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>
23 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
24 static int kstack_depth_to_print = 12;
25 #else /* CONFIG_64BIT */
26 #define LONG "%016lx "
27 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
28 static int kstack_depth_to_print = 20;
29 #endif /* CONFIG_64BIT */
32 * For show_trace we have tree different stack to consider:
33 * - the panic stack which is used if the kernel stack has overflown
34 * - the asynchronous interrupt stack (cpu related)
35 * - the synchronous kernel stack (process related)
36 * The stack trace can start at any of the three stack and can potentially
37 * touch all of them. The order is: panic stack, async stack, sync stack.
40 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
42 struct stack_frame *sf;
47 sp = sp & PSW_ADDR_INSN;
48 if (sp < low || sp > high - sizeof(*sf))
50 sf = (struct stack_frame *) sp;
51 addr = sf->gprs[8] & PSW_ADDR_INSN;
52 printk("([<%016lx>] %pSR)\n", addr, (void *)addr);
53 /* Follow the backchain. */
56 sp = sf->back_chain & PSW_ADDR_INSN;
59 if (sp <= low || sp > high - sizeof(*sf))
61 sf = (struct stack_frame *) sp;
62 addr = sf->gprs[8] & PSW_ADDR_INSN;
63 printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
65 /* Zero backchain detected, check for interrupt frame. */
66 sp = (unsigned long) (sf + 1);
67 if (sp <= low || sp > high - sizeof(*regs))
69 regs = (struct pt_regs *) sp;
70 addr = regs->psw.addr & PSW_ADDR_INSN;
71 printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
77 static void show_trace(struct task_struct *task, unsigned long *stack)
79 const unsigned long frame_size =
80 STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
81 register unsigned long __r15 asm ("15");
84 sp = (unsigned long) stack;
86 sp = task ? task->thread.ksp : __r15;
87 printk("Call Trace:\n");
88 #ifdef CONFIG_CHECK_STACK
90 S390_lowcore.panic_stack + frame_size - 4096,
91 S390_lowcore.panic_stack + frame_size);
94 S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
95 S390_lowcore.async_stack + frame_size);
97 __show_trace(sp, (unsigned long) task_stack_page(task),
98 (unsigned long) task_stack_page(task) + THREAD_SIZE);
100 __show_trace(sp, S390_lowcore.thread_info,
101 S390_lowcore.thread_info + THREAD_SIZE);
104 debug_show_held_locks(task);
107 void show_stack(struct task_struct *task, unsigned long *sp)
109 register unsigned long *__r15 asm ("15");
110 unsigned long *stack;
114 stack = task ? (unsigned long *) task->thread.ksp : __r15;
118 for (i = 0; i < kstack_depth_to_print; i++) {
119 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
121 if ((i * sizeof(long) % 32) == 0)
122 printk("%s ", i == 0 ? "" : "\n");
123 printk(LONG, *stack++);
126 show_trace(task, sp);
129 static void show_last_breaking_event(struct pt_regs *regs)
132 printk("Last Breaking-Event-Address:\n");
133 printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
137 static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
139 return (regs->psw.mask & bits) / ((~bits + 1) & bits);
142 void show_registers(struct pt_regs *regs)
146 mode = user_mode(regs) ? "User" : "Krnl";
147 printk("%s PSW : %p %p", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
148 if (!user_mode(regs))
149 printk(" (%pSR)", (void *)regs->psw.addr);
151 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
152 "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
153 mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
154 mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
155 mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
156 mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
157 mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
159 printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));
161 printk("\n%s GPRS: " FOURLONG, mode,
162 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
164 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
166 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
168 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
172 void show_regs(struct pt_regs *regs)
174 show_regs_print_info(KERN_DEFAULT);
175 show_registers(regs);
176 /* Show stack backtrace if pt_regs is from kernel mode */
177 if (!user_mode(regs))
178 show_trace(NULL, (unsigned long *) regs->gprs[15]);
179 show_last_breaking_event(regs);
182 static DEFINE_SPINLOCK(die_lock);
184 void die(struct pt_regs *regs, const char *str)
186 static int die_counter;
192 spin_lock_irq(&die_lock);
194 printk("%s: %04x [#%d] ", str, regs->int_code & 0xffff, ++die_counter);
195 #ifdef CONFIG_PREEMPT
201 #ifdef CONFIG_DEBUG_PAGEALLOC
202 printk("DEBUG_PAGEALLOC");
205 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
209 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
210 spin_unlock_irq(&die_lock);
212 panic("Fatal exception in interrupt");
214 panic("Fatal exception: panic_on_oops");