2 * Stack dumping functions
4 * Copyright IBM Corp. 1999, 2013
7 #include <linux/kallsyms.h>
8 #include <linux/hardirq.h>
9 #include <linux/kprobes.h>
10 #include <linux/utsname.h>
11 #include <linux/export.h>
12 #include <linux/kdebug.h>
13 #include <linux/ptrace.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <asm/processor.h>
17 #include <asm/debug.h>
22 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
23 static int kstack_depth_to_print = 12;
24 #else /* CONFIG_64BIT */
25 #define LONG "%016lx "
26 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
27 static int kstack_depth_to_print = 20;
28 #endif /* CONFIG_64BIT */
31 * For show_trace we have tree different stack to consider:
32 * - the panic stack which is used if the kernel stack has overflown
33 * - the asynchronous interrupt stack (cpu related)
34 * - the synchronous kernel stack (process related)
35 * The stack trace can start at any of the three stack and can potentially
36 * touch all of them. The order is: panic stack, async stack, sync stack.
39 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
41 struct stack_frame *sf;
45 sp = sp & PSW_ADDR_INSN;
46 if (sp < low || sp > high - sizeof(*sf))
48 sf = (struct stack_frame *) sp;
49 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
50 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
51 /* Follow the backchain. */
54 sp = sf->back_chain & PSW_ADDR_INSN;
57 if (sp <= low || sp > high - sizeof(*sf))
59 sf = (struct stack_frame *) sp;
60 printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
61 print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
63 /* Zero backchain detected, check for interrupt frame. */
64 sp = (unsigned long) (sf + 1);
65 if (sp <= low || sp > high - sizeof(*regs))
67 regs = (struct pt_regs *) sp;
68 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
69 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
75 static void show_trace(struct task_struct *task, unsigned long *stack)
77 const unsigned long frame_size =
78 STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
79 register unsigned long __r15 asm ("15");
82 sp = (unsigned long) stack;
84 sp = task ? task->thread.ksp : __r15;
85 printk("Call Trace:\n");
86 #ifdef CONFIG_CHECK_STACK
88 S390_lowcore.panic_stack + frame_size - 4096,
89 S390_lowcore.panic_stack + frame_size);
92 S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
93 S390_lowcore.async_stack + frame_size);
95 __show_trace(sp, (unsigned long) task_stack_page(task),
96 (unsigned long) task_stack_page(task) + THREAD_SIZE);
98 __show_trace(sp, S390_lowcore.thread_info,
99 S390_lowcore.thread_info + THREAD_SIZE);
102 debug_show_held_locks(task);
105 void show_stack(struct task_struct *task, unsigned long *sp)
107 register unsigned long *__r15 asm ("15");
108 unsigned long *stack;
112 stack = task ? (unsigned long *) task->thread.ksp : __r15;
116 for (i = 0; i < kstack_depth_to_print; i++) {
117 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
119 if ((i * sizeof(long) % 32) == 0)
120 printk("%s ", i == 0 ? "" : "\n");
121 printk(LONG, *stack++);
124 show_trace(task, sp);
127 static void show_last_breaking_event(struct pt_regs *regs)
130 printk("Last Breaking-Event-Address:\n");
131 printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
132 print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
136 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
138 return (regs->psw.mask & bits) / ((~bits + 1) & bits);
141 void show_registers(struct pt_regs *regs)
145 mode = user_mode(regs) ? "User" : "Krnl";
146 printk("%s PSW : %p %p",
147 mode, (void *) regs->psw.mask,
148 (void *) regs->psw.addr);
149 print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
150 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
151 "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
152 mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
153 mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
154 mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
155 mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
156 mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
158 printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));
160 printk("\n%s GPRS: " FOURLONG, mode,
161 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
163 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
165 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
167 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
171 void show_regs(struct pt_regs *regs)
173 show_regs_print_info(KERN_DEFAULT);
174 show_registers(regs);
175 /* Show stack backtrace if pt_regs is from kernel mode */
176 if (!user_mode(regs))
177 show_trace(NULL, (unsigned long *) regs->gprs[15]);
178 show_last_breaking_event(regs);
181 static DEFINE_SPINLOCK(die_lock);
183 void die(struct pt_regs *regs, const char *str)
185 static int die_counter;
191 spin_lock_irq(&die_lock);
193 printk("%s: %04x [#%d] ", str, regs->int_code & 0xffff, ++die_counter);
194 #ifdef CONFIG_PREEMPT
200 #ifdef CONFIG_DEBUG_PAGEALLOC
201 printk("DEBUG_PAGEALLOC");
204 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
208 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
209 spin_unlock_irq(&die_lock);
211 panic("Fatal exception in interrupt");
213 panic("Fatal exception: panic_on_oops");