + + /* Add to end of list. */ + cpu->gdb_num_regs += num_regs; + *p = s; + if (g_pos) { + if (g_pos != s->base_reg) { + fprintf(stderr, "Error: Bad gdb register numbering for '%s'\n" + "Expected %d got %d\n", xml, g_pos, s->base_reg); + } else { + cpu->gdb_num_g_regs = cpu->gdb_num_regs; + } + } +} + +#ifndef CONFIG_USER_ONLY +/* Translate GDB watchpoint type to a flags value for cpu_watchpoint_* */ +static inline int xlat_gdb_type(CPUState *cpu, int gdbtype) +{ + static const int xlat[] = { + [GDB_WATCHPOINT_WRITE] = BP_GDB | BP_MEM_WRITE, + [GDB_WATCHPOINT_READ] = BP_GDB | BP_MEM_READ, + [GDB_WATCHPOINT_ACCESS] = BP_GDB | BP_MEM_ACCESS, + }; + + CPUClass *cc = CPU_GET_CLASS(cpu); + int cputype = xlat[gdbtype]; + + if (cc->gdb_stop_before_watchpoint) { + cputype |= BP_STOP_BEFORE_ACCESS; + } + return cputype; +} +#endif + +static int gdb_breakpoint_insert(target_ulong addr, target_ulong len, int type) +{ + CPUState *cpu; + int err = 0; + + if (kvm_enabled()) { + return kvm_insert_breakpoint(gdbserver_state->c_cpu, addr, len, type); + } + + switch (type) { + case GDB_BREAKPOINT_SW: + case GDB_BREAKPOINT_HW: + CPU_FOREACH(cpu) { + err = cpu_breakpoint_insert(cpu, addr, BP_GDB, NULL); + if (err) { + break; + } + } + return err; +#ifndef CONFIG_USER_ONLY + case GDB_WATCHPOINT_WRITE: + case GDB_WATCHPOINT_READ: + case GDB_WATCHPOINT_ACCESS: + CPU_FOREACH(cpu) { + err = cpu_watchpoint_insert(cpu, addr, len, + xlat_gdb_type(cpu, type), NULL); + if (err) { + break; + } + } + return err; +#endif + default: + return -ENOSYS; + } +} + +static int gdb_breakpoint_remove(target_ulong addr, target_ulong len, int type) +{ + CPUState *cpu; + int err = 0; + + if (kvm_enabled()) { + return kvm_remove_breakpoint(gdbserver_state->c_cpu, addr, len, type); + } + + switch (type) { + case GDB_BREAKPOINT_SW: + case GDB_BREAKPOINT_HW: + CPU_FOREACH(cpu) { + err = cpu_breakpoint_remove(cpu, addr, BP_GDB); + if (err) { + break; + } + } + return err; +#ifndef CONFIG_USER_ONLY + case GDB_WATCHPOINT_WRITE: + case GDB_WATCHPOINT_READ: + case GDB_WATCHPOINT_ACCESS: + CPU_FOREACH(cpu) { + err = cpu_watchpoint_remove(cpu, addr, len, + xlat_gdb_type(cpu, type)); + if (err) + break; + } + return err; +#endif + default: + return -ENOSYS; + } +} + +static void gdb_breakpoint_remove_all(void) +{ + CPUState *cpu; + + if (kvm_enabled()) { + kvm_remove_all_breakpoints(gdbserver_state->c_cpu); + return; + } + + CPU_FOREACH(cpu) { + cpu_breakpoint_remove_all(cpu, BP_GDB); +#ifndef CONFIG_USER_ONLY + cpu_watchpoint_remove_all(cpu, BP_GDB); +#endif + } +} + +static void gdb_set_cpu_pc(GDBState *s, target_ulong pc) +{ + CPUState *cpu = s->c_cpu; + + cpu_synchronize_state(cpu); + cpu_set_pc(cpu, pc); +} + +static CPUState *find_cpu(uint32_t thread_id) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + if (cpu_index(cpu) == thread_id) { + return cpu; + } + } + + return NULL; +} + +static int is_query_packet(const char *p, const char *query, char separator) +{ + unsigned int query_len = strlen(query); + + return strncmp(p, query, query_len) == 