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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Stack dumping functions
4 *
5 * Copyright IBM Corp. 1999, 2013
6 */
7
8#include <linux/kallsyms.h>
9#include <linux/hardirq.h>
10#include <linux/kprobes.h>
11#include <linux/utsname.h>
12#include <linux/export.h>
13#include <linux/kdebug.h>
14#include <linux/ptrace.h>
15#include <linux/mm.h>
16#include <linux/module.h>
17#include <linux/sched.h>
18#include <linux/sched/debug.h>
19#include <linux/sched/task_stack.h>
20#include <asm/processor.h>
21#include <asm/debug.h>
22#include <asm/dis.h>
23#include <asm/ipl.h>
24
25/*
26 * For dump_trace we have tree different stack to consider:
27 * - the panic stack which is used if the kernel stack has overflown
28 * - the asynchronous interrupt stack (cpu related)
29 * - the synchronous kernel stack (process related)
30 * The stack trace can start at any of the three stacks and can potentially
31 * touch all of them. The order is: panic stack, async stack, sync stack.
32 */
33static unsigned long
34__dump_trace(dump_trace_func_t func, void *data, unsigned long sp,
35 unsigned long low, unsigned long high)
36{
37 struct stack_frame *sf;
38 struct pt_regs *regs;
39
40 while (1) {
41 if (sp < low || sp > high - sizeof(*sf))
42 return sp;
43 sf = (struct stack_frame *) sp;
44 if (func(data, sf->gprs[8], 0))
45 return sp;
46 /* Follow the backchain. */
47 while (1) {
48 low = sp;
49 sp = sf->back_chain;
50 if (!sp)
51 break;
52 if (sp <= low || sp > high - sizeof(*sf))
53 return sp;
54 sf = (struct stack_frame *) sp;
55 if (func(data, sf->gprs[8], 1))
56 return sp;
57 }
58 /* Zero backchain detected, check for interrupt frame. */
59 sp = (unsigned long) (sf + 1);
60 if (sp <= low || sp > high - sizeof(*regs))
61 return sp;
62 regs = (struct pt_regs *) sp;
63 if (!user_mode(regs)) {
64 if (func(data, regs->psw.addr, 1))
65 return sp;
66 }
67 low = sp;
68 sp = regs->gprs[15];
69 }
70}
71
72void dump_trace(dump_trace_func_t func, void *data, struct task_struct *task,
73 unsigned long sp)
74{
75 unsigned long frame_size;
76
77 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
78#ifdef CONFIG_CHECK_STACK
79 sp = __dump_trace(func, data, sp,
80 S390_lowcore.panic_stack + frame_size - PAGE_SIZE,
81 S390_lowcore.panic_stack + frame_size);
82#endif
83 sp = __dump_trace(func, data, sp,
84 S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
85 S390_lowcore.async_stack + frame_size);
86 task = task ?: current;
87 __dump_trace(func, data, sp,
88 (unsigned long)task_stack_page(task),
89 (unsigned long)task_stack_page(task) + THREAD_SIZE);
90}
91EXPORT_SYMBOL_GPL(dump_trace);
92
93static int show_address(void *data, unsigned long address, int reliable)
94{
95 if (reliable)
96 printk(" [<%016lx>] %pSR \n", address, (void *)address);
97 else
98 printk("([<%016lx>] %pSR)\n", address, (void *)address);
99 return 0;
100}
101
102void show_stack(struct task_struct *task, unsigned long *stack)
103{
104 unsigned long sp = (unsigned long) stack;
105
106 if (!sp)
107 sp = task ? task->thread.ksp : current_stack_pointer();
108 printk("Call Trace:\n");
109 dump_trace(show_address, NULL, task, sp);
