int try_stack_unwind(struct task_struct *task, struct pt_regs *regs,
unsigned long **stack, unsigned long *bp,
const struct stacktrace_ops *ops, void *data)
{
#ifdef CONFIG_STACK_UNWIND
int unw_ret = 0;
struct unwind_frame_info info;
if (call_trace < 0)
return 0;
if (regs) {
if (unwind_init_frame_info(&info, task, regs) == 0)
unw_ret = dump_trace_unwind(&info, ops, data);
} else if (task == current)
unw_ret = unwind_init_running(&info, dump_trace_unwind, ops, data);
#ifdef CONFIG_SMP
else if (task->on_cpu)
/* nothing */;
#endif
else if (unwind_init_blocked(&info, task) == 0)
unw_ret = dump_trace_unwind(&info, ops, data);
if (unw_ret > 0) {
if (call_trace == 1 && !arch_unw_user_mode(&info)) {
ops->warning_symbol(data, "DWARF2 unwinder stuck at %s\n",
UNW_PC(&info));
if (UNW_SP(&info) >= PAGE_OFFSET) {
ops->warning(data, "Leftover inexact backtrace:\n");
*stack = (void *)UNW_SP(&info);
*bp = UNW_FP(&info);
return 0;
}
} else if (call_trace >= 1)
return -1;
ops->warning(data, "Full inexact backtrace again:\n");
} else
ops->warning(data, "Inexact backtrace:\n");
#endif
return 0;
}
if (!__get_user(link, (unsigned long *)
(UNW_FP(frame) + FRAME_LINK_OFFSET))
#if FRAME_RETADDR_OFFSET < 0
&& link > bottom && link < UNW_FP(frame)
#else
&& link > UNW_FP(frame) && link < bottom
#endif
&& !(link & (sizeof(link) - 1))
&& !__get_user(UNW_PC(frame),
(unsigned long *)(UNW_FP(frame)
+ FRAME_RETADDR_OFFSET)))
{
UNW_SP(frame) =
UNW_FP(frame) + FRAME_RETADDR_OFFSET
#if FRAME_RETADDR_OFFSET < 0
-
#else
+
#endif
sizeof(UNW_PC(frame));
UNW_FP(frame) = link;
return 0;
}