0 && + (p[query_len] == '\0' || p[query_len] == separator); +} + +static int gdb_handle_packet(GDBState *s, const char *line_buf) +{ + CPUState *cpu; + CPUClass *cc; + const char *p; + uint32_t thread; + int ch, reg_size, type, res; + char buf[MAX_PACKET_LENGTH]; + uint8_t mem_buf[MAX_PACKET_LENGTH]; + uint8_t *registers; + target_ulong addr, len; + +#ifdef DEBUG_GDB + printf("command='%s'\n", line_buf); +#endif + p = line_buf; + ch = *p++; + switch(ch) { + case '?': + /* TODO: Make this return the correct value for user-mode. */ + snprintf(buf, sizeof(buf), "T%02xthread:%02x;", GDB_SIGNAL_TRAP, + cpu_index(s->c_cpu)); + put_packet(s, buf); + /* Remove all the breakpoints when this query is issued, + * because gdb is doing and initial connect and the state + * should be cleaned up. + */ + gdb_breakpoint_remove_all(); + break; + case 'c': + if (*p != '\0') { + addr = strtoull(p, (char **)&p, 16); + gdb_set_cpu_pc(s, addr); + } + s->signal = 0; + gdb_continue(s); + return RS_IDLE; + case 'C': + s->signal = gdb_signal_to_target (strtoul(p, (char **)&p, 16)); + if (s->signal == -1) + s->signal = 0; + gdb_continue(s); + return RS_IDLE; + case 'v': + if (strncmp(p, "Cont", 4) == 0) { + int res_signal, res_thread; + + p += 4; + if (*p == '?') { + put_packet(s, "vCont;c;C;s;S"); + break; + } + res = 0; + res_signal = 0; + res_thread = 0; + while (*p) { + int action, signal; + + if (*p++ != ';') { + res = 0; + break; + } + action = *p++; + signal = 0; + if (action == 'C' || action == 'S') { + signal = gdb_signal_to_target(strtoul(p, (char **)&p, 16)); + if (signal == -1) { + signal = 0; + } + } else if (action != 'c' && action != 's') { + res = 0; + break; + } + thread = 0; + if (*p == ':') { + thread = strtoull(p+1, (char **)&p, 16); + } + action = tolower(action); + if (res == 0 || (res == 'c' && action == 's')) { + res = action; + res_signal = signal; + res_thread = thread; + } + } + if (res) { + if (res_thread != -1 && res_thread != 0) { + cpu = find_cpu(res_thread); + if (cpu == NULL) { + put_packet(s, "E22"); + break; + } + s->c_cpu = cpu; + } + if (res == 's') { + cpu_single_step(s->c_cpu, sstep_flags); + } + s->signal = res_signal; + gdb_continue(s); + return RS_IDLE; + } + break; + } else { + goto unknown_command; + } + case 'k': + /* Kill the target */ + fprintf(stderr, "\nQEMU: Terminated via GDBstub\n"); + exit(0); + case 'D': + /* Detach packet */ + gdb_breakpoint_remove_all(); + gdb_syscall_mode = GDB_SYS_DISABLED; + gdb_continue(s); + put_packet(s, "OK"); + break; + case 's': + if (*p != '\0') { + addr = strtoull(p, (char **)&p, 16); + gdb_set_cpu_pc(s, addr); + } + cpu_single_step(s->c_cpu, sstep_flags); + gdb_continue(s); + return RS_IDLE; + case 'F': + { + target_ulong ret; + target_ulong err; + + ret = strtoull(p, (char **)&p, 16); + if (*p == ',') { + p++; + err = strtoull(p, (char **)&p, 16); + } else { + err = 0; + } + if (*p == ',') + p++; + type = *p; + if (s->current_syscall_cb) { + s->current_syscall_cb(s->c_cpu, ret, err); + s->current_syscall_cb = NULL; + } + if (type == 'C') { + put_packet(s, "T02"); + } else { + gdb_continue(s); + } + } + break; + case 'g': + cpu_synchronize_state(s->g_cpu); + len = 0; + for (addr = 0; addr < s->g_cpu->gdb_num_g_regs; addr++) { + reg_size = gdb_read_register(s->g_cpu, mem_buf + len, addr); + len += reg_size; + } + memtohex(buf, mem_buf, len); + put_packet(s, buf); + break; + case 'G': + cpu_synchronize_state(s->g_cpu); + registers = mem_buf; + len = strlen(p) / 2; + hextomem((uint8_t *)registers, p, len); + for (addr = 0; addr < s->g_cpu->gdb_num_g_regs && len > 0; addr++) { + reg_size = gdb_write_register(s->g_cpu, registers, addr); + len -= reg_size; + registers += reg_size; + } + put_packet(s, "OK"); + break; + case 'm': + addr = strtoull(p, (char **)&p, 16); + if (*p == ',') + p++; + len = strtoull(p, NULL, 16); + if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len, false) != 0) { + put_packet (s, "E14"); + } else { + memtohex(buf, mem_buf, len); + put_packet(s, buf); + } + break; + case 'M': + addr = strtoull(p, (char **)&p, 16); + if (*p == ',') + p++; + len = strtoull(p, (char **)&p, 16); + if (*p == ':') + p++; + hextomem(mem_buf, p, len); + if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len, + true) != 0) { + put_packet(s, "E14"); + } else { + put_packet(s, "OK"); + } + break; + case 'p': + /* Older gdb are really dumb, and don't use 'g' if 'p' is avaialable. + This works, but can be very slow. Anything new enough to + understand XML also knows how to use this properly. */ + if (!gdb_has_xml) + goto unknown_command; + addr = strtoull(p, (char **)&p, 16); + reg_size = gdb_read_register(s->g_cpu, mem_buf, addr); + if (reg_size) { + memtohex(buf, mem_buf, reg_size); + put_packet(s, buf); + } else { + put_packet(s, "E14"); + } + break; + case 'P': + if (!gdb_has_xml) + goto unknown_command; + addr = strtoull(p, (char **)&p, 16); + if (*p == '=') + p++; + reg_size = strlen(p) / 2; + hextomem(mem_buf, p, reg_size); + gdb_write_register(s->g_cpu, mem_buf, addr); + put_packet(s, "OK"); + break; + case 'Z': + case 'z': + type = strtoul(p, (char **)&p, 16); + if (*p == ',') + p++; + addr = strtoull(p, (char **)&p, 16); + if (*p == ',') + p++; + len = strtoull(p, (char **)&p, 16); + if (ch == 'Z') + res = gdb_breakpoint_insert(addr, len, type); + else + res = gdb_breakpoint_remove(addr, len, type); + if (res >= 0) + put_packet(s, "OK"); + else if (res == -ENOSYS) + put_packet(s, ""); + else + put_packet(s, "E22"); + break; + case 'H': + type = *p++; + thread = strtoull(p, (char **)&p, 16); + if (thread == -1 || thread == 0) { + put_packet(s, "OK"); + break; + } + cpu = find_cpu(thread); + if (cpu == NULL) { + put_packet(s, "E22"); + break; + } + switch (type) { + case 'c': + s->c_cpu = cpu; + put_packet(s, "OK"); + break; + case 'g': + s->g_cpu = cpu; + put_packet(s, "OK"); + break; + default: + put_packet(s, "E22"); + break; + } + break; + case 'T': + thread = strtoull(p, (char **)&p, 16); + cpu = find_cpu(thread); + + if (cpu != NULL) { + put_packet(s, "OK"); + } else { + put_packet(s, "E22"); + } + break; + case 