110 if (!task)
111 task = current;
112 debug_show_held_locks(task);
113}
114
115static void show_last_breaking_event(struct pt_regs *regs)
116{
117 printk("Last Breaking-Event-Address:\n");
118 printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
119}
120
121void show_registers(struct pt_regs *regs)
122{
123 struct psw_bits *psw = &psw_bits(regs->psw);
124 char *mode;
125
126 mode = user_mode(regs) ? "User" : "Krnl";
127 printk("%s PSW : %p %p", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
128 if (!user_mode(regs))
129 pr_cont(" (%pSR)", (void *)regs->psw.addr);
130 pr_cont("\n");
131 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
132 "P:%x AS:%x CC:%x PM:%x", psw->per, psw->dat, psw->io, psw->ext,
133 psw->key, psw->mcheck, psw->wait, psw->pstate, psw->as, psw->cc, psw->pm);
134 pr_cont(" RI:%x EA:%x\n", psw->ri, psw->eaba);
135 printk("%s GPRS: %016lx %016lx %016lx %016lx\n", mode,
136 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
137 printk(" %016lx %016lx %016lx %016lx\n",
138 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
139 printk(" %016lx %016lx %016lx %016lx\n",
140 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
141 printk(" %016lx %016lx %016lx %016lx\n",
142 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
143 show_code(regs);
144}
145
146void show_regs(struct pt_regs *regs)
147{
148 show_regs_print_info(KERN_DEFAULT);
149 show_registers(regs);
150 /* Show stack backtrace if pt_regs is from kernel mode */
151 if (!user_mode(regs))
152 show_stack(NULL, (unsigned long *) regs->gprs[15]);
153 show_last_breaking_event(regs);
154}
155
156static DEFINE_SPINLOCK(die_lock);
157
158void die(struct pt_regs *regs, const char *str)
159{
160 static int die_counter;
161
162 oops_enter();
163 lgr_info_log();
164 debug_stop_all();
165 console_verbose();
166 spin_lock_irq(&die_lock);
167 bust_spinlocks(1);
168 printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff,
169 regs->int_code >> 17, ++die_counter);
170#ifdef CONFIG_PREEMPT
171 pr_cont("PREEMPT ");
172#endif
173#ifdef CONFIG_SMP
174 pr_cont("SMP ");
175#endif
176 if (debug_pagealloc_enabled())
177 pr_cont("DEBUG_PAGEALLOC");
178 pr_cont("\n");
179 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
180 print_modules();
181 show_regs(regs);
182 bust_spinlocks(0);
183 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
184 spin_unlock_irq(&die_lock);
185 if (in_interrupt())
186 panic("Fatal exception in interrupt");
187 if (panic_on_oops)
188 panic("Fatal exception: panic_on_oops");
189 oops_exit();
190 do_exit(SIGSEGV);
191}
1/*
2 * Stack dumping functions
3 *
4 * Copyright IBM Corp. 1999, 2013
5 */
6
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>
18#include <asm/dis.h>
19#include <asm/ipl.h>
20
21#ifndef CONFIG_64BIT
22#define LONG "%08lx "
23#define FOURLONG "%08lx %08lx %08lx %08lx\n"
24static int kstack_depth_to_print = 12;
25#else /* CONFIG_64BIT */
26#define LONG "%016lx "
27#define FOURLONG "%016lx %016lx %016lx %016lx\n"
28static int kstack_depth_to_print = 20;
29#endif /* CONFIG_64BIT */
30
31/*
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.
