#include <asm/debug.h>
#include <asm/dis.h>
#include <asm/ipl.h>
+#include <asm/unwind.h>
-/*
- * For dump_trace we have tree different stack to consider:
- * - the panic stack which is used if the kernel stack has overflown
- * - the asynchronous interrupt stack (cpu related)
- * - the synchronous kernel stack (process related)
- * The stack trace can start at any of the three stacks and can potentially
- * touch all of them. The order is: panic stack, async stack, sync stack.
- */
-static unsigned long __no_sanitize_address
-__dump_trace(dump_trace_func_t func, void *data, unsigned long sp,
- unsigned long low, unsigned long high)
+const char *stack_type_name(enum stack_type type)
{
- struct stack_frame *sf;
- struct pt_regs *regs;
-
- while (1) {
- if (sp < low || sp > high - sizeof(*sf))
- return sp;
- sf = (struct stack_frame *) sp;
- if (func(data, sf->gprs[8], 0))
- return sp;
- /* Follow the backchain. */
- while (1) {
- low = sp;
- sp = sf->back_chain;
- if (!sp)
- break;
- if (sp <= low || sp > high - sizeof(*sf))
- return sp;
- sf = (struct stack_frame *) sp;
- if (func(data, sf->gprs[8], 1))
- return sp;
- }
- /* Zero backchain detected, check for interrupt frame. */
- sp = (unsigned long) (sf + 1);
- if (sp <= low || sp > high - sizeof(*regs))
- return sp;
- regs = (struct pt_regs *) sp;
- if (!user_mode(regs)) {
- if (func(data, regs->psw.addr, 1))
- return sp;
- }
- low = sp;
- sp = regs->gprs[15];
+ switch (type) {
+ case STACK_TYPE_TASK:
+ return "task";
+ case STACK_TYPE_IRQ:
+ return "irq";
+ case STACK_TYPE_NODAT:
+ return "nodat";
+ case STACK_TYPE_RESTART:
+ return "restart";
+ default:
+ return "unknown";
}
}
-void dump_trace(dump_trace_func_t func, void *data, struct task_struct *task,
- unsigned long sp)
+static inline bool in_stack(unsigned long sp, struct stack_info *info,
+ enum stack_type type, unsigned long low,
+ unsigned long high)
+{
+ if (sp < low || sp >= high)
+ return false;
+ info->type = type;
+ info->begin = low;
+ info->end = high;
+ return true;
+}
+
+static bool in_task_stack(unsigned long sp, struct task_struct *task,
+ struct stack_info *info)
+{
+ unsigned long stack;
+
+ stack = (unsigned long) task_stack_page(task);
+ return in_stack(sp, info, STACK_TYPE_TASK, stack, stack + THREAD_SIZE);
+}
+
+static bool in_irq_stack(unsigned long sp, struct stack_info *info)
{
- unsigned long frame_size;
+ unsigned long frame_size, top;
frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
-#ifdef CONFIG_CHECK_STACK
- sp = __dump_trace(func, data, sp,
- S390_lowcore.nodat_stack + frame_size - THREAD_SIZE,
- S390_lowcore.nodat_stack + frame_size);
-#endif
- sp = __dump_trace(func, data, sp,
- S390_lowcore.async_stack + frame_size - THREAD_SIZE,
- S390_lowcore.async_stack + frame_size);
- task = task ?: current;
- __dump_trace(func, data, sp,
- (unsigned long)task_stack_page(task),
- (unsigned long)task_stack_page(task) + THREAD_SIZE);
+ top = S390_lowcore.async_stack + frame_size;
+ return in_stack(sp, info, STACK_TYPE_IRQ, top - THREAD_SIZE, top);
+}
+
+static bool in_nodat_stack(unsigned long sp, struct stack_info *info)
+{
+ unsigned long frame_size, top;
+
+ frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
+ top = S390_lowcore.nodat_stack + frame_size;
+ return in_stack(sp, info, STACK_TYPE_NODAT, top - THREAD_SIZE, top);
}
-EXPORT_SYMBOL_GPL(dump_trace);
-static int show_address(void *data, unsigned long address, int reliable)
+static bool in_restart_stack(unsigned long sp, struct stack_info *info)
{
- if (reliable)
- printk(" [<%016lx>] %pSR \n", address, (void *)address);
- else
- printk("([<%016lx>] %pSR)\n", address, (void *)address);
+ unsigned long frame_size, top;
+
+ frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
+ top = S390_lowcore.restart_stack + frame_size;
+ return in_stack(sp, info, STACK_TYPE_RESTART, top - THREAD_SIZE, top);
+}
+
+int get_stack_info(unsigned long sp, struct task_struct *task,
+ struct stack_info *info, unsigned long *visit_mask)
+{
+ if (!sp)
+ goto unknown;
+
+ task = task ? : current;
+
+ /* Check per-task stack */
+ if (in_task_stack(sp, task, info))
+ goto recursion_check;
+
+ if (task != current)
+ goto unknown;
+
+ /* Check per-cpu stacks */
+ if (!in_irq_stack(sp, info) &&
+ !in_nodat_stack(sp, info) &&
+ !in_restart_stack(sp, info))
+ goto unknown;
+
+recursion_check:
+ /*
+ * Make sure we don't iterate through any given stack more than once.
+ * If it comes up a second time then there's something wrong going on:
+ * just break out and report an unknown stack type.
+ */
+ if (*visit_mask & (1UL << info->type)) {
+ printk_deferred_once(KERN_WARNING
+ "WARNING: stack recursion on stack type %d\n",
+ info->type);
+ goto unknown;
+ }
+ *visit_mask |= 1UL << info->type;
return 0;
+unknown:
+ info->type = STACK_TYPE_UNKNOWN;
+ return -EINVAL;
}
void show_stack(struct task_struct *task, unsigned long *stack)
{
- unsigned long sp = (unsigned long) stack;
+ struct unwind_state state;
- if (!sp)
- sp = task ? task->thread.ksp : current_stack_pointer();
printk("Call Trace:\n");
- dump_trace(show_address, NULL, task, sp);
if (!task)
task = current;
- debug_show_held_locks(task);
+ unwind_for_each_frame(&state, task, NULL, (unsigned long) stack)
+ printk(state.reliable ? " [<%016lx>] %pSR \n" :
+ "([<%016lx>] %pSR)\n",
+ state.ip, (void *) state.ip);
+ debug_show_held_locks(task ? : current);
}
static void show_last_breaking_event(struct pt_regs *regs)
projects / linux-2.6-block.git / blobdiff