'q': + case 'Q': + /* parse any 'q' packets here */ + if (!strcmp(p,"qemu.sstepbits")) { + /* Query Breakpoint bit definitions */ + snprintf(buf, sizeof(buf), "ENABLE=%x,NOIRQ=%x,NOTIMER=%x", + SSTEP_ENABLE, + SSTEP_NOIRQ, + SSTEP_NOTIMER); + put_packet(s, buf); + break; + } else if (is_query_packet(p, "qemu.sstep", '=')) { + /* Display or change the sstep_flags */ + p += 10; + if (*p != '=') { + /* Display current setting */ + snprintf(buf, sizeof(buf), "0x%x", sstep_flags); + put_packet(s, buf); + break; + } + p++; + type = strtoul(p, (char **)&p, 16); + sstep_flags = type; + put_packet(s, "OK"); + break; + } else if (strcmp(p,"C") == 0) { + /* "Current thread" remains vague in the spec, so always return + * the first CPU (gdb returns the first thread). */ + put_packet(s, "QC1"); + break; + } else if (strcmp(p,"fThreadInfo") == 0) { + s->query_cpu = first_cpu; + goto report_cpuinfo; + } else if (strcmp(p,"sThreadInfo") == 0) { + report_cpuinfo: + if (s->query_cpu) { + snprintf(buf, sizeof(buf), "m%x", cpu_index(s->query_cpu)); + put_packet(s, buf); + s->query_cpu = CPU_NEXT(s->query_cpu); + } else + put_packet(s, "l"); + break; + } else if (strncmp(p,"ThreadExtraInfo,", 16) == 0) { + thread = strtoull(p+16, (char **)&p, 16); + cpu = find_cpu(thread); + if (cpu != NULL) { + cpu_synchronize_state(cpu); + len = snprintf((char *)mem_buf, sizeof(mem_buf), + "CPU#%d [%s]", cpu->cpu_index, + cpu->halted ? "halted " : "running"); + memtohex(buf, mem_buf, len); + put_packet(s, buf); + } + break; + } +#ifdef CONFIG_USER_ONLY + else if (strcmp(p, "Offsets") == 0) { + TaskState *ts = s->c_cpu->opaque; + + snprintf(buf, sizeof(buf), + "Text=" TARGET_ABI_FMT_lx ";Data=" TARGET_ABI_FMT_lx + ";Bss=" TARGET_ABI_FMT_lx, + ts->info->code_offset, + ts->info->data_offset, + ts->info->data_offset); + put_packet(s, buf); + break; + } +#else /* !CONFIG_USER_ONLY */ + else if (strncmp(p, "Rcmd,", 5) == 0) { + int len = strlen(p + 5); + + if ((len % 2) != 0) { + put_packet(s, "E01"); + break; + } + hextomem(mem_buf, p + 5, len); + len = len / 2; + mem_buf[len++] = 0; + qemu_chr_be_write(s->mon_chr, mem_buf, len); + put_packet(s, "OK"); + break; + } +#endif /* !CONFIG_USER_ONLY */ + if (is_query_packet(p, "Supported", ':')) { + snprintf(buf, sizeof(buf), "PacketSize=%x", MAX_PACKET_LENGTH); + cc = CPU_GET_CLASS(first_cpu); + if (cc->gdb_core_xml_file != NULL) { + pstrcat(buf, sizeof(buf), ";qXfer:features:read+"); + } + put_packet(s, buf); + break; + } + if (strncmp(p, "Xfer:features:read:", 19) == 0) { + const char *xml; + target_ulong total_len; + + cc = CPU_GET_CLASS(first_cpu); + if (cc->gdb_core_xml_file == NULL) { + goto unknown_command; + } + + gdb_has_xml = true; + p += 19; + xml = get_feature_xml(p, &p, cc); + if (!xml) { + snprintf(buf, sizeof(buf), "E00"); + put_packet(s, buf); + break; + } + + if (*p == ':') + p++; + addr = strtoul(p, (char **)&p, 16); + if (*p == ',') + p++; + len = strtoul(p, (char **)&p, 16); + + total_len = strlen(xml); + if (addr > total_len) { + snprintf(buf, sizeof(buf), "E00"); + put_packet(s, buf); + break; + } + if (len > (MAX_PACKET_LENGTH - 5) / 2) + len = (MAX_PACKET_LENGTH - 5) / 2; + if (len < total_len - addr) { + buf[0] = 'm'; + len = memtox(buf + 1, xml + addr, len); + } else { + buf[0] = 'l'; + len = memtox(buf + 1, xml + addr, total_len - addr); + } + put_packet_binary(s, buf, len + 1); + break; + } + if (is_query_packet(p, "Attached", ':')) { + put_packet(s, GDB_ATTACHED); + break; + } + /* Unrecognised 'q' command. */ + goto unknown_command; + + default: + unknown_command: + /* put empty packet */ + buf[0] = '\0'; + put_packet(s, buf); + break; + } + return RS_IDLE; +} + +void gdb_set_stop_cpu(CPUState *cpu) +{ + gdbserver_state->c_cpu = cpu; + gdbserver_state->g_cpu = cpu; +} + +#ifndef CONFIG_USER_ONLY +static void gdb_vm_state_change(void *opaque, int running, RunState state) +{ + GDBState *s = gdbserver_state; + CPUState *cpu = s->c_cpu; + char buf[256]; + const char *type; + int ret; + + if (running || s->state == RS_INACTIVE) { + return; + } + /* Is there a GDB syscall waiting to be sent? */ + if (s->current_syscall_cb) { + put_packet(s, s->syscall_buf); + return; + } + switch (state) { + case RUN_STATE_DEBUG: + if (cpu->watchpoint_hit) { + switch (cpu->watchpoint_hit->flags & BP_MEM_ACCESS) { + case BP_MEM_READ: + type = "r"; + break; + case BP_MEM_ACCESS: + type = "a"; + break; + default: + type = ""; + break; + } + snprintf(buf, sizeof(buf), + "T%02xthread:%02x;%swatch:" TARGET_FMT_lx ";", + GDB_SIGNAL_TRAP, cpu_index(cpu), type, + (target_ulong)cpu->watchpoint_hit->vaddr); + cpu->watchpoint_hit = NULL; + goto send_packet; + } + tb_flush(cpu); + ret = GDB_SIGNAL_TRAP; + break; + case RUN_STATE_PAUSED: + ret = GDB_SIGNAL_INT; + break; + case RUN_STATE_SHUTDOWN: + ret = GDB_SIGNAL_QUIT; + break; + case RUN_STATE_IO_ERROR: + ret = GDB_SIGNAL_IO; + break; + case RUN_STATE_WATCHDOG: + ret = GDB_SIGNAL_ALRM; + break; + case RUN_STATE_INTERNAL_ERROR: + ret = GDB_SIGNAL_ABRT; + break; + case RUN_STATE_SAVE_VM: + case RUN_STATE_RESTORE_VM: + return; + case RUN_STATE_FINISH_MIGRATE: + ret = GDB_SIGNAL_XCPU; + break; + default: + ret = GDB_SIGNAL_UNKNOWN; + break; + } + gdb_set_stop_cpu(cpu); + snprintf(buf, sizeof(buf), "T%02xthread:%02x;", ret, cpu_index(cpu)); + +send_packet: + put_packet(s, buf); + + /* disable single step if it was enabled */ + cpu_single_step(cpu, 0); +} +#endif + +/* Send a gdb syscall request. + This accepts limited printf-style format specifiers, specifically: + %x - target_ulong argument printed in hex. + %lx - 64-bit argument printed in hex. + %s - string pointer (target_ulong) and length (int) pair. */ +void gdb_do_syscall(gdb_syscall_complete_cb cb, const char *fmt, ...) +{ + va_list va; + char *p; + char *p_end; + target_ulong addr; + uint64_t i64; + GDBState *s; + + s = gdbserver_state; + if (!s) + return; + s->current_syscall_cb = cb; +#ifndef CONFIG_USER_ONLY + vm_stop(RUN_STATE_DEBUG); +#endif + va_start(va, fmt); + p = s->syscall_buf; + p_end = &s->syscall_buf[sizeof(s->syscall_buf)]; + *(p++) = 'F'; + while (*fmt) { + if (*fmt == '%') { + fmt++; + switch (*fmt++) { + case 'x': + addr = va_arg(va, target_ulong); + p += snprintf(p, p_end - p, TARGET_FMT_lx, addr); + break; + case 'l': + if (*(fmt++) != 'x') + goto bad_format; + i64 = va_arg(va, uint64_t); + p += snprintf(p, p_end - p, "%" PRIx64, i64); + break; + case 's': + addr = va_arg(va, target_ulong); + p += snprintf(p, p_end - p, TARGET_FMT_lx "/%x", + addr, va_arg(va, int)); + break; + default: + bad_format: + fprintf(stderr, "gdbstub: Bad syscall format string '%s'\n", + fmt - 1); + break; + } + } else { + *(p++) = *(fmt++); + } + } + *p = 0; + va_end(va); +#ifdef CONFIG_USER_ONLY + put_packet(s, s->syscall_buf); + gdb_handlesig(s->c_cpu, 0); +#else + /* In this case wait to send the syscall packet until notification that + the CPU has stopped. This must be done because if the packet is sent + now the reply from the syscall request could be received while the CPU + is still in the running state, which can cause packets to be dropped + and state transition 'T' packets to be sent while the syscall is still + being processed. */ + cpu_exit(s->c_cpu); +#endif +} + +static void gdb_read_byte(GDBState *s, int ch) +{ + int i, csum; + uint8_t reply; + +#ifndef CONFIG_USER_ONLY + if (s->last_packet_len) { + /* Waiting for a response to the last packet. If we see the start + of a new command then abandon the previous response. */ + if (ch == '-') { +#ifdef DEBUG_GDB + printf("Got NACK, retransmitting\n"); +#endif + put_buffer(s, (uint8_t *)s->last_packet, s->last_packet_len); + } +#ifdef DEBUG_GDB + else if (ch == '+') + printf("Got ACK\n"); + else + printf("Got '%c' when expecting ACK/NACK\n", ch); +#endif + if (ch == '+' || ch == '$') + s->last_packet_len = 0; + if (ch != '$') + return; + } + if (runstate_is_running()) { + /* when the CPU is running, we cannot do anything except stop + it when receiving a char */ + vm_stop(RUN_STATE_PAUSED); + } else +#endif + { + switch(s->state) { + case RS_IDLE: + if (ch == '$') { + s->line_buf_index = 0; + s->state = RS_GETLINE; + } + break; + case RS_GETLINE: + if (ch == '#') { + s->state = RS_CHKSUM1; + } else if (s->line_buf_index >= sizeof(s->line_buf) - 1) { + s->state = RS_IDLE; + } else { + s->line_buf[s->line_buf_index++] = ch; + } + break; + case RS_CHKSUM1: + s->line_buf[s->line_buf_index] = '\0'; + s->line_csum = fromhex(ch) << 4; + s->state = RS_CHKSUM2; + break; + case RS_CHKSUM2: + s->line_csum |= fromhex(ch); + csum = 0; + for(i = 0; i < s->line_buf_index; i++) { + csum += s->line_buf[i]; + } + if (s->line_csum != (csum & 0xff)) { + reply = '-'; + put_buffer(s, &reply, 1); + s->state = RS_IDLE; + } else { + reply = '+'; + put_buffer(s, &reply, 1); + s->state = gdb_handle_packet(s, s->line_buf); + } + break; + default: + abort(); + } + } +} + +/* Tell the remote gdb that the process has exited. */ +void gdb_exit(CPUArchState *env, int code) +{ + GDBState *s; + char buf[4]; + + s = gdbserver_state; + if (!s) { + return; + } +#ifdef CONFIG_USER_ONLY + if (gdbserver_fd < 0 || s->fd < 0) { + return; + } +#else + if (!s->chr) { + return; + } +#endif + + snprintf(buf, sizeof(buf), "W%02x", (uint8_t)code); + put_packet(s, buf); + +#ifndef CONFIG_USER_ONLY + qemu_chr_delete(s->chr); +#endif +} + +#ifdef CONFIG_USER_ONLY +int +gdb_queuesig (void) +{ + GDBState *s; + + s = gdbserver_state; + + if (gdbserver_fd < 0 || s->fd < 0) + return 0; + else + return 1; +} + +int +gdb_handlesig(CPUState *cpu, int sig) +{ + GDBState *s; + char buf[256]; + int n; + + s = gdbserver_state; + if (gdbserver_fd < 0 || s->fd < 0) { + return sig; + } + + /* disable single step if it was enabled */ + cpu_single_step(cpu, 0); + tb_flush(cpu); + + if (sig != 0) { + snprintf(buf, sizeof(buf), "S%02x", target_signal_to_gdb(sig)); + put_packet(s, buf); + } + /* put_packet() might have detected that the peer terminated the + connection. */ + if (s->fd < 0) { + return sig; + } + + sig = 0; + s->state = RS_IDLE; + s->running_state = 0; + while (s->running_state == 0) { + n = read(s->fd, buf, 256); + if (n > 0) { + int i; + + for (i = 0; i < n; i++) { + gdb_read_byte(s, buf[i]); + } + } else if (n == 0 || errno != EAGAIN) { + /* XXX: Connection closed. Should probably wait for another + connection before continuing. */ + return sig; + } + } + sig = s->signal; + s->signal = 0; + return sig; +} + +/* Tell the remote gdb that the process has exited due to SIG. */ +void gdb_signalled(CPUArchState *env, int sig) +{ + GDBState *s; + char buf[4]; + + s = gdbserver_state; + if (gdbserver_fd < 0 || s->fd < 0) { + return; + } + + snprintf(buf, sizeof(buf), "X%02x", target_signal_to_gdb(sig)); + put_packet(s, buf); +} + +static void gdb_accept(void) +{ + GDBState *s; + struct sockaddr_in sockaddr; + socklen_t len; + int fd; + + for(;;) { + len = sizeof(sockaddr); + fd = accept(gdbserver_fd, (struct sockaddr *)&sockaddr, &len); + if (fd < 0 && errno != EINTR) { + perror("accept"); + return; + } else if (fd >= 0) { +#ifndef _WIN32 + fcntl(fd, F_SETFD, FD_CLOEXEC); +#endif + break; + } + } + + /* set short latency */ + socket_set_nodelay(fd); + + s = g_malloc0(sizeof(GDBState)); + s->c_cpu = first_cpu; + s->g_cpu = first_cpu; + s->fd = fd; + gdb_has_xml = false; + + gdbserver_state = s; + + fcntl(fd, F_SETFL, O_NONBLOCK); +} + +static int gdbserver_open(int port) +{ + struct sockaddr_in sockaddr; + int fd, ret; + + fd = socket(PF_INET, SOCK_STREAM, 0); + if (fd < 0) { + perror("socket"); + return -1; + } +#ifndef _WIN32 + fcntl(fd, F_SETFD, FD_CLOEXEC); +#endif + + socket_set_fast_reuse(fd); + + sockaddr.sin_family = AF_INET; + sockaddr.sin_port = htons(port); + sockaddr.sin_addr.s_addr = 0; + ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr)); + if (ret < 0) { + perror("bind"); + close(fd); + return -1; + } + ret = listen(fd, 0); + if (ret < 0) { + perror("listen"); + close(fd); + return -1; + } + return fd; +} + +int gdbserver_start(int port) +{ + gdbserver_fd = gdbserver_open(port); + if (gdbserver_fd < 0) + return -1; + /* accept connections */ + gdb_accept(); + return 0; +} + +/* Disable gdb stub for child processes. */ +void