38 */
39static unsigned long
40__show_trace(unsigned long sp, unsigned long low, unsigned long high)
41{
42 struct stack_frame *sf;
43 struct pt_regs *regs;
44 unsigned long addr;
45
46 while (1) {
47 sp = sp & PSW_ADDR_INSN;
48 if (sp < low || sp > high - sizeof(*sf))
49 return sp;
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. */
54 while (1) {
55 low = sp;
56 sp = sf->back_chain & PSW_ADDR_INSN;
57 if (!sp)
58 break;
59 if (sp <= low || sp > high - sizeof(*sf))
60 return sp;
61 sf = (struct stack_frame *) sp;
62 addr = sf->gprs[8] & PSW_ADDR_INSN;
63 printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
64 }
65 /* Zero backchain detected, check for interrupt frame. */
66 sp = (unsigned long) (sf + 1);
67 if (sp <= low || sp > high - sizeof(*regs))
68 return sp;
69 regs = (struct pt_regs *) sp;
70 addr = regs->psw.addr & PSW_ADDR_INSN;
71 printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
72 low = sp;
73 sp = regs->gprs[15];
74 }
75}
76
77static void show_trace(struct task_struct *task, unsigned long *stack)
78{
79 const unsigned long frame_size =
80 STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
81 register unsigned long __r15 asm ("15");
82 unsigned long sp;
83
84 sp = (unsigned long) stack;
85 if (!sp)
86 sp = task ? task->thread.ksp : __r15;
87 printk("Call Trace:\n");
88#ifdef CONFIG_CHECK_STACK
89 sp = __show_trace(sp,
90 S390_lowcore.panic_stack + frame_size - 4096,
91 S390_lowcore.panic_stack + frame_size);
92#endif
93 sp = __show_trace(sp,
94 S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
95 S390_lowcore.async_stack + frame_size);
96 if (task)
97 __show_trace(sp, (unsigned long) task_stack_page(task),
98 (unsigned long) task_stack_page(task) + THREAD_SIZE);
99 else
100 __show_trace(sp, S390_lowcore.thread_info,
101 S390_lowcore.thread_info + THREAD_SIZE);
102 if (!task)
103 task = current;
104 debug_show_held_locks(task);
105}
106
107void show_stack(struct task_struct *task, unsigned long *sp)
108{
109 register unsigned long *__r15 asm ("15");
110 unsigned long *stack;
111 int i;
112
113 if (!sp)
114 stack = task ? (unsigned long *) task->thread.ksp : __r15;
115 else
116 stack = sp;
117
118 for (i = 0; i < kstack_depth_to_print; i++) {
119 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
120 break;
121 if ((i * sizeof(long) % 32) == 0)
122 printk("%s ", i == 0 ? "" : "\n");
123 printk(LONG, *stack++);
124 }
125 printk("\n");
126 show_trace(task, sp);
127}
128
129static void show_last_breaking_event(struct pt_regs *regs)
130{
131#ifdef CONFIG_64BIT
132 printk("Last Breaking-Event-Address:\n");
133 printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
134#endif
135}
136
137static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
138{
139 return (regs->psw.mask & bits) / ((~bits + 1) & bits);
140}
141
142void show_registers(struct pt_regs *regs)
143{
144 char *mode;
145
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);
150 printk("\n");
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));
158#ifdef CONFIG_64BIT
159 printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));
160#endif
161 printk("\n%s GPRS: " FOURLONG, mode,
162 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
163 printk(" " FOURLONG,
164 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
165 printk(" " FOURLONG,
166 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
167 printk(" " FOURLONG,
168 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
169 show_code(regs);
170}
171
172void show_regs(struct pt_regs *regs)
173{
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);
180}
181
182static DEFINE_SPINLOCK(die_lock);
183
184void die(struct pt_regs *regs, const char *str)
185{
186 static int die_counter;
187
188 oops_enter();
189 lgr_info_log();
190 debug_stop_all();
191 console_verbose();
192 spin_lock_irq(&die_lock);
193 bust_spinlocks(1);
194 printk("%s: %04x [#%d] ", str, regs->int_code & 0xffff, ++die_counter);
195#ifdef CONFIG_PREEMPT
196 printk("PREEMPT ");
197#endif
198#ifdef CONFIG_SMP
199 printk("SMP ");
200#endif
201#ifdef CONFIG_DEBUG_PAGEALLOC
202 printk("DEBUG_PAGEALLOC");
203#endif
204 printk("\n");
205 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
206 print_modules();
207 show_regs(regs);
208 bust_spinlocks(0);
209 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
210 spin_unlock_irq(&die_lock);
211 if (in_interrupt())
212 panic("Fatal exception in interrupt");
213 if (panic_on_oops)
214 panic("Fatal exception: panic_on_oops");
215 oops_exit();
216 do_exit(SIGSEGV);
217}