diff options
Diffstat (limited to 'kernel/kgdb.c')
| -rw-r--r-- | kernel/kgdb.c | 1764 |
1 files changed, 0 insertions, 1764 deletions
diff --git a/kernel/kgdb.c b/kernel/kgdb.c deleted file mode 100644 index 11f3515..0000000 --- a/kernel/kgdb.c +++ /dev/null @@ -1,1764 +0,0 @@ -/* - * KGDB stub. - * - * Maintainer: Jason Wessel <jason.wessel@windriver.com> - * - * Copyright (C) 2000-2001 VERITAS Software Corporation. - * Copyright (C) 2002-2004 Timesys Corporation - * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com> - * Copyright (C) 2004 Pavel Machek <pavel@suse.cz> - * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org> - * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd. - * Copyright (C) 2005-2008 Wind River Systems, Inc. - * Copyright (C) 2007 MontaVista Software, Inc. - * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> - * - * Contributors at various stages not listed above: - * Jason Wessel ( jason.wessel@windriver.com ) - * George Anzinger <george@mvista.com> - * Anurekh Saxena (anurekh.saxena@timesys.com) - * Lake Stevens Instrument Division (Glenn Engel) - * Jim Kingdon, Cygnus Support. - * - * Original KGDB stub: David Grothe <dave@gcom.com>, - * Tigran Aivazian <tigran@sco.com> - * - * This file is licensed under the terms of the GNU General Public License - * version 2. This program is licensed "as is" without any warranty of any - * kind, whether express or implied. - */ -#include <linux/pid_namespace.h> -#include <linux/clocksource.h> -#include <linux/interrupt.h> -#include <linux/spinlock.h> -#include <linux/console.h> -#include <linux/threads.h> -#include <linux/uaccess.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/ptrace.h> -#include <linux/reboot.h> -#include <linux/string.h> -#include <linux/delay.h> -#include <linux/sched.h> -#include <linux/sysrq.h> -#include <linux/init.h> -#include <linux/kgdb.h> -#include <linux/pid.h> -#include <linux/smp.h> -#include <linux/mm.h> - -#include <asm/cacheflush.h> -#include <asm/byteorder.h> -#include <asm/atomic.h> -#include <asm/system.h> -#include <asm/unaligned.h> - -static int kgdb_break_asap; - -#define KGDB_MAX_THREAD_QUERY 17 -struct kgdb_state { - int ex_vector; - int signo; - int err_code; - int cpu; - int pass_exception; - unsigned long thr_query; - unsigned long threadid; - long kgdb_usethreadid; - struct pt_regs *linux_regs; -}; - -/* Exception state values */ -#define DCPU_WANT_MASTER 0x1 /* Waiting to become a master kgdb cpu */ -#define DCPU_NEXT_MASTER 0x2 /* Transition from one master cpu to another */ -#define DCPU_IS_SLAVE 0x4 /* Slave cpu enter exception */ -#define DCPU_SSTEP 0x8 /* CPU is single stepping */ - -static struct debuggerinfo_struct { - void *debuggerinfo; - struct task_struct *task; - int exception_state; -} kgdb_info[NR_CPUS]; - -/** - * kgdb_connected - Is a host GDB connected to us? - */ -int kgdb_connected; -EXPORT_SYMBOL_GPL(kgdb_connected); - -/* All the KGDB handlers are installed */ -static int kgdb_io_module_registered; - -/* Guard for recursive entry */ -static int exception_level; - -static struct kgdb_io *kgdb_io_ops; -static DEFINE_SPINLOCK(kgdb_registration_lock); - -/* kgdb console driver is loaded */ -static int kgdb_con_registered; -/* determine if kgdb console output should be used */ -static int kgdb_use_con; - -static int __init opt_kgdb_con(char *str) -{ - kgdb_use_con = 1; - return 0; -} - -early_param("kgdbcon", opt_kgdb_con); - -module_param(kgdb_use_con, int, 0644); - -/* - * Holds information about breakpoints in a kernel. These breakpoints are - * added and removed by gdb. - */ -static struct kgdb_bkpt kgdb_break[KGDB_MAX_BREAKPOINTS] = { - [0 ... KGDB_MAX_BREAKPOINTS-1] = { .state = BP_UNDEFINED } -}; - -/* - * The CPU# of the active CPU, or -1 if none: - */ -atomic_t kgdb_active = ATOMIC_INIT(-1); - -/* - * We use NR_CPUs not PERCPU, in case kgdb is used to debug early - * bootup code (which might not have percpu set up yet): - */ -static atomic_t passive_cpu_wait[NR_CPUS]; -static atomic_t cpu_in_kgdb[NR_CPUS]; -atomic_t kgdb_setting_breakpoint; - -struct task_struct *kgdb_usethread; -struct task_struct *kgdb_contthread; - -int kgdb_single_step; -pid_t kgdb_sstep_pid; - -/* Our I/O buffers. */ -static char remcom_in_buffer[BUFMAX]; -static char remcom_out_buffer[BUFMAX]; - -/* Storage for the registers, in GDB format. */ -static unsigned long gdb_regs[(NUMREGBYTES + - sizeof(unsigned long) - 1) / - sizeof(unsigned long)]; - -/* to keep track of the CPU which is doing the single stepping*/ -atomic_t kgdb_cpu_doing_single_step = ATOMIC_INIT(-1); - -/* - * If you are debugging a problem where roundup (the collection of - * all other CPUs) is a problem [this should be extremely rare], - * then use the nokgdbroundup option to avoid roundup. In that case - * the other CPUs might interfere with your debugging context, so - * use this with care: - */ -static int kgdb_do_roundup = 1; - -static int __init opt_nokgdbroundup(char *str) -{ - kgdb_do_roundup = 0; - - return 0; -} - -early_param("nokgdbroundup", opt_nokgdbroundup); - -/* - * Finally, some KGDB code :-) - */ - -/* - * Weak aliases for breakpoint management, - * can be overriden by architectures when needed: - */ -int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr) -{ - int err; - - err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE); - if (err) - return err; - - return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr, - BREAK_INSTR_SIZE); -} - -int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle) -{ - return probe_kernel_write((char *)addr, - (char *)bundle, BREAK_INSTR_SIZE); -} - -int __weak kgdb_validate_break_address(unsigned long addr) -{ - char tmp_variable[BREAK_INSTR_SIZE]; - int err; - /* Validate setting the breakpoint and then removing it. In the - * remove fails, the kernel needs to emit a bad message because we - * are deep trouble not being able to put things back the way we - * found them. - */ - err = kgdb_arch_set_breakpoint(addr, tmp_variable); - if (err) - return err; - err = kgdb_arch_remove_breakpoint(addr, tmp_variable); - if (err) - printk(KERN_ERR "KGDB: Critical breakpoint error, kernel " - "memory destroyed at: %lx", addr); - return err; -} - -unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs) -{ - return instruction_pointer(regs); -} - -int __weak kgdb_arch_init(void) -{ - return 0; -} - -int __weak kgdb_skipexception(int exception, struct pt_regs *regs) -{ - return 0; -} - -void __weak -kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code) -{ - return; -} - -/** - * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb. - * @regs: Current &struct pt_regs. - * - * This function will be called if the particular architecture must - * disable hardware debugging while it is processing gdb packets or - * handling exception. - */ -void __weak kgdb_disable_hw_debug(struct pt_regs *regs) -{ -} - -/* - * GDB remote protocol parser: - */ - -static int hex(char ch) -{ - if ((ch >= 'a') && (ch <= 'f')) - return ch - 'a' + 10; - if ((ch >= '0') && (ch <= '9')) - return ch - '0'; - if ((ch >= 'A') && (ch <= 'F')) - return ch - 'A' + 10; - return -1; -} - -/* scan for the sequence $<data>#<checksum> */ -static void get_packet(char *buffer) -{ - unsigned char checksum; - unsigned char xmitcsum; - int count; - char ch; - - do { - /* - * Spin and wait around for the start character, ignore all - * other characters: - */ - while ((ch = (kgdb_io_ops->read_char())) != '$') - /* nothing */; - - kgdb_connected = 1; - checksum = 0; - xmitcsum = -1; - - count = 0; - - /* - * now, read until a # or end of buffer is found: - */ - while (count < (BUFMAX - 1)) { - ch = kgdb_io_ops->read_char(); - if (ch == '#') - break; - checksum = checksum + ch; - buffer[count] = ch; - count = count + 1; - } - buffer[count] = 0; - - if (ch == '#') { - xmitcsum = hex(kgdb_io_ops->read_char()) << 4; - xmitcsum += hex(kgdb_io_ops->read_char()); - - if (checksum != xmitcsum) - /* failed checksum */ - kgdb_io_ops->write_char('-'); - else - /* successful transfer */ - kgdb_io_ops->write_char('+'); - if (kgdb_io_ops->flush) - kgdb_io_ops->flush(); - } - } while (checksum != xmitcsum); -} - -/* - * Send the packet in buffer. - * Check for gdb connection if asked for. - */ -static void put_packet(char *buffer) -{ - unsigned char checksum; - int count; - char ch; - - /* - * $<packet info>#<checksum>. - */ - while (1) { - kgdb_io_ops->write_char('$'); - checksum = 0; - count = 0; - - while ((ch = buffer[count])) { - kgdb_io_ops->write_char(ch); - checksum += ch; - count++; - } - - kgdb_io_ops->write_char('#'); - kgdb_io_ops->write_char(hex_asc_hi(checksum)); - kgdb_io_ops->write_char(hex_asc_lo(checksum)); - if (kgdb_io_ops->flush) - kgdb_io_ops->flush(); - - /* Now see what we get in reply. */ - ch = kgdb_io_ops->read_char(); - - if (ch == 3) - ch = kgdb_io_ops->read_char(); - - /* If we get an ACK, we are done. */ - if (ch == '+') - return; - - /* - * If we get the start of another packet, this means - * that GDB is attempting to reconnect. We will NAK - * the packet being sent, and stop trying to send this - * packet. - */ - if (ch == '$') { - kgdb_io_ops->write_char('-'); - if (kgdb_io_ops->flush) - kgdb_io_ops->flush(); - return; - } - } -} - -/* - * Convert the memory pointed to by mem into hex, placing result in buf. - * Return a pointer to the last char put in buf (null). May return an error. - */ -int kgdb_mem2hex(char *mem, char *buf, int count) -{ - char *tmp; - int err; - - /* - * We use the upper half of buf as an intermediate buffer for the - * raw memory copy. Hex conversion will work against this one. - */ - tmp = buf + count; - - err = probe_kernel_read(tmp, mem, count); - if (!err) { - while (count > 0) { - buf = pack_hex_byte(buf, *tmp); - tmp++; - count--; - } - - *buf = 0; - } - - return err; -} - -/* - * Copy the binary array pointed to by buf into mem. Fix $, #, and - * 0x7d escaped with 0x7d. Return -EFAULT on failure or 0 on success. - * The input buf is overwitten with the result to write to mem. - */ -static int kgdb_ebin2mem(char *buf, char *mem, int count) -{ - int size = 0; - char *c = buf; - - while (count-- > 0) { - c[size] = *buf++; - if (c[size] == 0x7d) - c[size] = *buf++ ^ 0x20; - size++; - } - - return probe_kernel_write(mem, c, size); -} - -/* - * Convert the hex array pointed to by buf into binary to be placed in mem. - * Return a pointer to the character AFTER the