gdbserver_fork(CPUState *cpu) +{ + GDBState *s = gdbserver_state; + + if (gdbserver_fd < 0 || s->fd < 0) { + return; + } + close(s->fd); + s->fd = -1; + cpu_breakpoint_remove_all(cpu, BP_GDB); + cpu_watchpoint_remove_all(cpu, BP_GDB); +} +#else +static int gdb_chr_can_receive(void *opaque) +{ + /* We can handle an arbitrarily large amount of data. + Pick the maximum packet size, which is as good as anything. */ + return MAX_PACKET_LENGTH; +} + +static void gdb_chr_receive(void *opaque, const uint8_t *buf, int size) +{ + int i; + + for (i = 0; i < size; i++) { + gdb_read_byte(gdbserver_state, buf[i]); + } +} + +static void gdb_chr_event(void *opaque, int event) +{ + switch (event) { + case CHR_EVENT_OPENED: + vm_stop(RUN_STATE_PAUSED); + gdb_has_xml = false; + break; + default: + break; + } +} + +static void gdb_monitor_output(GDBState *s, const char *msg, int len) +{ + char buf[MAX_PACKET_LENGTH]; + + buf[0] = 'O'; + if (len > (MAX_PACKET_LENGTH/2) - 1) + len = (MAX_PACKET_LENGTH/2) - 1; + memtohex(buf + 1, (uint8_t *)msg, len); + put_packet(s, buf); +} + +static int gdb_monitor_write(CharDriverState *chr, const uint8_t *buf, int len) +{ + const char *p = (const char *)buf; + int max_sz; + + max_sz = (sizeof(gdbserver_state->last_packet) - 2) / 2; + for (;;) { + if (len <= max_sz) { + gdb_monitor_output(gdbserver_state, p, len); + break; + } + gdb_monitor_output(gdbserver_state, p, max_sz); + p += max_sz; + len -= max_sz; + } + return len; +} + +#ifndef _WIN32 +static void gdb_sigterm_handler(int signal) +{ + if (runstate_is_running()) { + vm_stop(RUN_STATE_PAUSED); + } +} +#endif + +int gdbserver_start(const char *device) +{ + GDBState *s; + char gdbstub_device_name[128]; + CharDriverState *chr = NULL; + CharDriverState *mon_chr; + + if (!device) + return -1; + if (strcmp(device, "none") != 0) { + if (strstart(device, "tcp:", NULL)) { + /* enforce required TCP attributes */ + snprintf(gdbstub_device_name, sizeof(gdbstub_device_name), + "%s,nowait,nodelay,server", device); + device = gdbstub_device_name; + } +#ifndef _WIN32 + else if (strcmp(device, "stdio") == 0) { + struct sigaction act; + + memset(&act, 0, sizeof(act)); + act.sa_handler = gdb_sigterm_handler; + sigaction(SIGINT, &act, NULL); + } +#endif + chr = qemu_chr_new("gdb", device, NULL); + if (!chr) + return -1; + + qemu_chr_fe_claim_no_fail(chr); + qemu_chr_add_handlers(chr, gdb_chr_can_receive, gdb_chr_receive, + gdb_chr_event, NULL); + } + + s = gdbserver_state; + if (!s) { + s = g_malloc0(sizeof(GDBState)); + gdbserver_state = s; + + qemu_add_vm_change_state_handler(gdb_vm_state_change, NULL); + + /* Initialize a monitor terminal for gdb */ + mon_chr = qemu_chr_alloc(); + mon_chr->chr_write = gdb_monitor_write; + monitor_init(mon_chr, 0); + } else { + if (s->chr) + qemu_chr_delete(s->chr); + mon_chr = s->mon_chr; + memset(s, 0, sizeof(GDBState)); + } + s->c_cpu = first_cpu; + s->g_cpu = first_cpu; + s->chr = chr; + s->state = chr ? RS_IDLE : RS_INACTIVE; + s->mon_chr = mon_chr; + s->current_syscall_cb = NULL; + + return 0; +} +#endif |