struct task_struct *kgdb_contthread;
int kgdb_single_step;
+pid_t kgdb_sstep_pid;
/* Our I/O buffers. */
static char remcom_in_buffer[BUFMAX];
if (err)
return err;
if (CACHE_FLUSH_IS_SAFE)
- flush_icache_range(addr, addr + length + 1);
+ flush_icache_range(addr, addr + length);
return 0;
}
*/
if (tid == 0 || tid == -1)
tid = -atomic_read(&kgdb_active) - 2;
- if (tid < 0) {
+ 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
/* Signal the primary CPU that we are done: */
atomic_set(&cpu_in_kgdb[cpu], 0);
+ touch_softlockup_watchdog();
clocksource_touch_watchdog();
local_irq_restore(flags);
}
static int kgdb_activate_sw_breakpoints(void)
{
unsigned long addr;
- int error = 0;
+ int error;
+ int ret = 0;
int i;
for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
addr = kgdb_break[i].bpt_addr;
error = kgdb_arch_set_breakpoint(addr,
kgdb_break[i].saved_instr);
- if (error)
- return error;
+ 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 0;
+ return ret;
}
static int kgdb_set_sw_break(unsigned long addr)
static int kgdb_deactivate_sw_breakpoints(void)
{
unsigned long addr;
- int error = 0;
+ int error;
+ int ret = 0;
int i;
for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
addr = kgdb_break[i].bpt_addr;
error = kgdb_arch_remove_breakpoint(addr,
kgdb_break[i].saved_instr);
- if (error)
- return error;
+ 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 0;
+ return ret;
}
static int kgdb_remove_sw_break(unsigned long addr)
/*
* All threads that don't have debuggerinfo should be
- * in __schedule() sleeping, since all other CPUs
+ * in schedule() sleeping, since all other CPUs
* are in kgdb_wait, and thus have debuggerinfo.
*/
if (local_debuggerinfo) {
return 1;
} else {
- error_packet(remcom_out_buffer, -EINVAL);
- return 0;
+ 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 */
struct kgdb_state kgdb_var;
struct kgdb_state *ks = &kgdb_var;
unsigned long flags;
+ int sstep_tries = 100;
int error = 0;
int i, cpu;
cpu_relax();
/*
- * Do not start the debugger connection on this CPU if the last
- * instance of the exception handler wanted to come into the
- * debugger on a different CPU via a single step
+ * 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 &&
- atomic_read(&kgdb_cpu_doing_single_step) != cpu) {
-
+ (kgdb_info[cpu].task &&
+ kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
atomic_set(&kgdb_active, -1);
+ touch_softlockup_watchdog();
clocksource_touch_watchdog();
local_irq_restore(flags);
* 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 || !kgdb_contthread) {
+ if (!kgdb_single_step) {
for (i = 0; i < NR_CPUS; i++)
atomic_set(&passive_cpu_wait[i], 1);
}
#ifdef CONFIG_SMP
/* Signal the other CPUs to enter kgdb_wait() */
- if ((!kgdb_single_step || !kgdb_contthread) && kgdb_do_roundup)
+ if ((!kgdb_single_step) && kgdb_do_roundup)
kgdb_roundup_cpus(flags);
#endif
kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
kgdb_deactivate_sw_breakpoints();
kgdb_single_step = 0;
- kgdb_contthread = NULL;
+ kgdb_contthread = current;
exception_level = 0;
/* Talk to debugger with gdbserial protocol */
kgdb_info[ks->cpu].task = NULL;
atomic_set(&cpu_in_kgdb[ks->cpu], 0);
- if (!kgdb_single_step || !kgdb_contthread) {
+ if (!kgdb_single_step) {
for (i = NR_CPUS-1; i >= 0; i--)
atomic_set(&passive_cpu_wait[i], 0);
/*
}
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;
+ }
/* Free kgdb_active */
atomic_set(&kgdb_active, -1);
+ touch_softlockup_watchdog();
clocksource_touch_watchdog();
local_irq_restore(flags);
static struct sysrq_key_op sysrq_gdb_op = {
.handler = sysrq_handle_gdb,
- .help_msg = "Gdb",
- .action_msg = "GDB",
+ .help_msg = "debug(G)",
+ .action_msg = "DEBUG",
};
#endif