last byte written. - * May return an error. - */ -int kgdb_hex2mem(char *buf, char *mem, int count) -{ - char *tmp_raw; - char *tmp_hex; - - /* - * We use the upper half of buf as an intermediate buffer for the - * raw memory that is converted from hex. - */ - tmp_raw = buf + count * 2; - - tmp_hex = tmp_raw - 1; - while (tmp_hex >= buf) { - tmp_raw--; - *tmp_raw = hex(*tmp_hex--); - *tmp_raw |= hex(*tmp_hex--) << 4; - } - - return probe_kernel_write(mem, tmp_raw, count); -} - -/* - * While we find nice hex chars, build a long_val. - * Return number of chars processed. - */ -int kgdb_hex2long(char **ptr, unsigned long *long_val) -{ - int hex_val; - int num = 0; - int negate = 0; - - *long_val = 0; - - if (**ptr == '-') { - negate = 1; - (*ptr)++; - } - while (**ptr) { - hex_val = hex(**ptr); - if (hex_val < 0) - break; - - *long_val = (*long_val << 4) | hex_val; - num++; - (*ptr)++; - } - - if (negate) - *long_val = -*long_val; - - return num; -} - -/* Write memory due to an 'M' or 'X' packet. */ -static int write_mem_msg(int binary) -{ - char *ptr = &remcom_in_buffer[1]; - unsigned long addr; - unsigned long length; - int err; - - if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' && - kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') { - if (binary) - err = kgdb_ebin2mem(ptr, (char *)addr, length); - else - err = kgdb_hex2mem(ptr, (char *)addr, length); - if (err) - return err; - if (CACHE_FLUSH_IS_SAFE) - flush_icache_range(addr, addr + length); - return 0; - } - - return -EINVAL; -} - -static void error_packet(char *pkt, int error) -{ - error = -error; - pkt[0] = 'E'; - pkt[1] = hex_asc[(error / 10)]; - pkt[2] = hex_asc[(error % 10)]; - pkt[3] = '\0'; -} - -/* - * Thread ID accessors. We represent a flat TID space to GDB, where - * the per CPU idle threads (which under Linux all have PID 0) are - * remapped to negative TIDs. - */ - -#define BUF_THREAD_ID_SIZE 16 - -static char *pack_threadid(char *pkt, unsigned char *id) -{ - char *limit; - - limit = pkt + BUF_THREAD_ID_SIZE; - while (pkt < limit) - pkt = pack_hex_byte(pkt, *id++); - - return pkt; -} - -static void int_to_threadref(unsigned char *id, int value) -{ - unsigned char *scan; - int i = 4; - - scan = (unsigned char *)id; - while (i--) - *scan++ = 0; - put_unaligned_be32(value, scan); -} - -static struct task_struct *getthread(struct pt_regs *regs, int tid) -{ - /* - * Non-positive TIDs are remapped to the cpu shadow information - */ - if (tid == 0 || tid == -1) - tid = -atomic_read(&kgdb_active) - 2; - if (tid < -1 && tid > -NR_CPUS - 2) { - if (kgdb_info[-tid - 2].task) - return kgdb_info[-tid - 2].task; - else - return idle_task(-tid - 2); - } - if (tid <= 0) { - printk(KERN_ERR "KGDB: Internal thread select error\n"); - dump_stack(); - return NULL; - } - - /* - * find_task_by_pid_ns() does not take the tasklist lock anymore - * but is nicely RCU locked - hence is a pretty resilient - * thing to use: - */ - return find_task_by_pid_ns(tid, &init_pid_ns); -} - -/* - * Some architectures need cache flushes when we set/clear a - * breakpoint: - */ -static void kgdb_flush_swbreak_addr(unsigned long addr) -{ - if (!CACHE_FLUSH_IS_SAFE) - return; - - if (current->mm && current->mm->mmap_cache) { - flush_cache_range(current->mm->mmap_cache, - addr, addr + BREAK_INSTR_SIZE); - } - /* Force flush instruction cache if it was outside the mm */ - flush_icache_range(addr, addr + BREAK_INSTR_SIZE); -} - -/* - * SW breakpoint management: - */ -static int kgdb_activate_sw_breakpoints(void) -{ - unsigned long addr; - int error; - int ret = 0; - int i; - - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if (kgdb_break[i].state != BP_SET) - continue; - - addr = kgdb_break[i].bpt_addr; - error = kgdb_arch_set_breakpoint(addr, - kgdb_break[i].saved_instr); - if (error) { - ret = error; - printk(KERN_INFO "KGDB: BP install failed: %lx", addr); - continue; - } - - kgdb_flush_swbreak_addr(addr); - kgdb_break[i].state = BP_ACTIVE; - } - return ret; -} - -static int kgdb_set_sw_break(unsigned long addr) -{ - int err = kgdb_validate_break_address(addr); - int breakno = -1; - int i; - - if (err) - return err; - - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if ((kgdb_break[i].state == BP_SET) && - (kgdb_break[i].bpt_addr == addr)) - return -EEXIST; - } - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if (kgdb_break[i].state == BP_REMOVED && - kgdb_break[i].bpt_addr == addr) { - breakno = i; - break; - } - } - - if (breakno == -1) { - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if (kgdb_break[i].state == BP_UNDEFINED) { - breakno = i; - break; - } - } - } - - if (breakno == -1) - return -E2BIG; - - kgdb_break[breakno].state = BP_SET; - kgdb_break[breakno].type = BP_BREAKPOINT; - kgdb_break[breakno].bpt_addr = addr; - - return 0; -} - -static int kgdb_deactivate_sw_breakpoints(void) -{ - unsigned long addr; - int error; - int ret = 0; - int i; - - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if (kgdb_break[i].state != BP_ACTIVE) - continue; - addr = kgdb_break[i].bpt_addr; - error = kgdb_arch_remove_breakpoint(addr, - kgdb_break[i].saved_instr); - if (error) { - printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr); - ret = error; - } - - kgdb_flush_swbreak_addr(addr); - kgdb_break[i].state = BP_SET; - } - return ret; -} - -static int kgdb_remove_sw_break(unsigned long addr) -{ - int i; - - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if ((kgdb_break[i].state == BP_SET) && - (kgdb_break[i].bpt_addr == addr)) { - kgdb_break[i].state = BP_REMOVED; - return 0; - } - } - return -ENOENT; -} - -int kgdb_isremovedbreak(unsigned long addr) -{ - int i; - - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if ((kgdb_break[i].state == BP_REMOVED) && - (kgdb_break[i].bpt_addr == addr)) - return 1; - } - return 0; -} - -static int remove_all_break(void) -{ - unsigned long addr; - int error; - int i; - - /* Clear memory breakpoints. */ - for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if (kgdb_break[i].state != BP_ACTIVE) - goto setundefined; - addr = kgdb_break[i].bpt_addr; - error = kgdb_arch_remove_breakpoint(addr, - kgdb_break[i].saved_instr); - if (error) - printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n", - addr); -setundefined: - kgdb_break[i].state = BP_UNDEFINED; - } - - /* Clear hardware breakpoints. */ - if (arch_kgdb_ops.remove_all_hw_break) - arch_kgdb_ops.remove_all_hw_break(); - - return 0; -} - -/* - * Remap normal tasks to their real PID, - * CPU shadow threads are mapped to -CPU - 2 - */ -static inline int shadow_pid(int realpid) -{ - if (realpid) - return realpid; - - return -raw_smp_processor_id() - 2; -} - -static char gdbmsgbuf[BUFMAX + 1]; - -static void kgdb_msg_write(const char *s, int len) -{ - char *bufptr; - int wcount; - int i; - - /* 'O'utput */ - gdbmsgbuf[0] = 'O'; - - /* Fill and send buffers... */ - while (len > 0) { - bufptr = gdbmsgbuf + 1; - - /* Calculate how many this time */ - if ((len << 1) > (BUFMAX - 2)) - wcount = (BUFMAX - 2) >> 1; - else - wcount = len; - - /* Pack in hex chars */ - for (i = 0; i < wcount; i++) - bufptr = pack_hex_byte(bufptr, s[i]); - *bufptr = '\0'; - - /* Move up */ - s += wcount; - len -= wcount; - - /* Write packet */ - put_packet(gdbmsgbuf); - } -} - -/* - * Return true if there is a valid kgdb I/O module. Also if no - * debugger is attached a message can be printed to the console about - * waiting for the debugger to attach. - * - * The print_wait argument is only to be true when called from inside - * the core kgdb_handle_exception, because it will wait for the - * debugger to attach. - */ -static int kgdb_io_ready(int print_wait) -{ - if (!kgdb_io_ops) - return 0; - if (kgdb_connected) - return 1; - if (atomic_read(&kgdb_setting_breakpoint)) - return 1; - if (print_wait) - printk(KERN_CRIT "KGDB: Waiting for remote debugger\n"); - return 1; -} - -/* - * All the functions that start with gdb_cmd are the various - * operations to implement the handlers for the gdbserial protocol - * where KGDB is communicating with an external debugger - */ - -/* Handle the '?' status packets */ -static void gdb_cmd_status(struct kgdb_state *ks) -{ - /* - * We know that this packet is only sent - * during initial connect. So to be safe, - * we clear out our breakpoints now in case - * GDB is reconnecting. - */ - remove_all_break(); - - remcom_out_buffer[0] = 'S'; - pack_hex_byte(&remcom_out_buffer[1], ks->signo); -} - -/* Handle the 'g' get registers request */ -static void gdb_cmd_getregs(struct kgdb_state *ks) -{ - struct task_struct *thread; - void *local_debuggerinfo; - int i; - - thread = kgdb_usethread; - if (!thread) { - thread = kgdb_info[ks->cpu].task; - local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo; - } else { - local_debuggerinfo = NULL; - for_each_online_cpu(i) { - /* - * Try to find the task on some other - * or possibly this node if we do not - * find the matching task then we try - * to approximate the results. - */ - if (thread == kgdb_info[i].task) - local_debuggerinfo = kgdb_info[i].debuggerinfo; - } - } - - /* - * All threads that don't have debuggerinfo should be - * in schedule() sleeping, since all other CPUs - * are in kgdb_wait, and thus have debuggerinfo. - */ - if (local_debuggerinfo) { - pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo); - } else { - /* - * Pull stuff saved during switch_to; nothing - * else is accessible (or even particularly - * relevant). - * - * This should be enough for a stack trace. - */ - sleeping_thread_to_gdb_regs(gdb_regs, thread); - } - kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES); -} - -/* Handle the 'G' set registers request */ -static void gdb_cmd_setregs(struct kgdb_state *ks) -{ - kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES); - - if (kgdb_usethread && kgdb_usethread != current) { - error_packet(remcom_out_buffer, -EINVAL); - } else { - gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs); - strcpy(remcom_out_buffer, "OK"); - } -} - -/* Handle the 'm' memory read bytes */ -static void gdb_cmd_memread(struct kgdb_state *ks) -{ - char *ptr = &remcom_in_buffer[1]; - unsigned long length; - unsigned long addr; - int err; - - if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' && - kgdb_hex2long(&ptr, &length) > 0) { - err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length); - if (err) - error_packet(remcom_out_buffer, err); - } else { - error_packet(remcom_out_buffer, -EINVAL); - } -} - -/* Handle the 'M' memory write bytes */ -static void gdb_cmd_memwrite(struct kgdb_state *ks) -{ - int err = write_mem_msg(0); - - if (err) - error_packet(remcom_out_buffer, err); - else - strcpy(remcom_out_buffer, "OK"); -} - -/* Handle the 'X' memory binary write bytes */ -static void gdb_cmd_binwrite(struct kgdb_state *ks) -{ - int err = write_mem_msg(1); - - if (err) - error_packet(remcom_out_buffer, err); - else - strcpy(remcom_out_buffer, "OK"); -} - -/* Handle the 'D' or 'k', detach or kill packets */ -static void gdb_cmd_detachkill(struct kgdb_state *ks) -{ - int error; - - /* The detach case */ - if (remcom_in_buffer[0] == 'D') { - error = remove_all_break(); - if (error < 0) { - error_packet(remcom_out_buffer, error); - } else { - strcpy(remcom_out_buffer, "OK"); - kgdb_connected = 0; - } - put_packet(remcom_out_buffer); - } else { - /* - * Assume the kill case, with no exit code checking, - * trying to force detach the debugger: - */ - remove_all_break(); - kgdb_connected = 0; - } -} - -/* Handle the 'R' reboot packets */ -static int gdb_cmd_reboot(struct kgdb_state *ks) -{ - /* For now, only honor R0 */ - if (strcmp(remcom_in_buffer, "R0") == 0) { - printk(KERN_CRIT "Executing emergency reboot\n"); - strcpy(remcom_out_buffer, "OK"); - put_packet(remcom_out_buffer); - - /* - * Execution should not return from - * machine_emergency_restart() - */ - machine_emergency_restart(); - kgdb_connected = 0; - - return 1; - } - return 0; -} - -/* Handle the 'q' query packets */ -static void gdb_cmd_query(struct kgdb_state *ks) -{ - struct task_struct *g; - struct task_struct *p; - unsigned char thref[8]; - char *ptr; - int i; - int cpu; - int finished = 0; - - switch (remcom_in_buffer[1]) { - case 's': - case 'f': - if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) { - error_packet(remcom_out_buffer, -EINVAL); - break; - } - - i = 0; - remcom_out_buffer[0] = 'm'; - ptr = remcom_out_buffer + 1; - if (remcom_in_buffer[1] == 'f') { - /* Each cpu is a shadow thread */ - for_each_online_cpu(cpu) { - ks->thr_query = 0; - int_to_threadref(thref, -cpu - 2); - pack_threadid(ptr, thref); - ptr += BUF_THREAD_ID_SIZE; - *(ptr++) = ','; - i++; - } - } - - do_each_thread(g, p) { - if (i >= ks->thr_query && !finished) { - int_to_threadref(thref, p->pid); - pack_threadid(ptr, thref); - ptr += BUF_THREAD_ID_SIZE; - *(ptr++) = ','; - ks->thr_query++; - if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0) - finished = 1; - } - i++; - } while_each_thread(g, p); - - *(--ptr) = '\0'; - break; - - case 'C': - /* Current thread id */ - strcpy(remcom_out_buffer, "QC"); - ks->threadid = shadow_pid(current->pid); - int_to_threadref(thref, ks->threadid); - pack_threadid(remcom_out_buffer + 2, thref); - break; - case 'T': - if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) { - error_packet(remcom_out_buffer, -EINVAL); - break; - } - ks->threadid = 0; - ptr = remcom_in_buffer + 17; - kgdb_hex2long(&ptr, &ks->threadid); - if (!getthread(ks->linux_regs, ks->threadid)) { - error_packet(remcom_out_buffer, -EINVAL); - break; - } - if ((int)ks->threadid > 0) { - kgdb_mem2hex(getthread(ks->linux_regs, - ks->threadid)->comm, - remcom_out_buffer, 16); - } else { - static char tmpstr[23 + BUF_THREAD_ID_SIZE]; - - sprintf(tmpstr, "shadowCPU%d", - (int)(-ks->threadid - 2)); - kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr)); - } - break; - } -} - -/* Handle the 'H' task query packets */ -static void gdb_cmd_task(struct kgdb_state *ks) -{ - struct task_struct *thread; - char *ptr; - - switch (remcom_in_buffer[1]) { - case 'g': - ptr = &remcom_in_buffer[2]; - kgdb_hex2long(&ptr, &ks->threadid); - thread = getthread(ks->linux_regs, ks->threadid); - if (!thread && ks->threadid > 0) { - error_packet(remcom_out_buffer, -EINVAL); - break; - } - kgdb_usethread = thread; - ks->kgdb_usethreadid = ks->threadid; - strcpy(remcom_out_buffer, "OK"); - break; - case 'c': - ptr = &remcom_in_buffer[2]; - kgdb_hex2long(&ptr, &ks->threadid); - if (!ks->threadid) { - kgdb_contthread = NULL; - } else { - thread = getthread(ks->linux_regs, ks->threadid); - if (!thread && ks->threadid > 0) { - error_packet(remcom_out_buffer, -EINVAL); - break; - } - kgdb_contthread = thread; - } - strcpy(remcom_out_buffer, "OK"); - break; - } -} - -/* Handle the 'T' thread query packets */ -static void gdb_cmd_thread(struct kgdb_state *ks) -{ - char *ptr = &remcom_in_buffer[1]; - struct task_struct *thread; - - kgdb_hex2long(&ptr, &ks->threadid); - thread = getthread(ks->linux_regs, ks->threadid); - if (thread) - strcpy(remcom_out_buffer, "OK"); - else - error_packet(remcom_out_buffer, -EINVAL); -} - -/* Handle the 'z' or 'Z' breakpoint remove or set packets */ -static void gdb_cmd_break(struct kgdb_state *ks) -{ - /* - * Since GDB-5.3, it's been drafted that '0' is a software - * breakpoint, '1' is a hardware breakpoint, so let's do that. - */ - char *bpt_type = &remcom_in_buffer[1]; - char *ptr = &remcom_in_buffer[2]; - unsigned long addr; - unsigned long length; - int error = 0; - - if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') { - /* Unsupported */ - if (*bpt_type > '4') - return; - } else { - if (*bpt_type != '0' && *bpt_type != '1') - /* Unsupported. */ - return; - } - - /* - * Test if this is a hardware breakpoint, and - * if we support it: - */ - if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT)) - /* Unsupported. */ - return; - - if (*(ptr++) != ',') { - error_packet(remcom_out_buffer, -EINVAL); - return; - } - if (!kgdb_hex2long(&ptr, &addr)) { - error_packet(remcom_out_buffer, -EINVAL); - return; - } - if (*(ptr++) != ',' || - !kgdb_hex2long(&ptr, &length)) { - error_packet(remcom_out_buffer, -EINVAL); - return; - } - - if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0') - error = kgdb_set_sw_break(addr); - else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0') - error = kgdb_remove_sw_break(addr); - else if (remcom_in_buffer[0] == 'Z') - error = arch_kgdb_ops.set_hw_breakpoint(addr, - (int)length, *bpt_type - '0'); - else if (remcom_in_buffer[0] == 'z') - error = arch_kgdb_ops.remove_hw_breakpoint(addr, - (int) length, *bpt_type - '0'); - - if (error == 0) - strcpy(remcom_out_buffer, "OK"); - else - error_packet(remcom_out_buffer, error); -} - -/* Handle the 'C' signal / exception passing packets */ -static int gdb_cmd_exception_pass(struct kgdb_state *ks) -{ - /* C09 == pass exception - * C15 == detach kgdb, pass exception - */ - if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') { - - ks->pass_exception = 1; - remcom_in_buffer[0] = 'c'; - - } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') { - - ks->pass_exception = 1; - remcom_in_buffer[0] = 'D'; - remove_all_break(); - kgdb_connected = 0; - return 1; - - } else { - kgdb_msg_write("KGDB only knows signal 9 (pass)" - " and 15 (pass and disconnect)\n" - "Executing a continue without signal passing\n", 0); - remcom_in_buffer[0] = 'c'; - } - - /* Indicate fall through */ - return -1; -} - -/* - * This function performs all gdbserial command procesing - */ -static int gdb_serial_stub(struct kgdb_state *ks) -{ - int error = 0; - int tmp; - - /* Clear the out buffer. */ - memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer)); - - if (kgdb_connected) { - unsigned char thref[8]; - char *ptr; - - /* Reply to host that an exception has occurred */ - ptr = remcom_out_buffer; - *ptr++ = 'T'; - ptr = pack_hex_byte(ptr, ks->signo); - ptr += strlen(strcpy(ptr, "thread:")); - int_to_threadref(thref, shadow_pid(current->pid)); - ptr = pack_threadid(ptr, thref); - *ptr++ = ';'; - put_packet(remcom_out_buffer); - } - - kgdb_usethread = kgdb_info[ks->cpu].task; - ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid); - ks->pass_exception = 0; - - while (1) { - error = 0; - - /* Clear the out buffer. */ - memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer)); - - get_packet(remcom_in_buffer); - - switch (remcom_in_buffer[0]) { - case '?': /* gdbserial status */ - gdb_cmd_status(ks); - break; - case 'g': /* return the value of the CPU registers */ - gdb_cmd_getregs(ks); - break; - case 'G': /* set the value of the CPU registers - return OK */ - gdb_cmd_setregs(ks); - break; - case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ - gdb_cmd_memread(ks); - break; - case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */ - gdb_cmd_memwrite(ks); - break; - case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */ - gdb_cmd_binwrite(ks); - break; - /* kill or detach. KGDB should treat this like a - * continue. - */ - case 'D': /* Debugger detach */ - case 'k': /* Debugger detach via kill */ - gdb_cmd_detachkill(ks); - goto default_handle; - case 'R': /* Reboot */ - if (gdb_cmd_reboot(ks)) - goto default_handle; - break; - case 'q': /* query command */ - gdb_cmd_query(ks); - break; - case 'H': /* task related */ - gdb_cmd_task(ks); - break; - case 'T': /* Query thread status */ - gdb_cmd_thread(ks); - break; - case 'z': /* Break point remove */ - case 'Z': /* Break point set */ - gdb_cmd_break(ks); - break; - case 'C': /* Exception passing */ - tmp = gdb_cmd_exception_pass(ks); - if (tmp > 0) - goto default_handle; - if (tmp == 0) - break; - /* Fall through on tmp < 0 */ - case 'c': /* Continue packet */ - case 's': /* Single step packet */ - if (kgdb_contthread && kgdb_contthread != current) { - /* Can't switch threads in kgdb */ - error_packet(remcom_out_buffer, -EINVAL); - break; - } - kgdb_activate_sw_breakpoints(); - /* Fall through to default processing */ - default: -default_handle: - error = kgdb_arch_handle_exception(ks->ex_vector, - ks->signo, - ks->err_code, - remcom_in_buffer, - remcom_out_buffer, - ks->linux_regs); - /* - * Leave cmd processing on error, detach, - * kill, continue, or single step. - */ - if (error >= 0 || remcom_in_buffer[0] == 'D' || - remcom_in_buffer[0] == 'k') { - error = 0; - goto kgdb_exit; - } - - } - - /* reply to the request */ - put_packet(remcom_out_buffer); - } - -kgdb_exit: - if (ks->pass_exception) - error = 1; - return error; -} - -static int kgdb_reenter_check(struct kgdb_state *ks) -{ - unsigned long addr; - - if (atomic_read(&kgdb_active) != raw_smp_processor_id()) - return 0; - - /* Panic on recursive debugger calls: */ - exception_level++; - addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs); - kgdb_deactivate_sw_breakpoints(); - - /* - * If the break point removed ok at the place exception - * occurred, try to recover and print a warning to the end - * user because the user planted a breakpoint in a place that - * KGDB needs in order to function. - */ - if (kgdb_remove_sw_break(addr) == 0) { - exception_level = 0; - kgdb_skipexception(ks->ex_vector, ks->linux_regs); - kgdb_activate_sw_breakpoints(); - printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n", - addr); - WARN_ON_ONCE(1); - - return 1; - } - remove_all_break(); - kgdb_skipexception(ks->ex_vector, ks->linux_regs); - - if (exception_level > 1) { - dump_stack(); - panic("Recursive entry to debugger"); - } - - printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n"); - dump_stack(); - panic("Recursive entry to debugger"); - - return 1; -} - -static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs) -{ - unsigned long flags; - int sstep_tries = 100; - int error = 0; - int i, cpu; - int trace_on = 0; -acquirelock: - /* - * Interrupts will be restored by the 'trap return' code, except when - * single stepping. - */ - local_irq_save(flags); - - cpu = ks->cpu; - kgdb_info[cpu].debuggerinfo = regs; - kgdb_info[cpu].task = current; - /* - * Make sure the above info reaches the primary CPU before - * our cpu_in_kgdb[] flag setting does: - */ - atomic_inc(&cpu_in_kgdb[cpu]); - - /* - * CPU will loop if it is a slave or request to become a kgdb - * master cpu and acquire the kgdb_active lock: - */ - while (1) { - if (kgdb_info[cpu].exception_state & DCPU_WANT_MASTER) { - if (atomic_cmpxchg(&kgdb_active, -1, cpu) == cpu) - break; - } else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) { - if (!atomic_read(&passive_cpu_wait[cpu])) - goto return_normal; - } else { -return_normal: - /* Return to normal operation by executing any - * hw breakpoint fixup. - */ - if (arch_kgdb_ops.correct_hw_break) - arch_kgdb_ops.correct_hw_break(); - if (trace_on) - tracing_on(); - atomic_dec(&cpu_in_kgdb[cpu]); - touch_softlockup_watchdog_sync(); - clocksource_touch_watchdog(); - local_irq_restore(flags); - return 0; - } - cpu_relax(); - } - - /* - * For single stepping, try to only enter on the processor - * that was single stepping. To gaurd against a deadlock, the - * kernel will only try for the value of sstep_tries before - * giving up and continuing on. - */ - if (atomic_read(&kgdb_cpu_doing_single_step) != -1 && - (kgdb_info[cpu].task && - kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) { - atomic_set(&kgdb_active, -1); - touch_softlockup_watchdog_sync(); - clocksource_touch_watchdog(); - local_irq_restore(flags); - - goto acquirelock; - } - - if (!kgdb_io_ready(1)) { - error = 1; - goto kgdb_restore; /* No I/O connection, so resume the system */ - } - - /* - * Don't enter if we have hit a removed breakpoint. - */ - if (kgdb_skipexception(ks->ex_vector, ks->linux_regs)) - goto kgdb_restore; - - /* Call the I/O driver's pre_exception routine */ - if (kgdb_io_ops->pre_exception) - kgdb_io_ops->pre_exception(); - - kgdb_disable_hw_debug(ks->linux_regs); - - /* - * Get the passive CPU lock which will hold all the non-primary - * CPU in a spin state while the debugger is active - */ - if (!kgdb_single_step) { - for (i = 0; i < NR_CPUS; i++) - atomic_inc(&passive_cpu_wait[i]); - } - -#ifdef CONFIG_SMP - /* Signal the other CPUs to enter kgdb_wait() */ - if ((!kgdb_single_step) && kgdb_do_roundup) - kgdb_roundup_cpus(flags); -#endif - - /* - * Wait for the other CPUs to be notified and be waiting for us: - */ - for_each_online_cpu(i) { - while (!atomic_read(&cpu_in_kgdb[i])) - cpu_relax(); - } - - /* - * At this point the primary processor is completely - * in the debugger and all secondary CPUs are quiescent - */ - kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code); - kgdb_deactivate_sw_breakpoints(); - kgdb_single_step = 0; - kgdb_contthread = current; - exception_level = 0; - trace_on = tracing_is_on(); - if (trace_on) - tracing_off(); - - /* Talk to debugger with gdbserial protocol */ - error = gdb_serial_stub(ks); - - /* Call the I/O driver's post_exception routine */ - if (kgdb_io_ops->post_exception) - kgdb_io_ops->post_exception(); - - atomic_dec(&cpu_in_kgdb[ks->cpu]); - - if (!kgdb_single_step) { - for (i = NR_CPUS-1; i >= 0; i--) - atomic_dec(&passive_cpu_wait[i]); - /* - * Wait till all the CPUs have quit - * from the debugger. - */ - for_each_online_cpu(i) { - while (atomic_read(&cpu_in_kgdb[i])) - cpu_relax(); - } - } - -kgdb_restore: - if (atomic_read(&kgdb_cpu_doing_single_step) != -1) { - int sstep_cpu = atomic_read(&kgdb_cpu_doing_single_step); - if (kgdb_info[sstep_cpu].task) - kgdb_sstep_pid = kgdb_info[sstep_cpu].task->pid; - else - kgdb_sstep_pid = 0; - } - if (trace_on) - tracing_on(); - /* Free kgdb_active */ - atomic_set(&kgdb_active, -1); - touch_softlockup_watchdog_sync(); - clocksource_touch_watchdog(); - local_irq_restore(flags); - - return error; -} - -/* - * kgdb_handle_exception() - main entry point from a kernel exception - * - * Locking hierarchy: - * interface locks, if any (begin_session) - * kgdb lock (kgdb_active) - */ -int -kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs) -{ - struct kgdb_state kgdb_var; - struct kgdb_state *ks = &kgdb_var; - int ret; - - ks->cpu = raw_smp_processor_id(); - ks->ex_vector = evector; - ks->signo = signo; - ks->ex_vector = evector; - ks->err_code = ecode; - ks->kgdb_usethreadid = 0; - ks->linux_regs = regs; - - if (kgdb_reenter_check(ks)) - return 0; /* Ouch, double exception ! */ - kgdb_info[ks->cpu].exception_state |= DCPU_WANT_MASTER; - ret = kgdb_cpu_enter(ks, regs); - kgdb_info[ks->cpu].exception_state &= ~DCPU_WANT_MASTER; - return ret; -} - -int kgdb_nmicallback(int cpu, void *regs) -{ -#ifdef CONFIG_SMP - struct kgdb_state kgdb_var; - struct kgdb_state *ks = &kgdb_var; - - memset(ks, 0, sizeof(struct kgdb_state)); - ks->cpu = cpu; - ks->linux_regs = regs; - - if (!atomic_read(&cpu_in_kgdb[cpu]) && - atomic_read(&kgdb_active) != -1 && - atomic_read(&kgdb_active) != cpu) { - kgdb_info[cpu].exception_state |= DCPU_IS_SLAVE; - kgdb_cpu_enter(ks, regs); - kgdb_info[cpu].exception_state &= ~DCPU_IS_SLAVE; - return 0; - } -#endif - return 1; -} - -static void kgdb_console_write(struct console *co, const char *s, - unsigned count) -{ - unsigned long flags; - - /* If we're debugging, or KGDB has not connected, don't try - * and print. */ - if (!kgdb_connected || atomic_read(&kgdb_active) != -1) - return; - - local_irq_save(flags); - kgdb_msg_write(s, count); - local_irq_restore(flags); -} - -static struct console kgdbcons = { - .name = "kgdb", - .write = kgdb_console_write, - .flags = CON_PRINTBUFFER | CON_ENABLED, - .index = -1, -}; - -#ifdef CONFIG_MAGIC_SYSRQ -static void sysrq_handle_gdb(int key, struct tty_struct *tty) -{ - if (!kgdb_io_ops) { - printk(KERN_CRIT "ERROR: No KGDB I/O module available\n"); - return; - } - if (!kgdb_connected) - printk(KERN_CRIT "Entering KGDB\n"); - - kgdb_breakpoint(); -} - -static struct sysrq_key_op sysrq_gdb_op = { - .handler = sysrq_handle_gdb, - .help_msg = "debug(G)", - .action_msg = "DEBUG", -}; -#endif - -static void kgdb_register_callbacks(void) -{ - if (!kgdb_io_module_registered) { - kgdb_io_module_registered = 1; - kgdb_arch_init(); -#ifdef CONFIG_MAGIC_SYSRQ - register_sysrq_key('g', &sysrq_gdb_op); -#endif - if (kgdb_use_con && !kgdb_con_registered) { - register_console(&kgdbcons); - kgdb_con_registered = 1; - } - } -} - -static void kgdb_unregister_callbacks(void) -{ - /* - * When this routine is called KGDB should unregister from the - * panic handler and clean up, making sure it is not handling any - * break exceptions at the time. - */ - if (kgdb_io_module_registered) { - kgdb_io_module_registered = 0; - kgdb_arch_exit(); -#ifdef CONFIG_MAGIC_SYSRQ - unregister_sysrq_key('g', &sysrq_gdb_op); -#endif - if (kgdb_con_registered) { - unregister_console(&kgdbcons); - kgdb_con_registered = 0; - } - } -} - -static void kgdb_initial_breakpoint(void) -{ - kgdb_break_asap = 0; - - printk(KERN_CRIT "kgdb: Waiting for connection from remote gdb...\n"); - kgdb_breakpoint(); -} - -/** - * kgdb_register_io_module - register KGDB IO module - * @new_kgdb_io_ops: the io ops vector - * - * Register it with the KGDB core. - */ -int kgdb_register_io_module(struct kgdb_io *new_kgdb_io_ops) -{ - int err; - - spin_lock(&kgdb_registration_lock); - - if (kgdb_io_ops) { - spin_unlock(&kgdb_registration_lock); - - printk(KERN_ERR "kgdb: Another I/O driver is already " - "registered with KGDB.\n"); - return -EBUSY; - } - - if (new_kgdb_io_ops->init) { - err = new_kgdb_io_ops->init(); - if (err) { - spin_unlock(&kgdb_registration_lock); - return err; - } - } - - kgdb_io_ops = new_kgdb_io_ops; - - spin_unlock(&kgdb_registration_lock); - - printk(KERN_INFO "kgdb: Registered I/O driver %s.\n", - new_kgdb_io_ops->name); - - /* Arm KGDB now. */ - kgdb_register_callbacks(); - - if (kgdb_break_asap) - kgdb_initial_breakpoint(); - - return 0; -} -EXPORT_SYMBOL_GPL(kgdb_register_io_module); - -/** - * kkgdb_unregister_io_module - unregister KGDB IO module - * @old_kgdb_io_ops: the io ops vector - * - * Unregister it with the KGDB core. - */ -void kgdb_unregister_io_module(struct kgdb_io *old_kgdb_io_ops) -{ - BUG_ON(kgdb_connected); - - /* - * KGDB is no longer able to communicate out, so - * unregister our callbacks and reset state. - */ - kgdb_unregister_callbacks(); - - spin_lock(&kgdb_registration_lock); - - WARN_ON_ONCE(kgdb_io_ops != old_kgdb_io_ops); - kgdb_io_ops = NULL; - - spin_unlock(&kgdb_registration_lock); - - printk(KERN_INFO - "kgdb: Unregistered I/O driver %s, debugger disabled.\n", - old_kgdb_io_ops->name); -} -EXPORT_SYMBOL_GPL(kgdb_unregister_io_module); - -/** - * kgdb_breakpoint - generate breakpoint exception - * - * This function will generate a breakpoint exception. It is used at the - * beginning of a program to sync up with a debugger and can be used - * otherwise as a quick means to stop program execution and "break" into - * the debugger. - */ -void kgdb_breakpoint(void) -{ - atomic_inc(&kgdb_setting_breakpoint); - wmb(); /* Sync point before breakpoint */ - arch_kgdb_breakpoint(); - wmb(); /* Sync point after breakpoint */ - atomic_dec(&kgdb_setting_breakpoint); -} -EXPORT_SYMBOL_GPL(kgdb_breakpoint); - -static int __init opt_kgdb_wait(char *str) -{ - kgdb_break_asap = 1; - - if (kgdb_io_module_registered) - kgdb_initial_breakpoint(); - - return 0; -} - -early_param("kgdbwait", opt_kgdb_wait); |
