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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#include <asm/unwind.h>
25
26const char *stack_type_name(enum stack_type type)
27{
28 switch (type) {
29 case STACK_TYPE_TASK:
30 return "task";
31 case STACK_TYPE_IRQ:
32 return "irq";
33 case STACK_TYPE_NODAT:
34 return "nodat";
35 case STACK_TYPE_RESTART:
36 return "restart";
37 default:
38 return "unknown";
39 }
40}
41
42static inline bool in_stack(unsigned long sp, struct stack_info *info,
43 enum stack_type type, unsigned long low,
44 unsigned long high)
45{
46 if (sp < low || sp >= high)
47 return false;
48 info->type = type;
49 info->begin = low;
50 info->end = high;
51 return true;
52}
53
54static bool in_task_stack(unsigned long sp, struct task_struct *task,
55 struct stack_info *info)
56{
57 unsigned long stack;
58
59 stack = (unsigned long) task_stack_page(task);
60 return in_stack(sp, info, STACK_TYPE_TASK, stack, stack + THREAD_SIZE);
61}
62
63static bool in_irq_stack(unsigned long sp, struct stack_info *info)
64{
65 unsigned long frame_size, top;
66
67 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
68 top = S390_lowcore.async_stack + frame_size;
69 return in_stack(sp, info, STACK_TYPE_IRQ, top - THREAD_SIZE, top);
70}
71
72static bool in_nodat_stack(unsigned long sp, struct stack_info *info)
73{
74 unsigned long frame_size, top;
75
76 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
77 top = S390_lowcore.nodat_stack + frame_size;
78 return in_stack(sp, info, STACK_TYPE_NODAT, top - THREAD_SIZE, top);
79}
80
81static bool in_restart_stack(unsigned long sp, struct stack_info *info)
82{
83 unsigned long frame_size, top;
84
85 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
86 top = S390_lowcore.restart_stack + frame_size;
87 return in_stack(sp, info, STACK_TYPE_RESTART, top - THREAD_SIZE, top);
88}
89
90int get_stack_info(unsigned long sp, struct task_struct *task,
91 struct stack_info *info, unsigned long *visit_mask)
92{
93 if (!sp)
94 goto unknown;
95
96 task = task ? : current;
97
98 /* Check per-task stack */
99 if (in_task_stack(sp, task, info))
100 goto recursion_check;
101
102 if (task != current)
103 goto unknown;
104
105 /* Check per-cpu stacks */
106 if (!in_irq_stack(sp, info) &&
107 !in_nodat_stack(sp, info) &&
108 !in_restart_stack(sp, info))
109 goto unknown;
110
111recursion_check:
112 /*
113 * Make sure we don't iterate through any given stack more than once.
114 * If it comes up a second time then there's something wrong going on:
115 * just break out and report an unknown stack type.
116 */
117 if (*visit_mask & (1UL << info->type))
118 goto unknown;
119 *visit_mask |= 1UL << info->type;
120 return 0;
121unknown:
122 info->type = STACK_TYPE_UNKNOWN;
123 return -EINVAL;
124}
125
126void show_stack(struct task_struct *task, unsigned long *stack)
127{
128 struct unwind_state state;
129
130 printk("Call Trace:\n");
131 if (!task)
132 task = current;
133 unwind_for_each_frame(&state, task, NULL, (unsigned long) stack)
134 printk(state.reliable ? " [<%016lx>] %pSR \n" :
135 "([<%016lx>] %pSR)\n",
136 state.ip, (void *) state.ip);
137 debug_show_held_locks(task ? : current);
138}
139
140static void show_last_breaking_event(struct pt_regs *regs)
141{
142 printk("Last Breaking-Event-Address:\n");
143 printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
144}
145
146void show_registers(struct pt_regs *regs)
147{
148 struct psw_bits *psw = &psw_bits(regs->psw);
149 char *mode;
150
151 mode = user_mode(regs) ? "User" : "Krnl";
152 printk("%s PSW : %px %px", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
153 if (!user_mode(regs))
154 pr_cont(" (%pSR)", (void *)regs->psw.addr);
155 pr_cont("\n");
156 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
157 "P:%x AS:%x CC:%x PM:%x", psw->per, psw->dat, psw->io, psw->ext,
158 psw->key, psw->mcheck, psw->wait, psw->pstate, psw->as, psw->cc, psw->pm);
159 pr_cont(" RI:%x EA:%x\n", psw->ri, psw->eaba);
160 printk("%s GPRS: %016lx %016lx %016lx %016lx\n", mode,
161 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
162 printk(" %016lx %016lx %016lx %016lx\n",
163 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
164 printk(" %016lx %016lx %016lx %016lx\n",
165 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
166 printk(" %016lx %016lx %016lx %016lx\n",
167 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
168 show_code(regs);
169}
170
171void show_regs(struct pt_regs *regs)
172{
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_stack(NULL, (unsigned long *) regs->gprs[15]);
178 show_last_breaking_event(regs);
179}
180
181static DEFINE_SPINLOCK(die_lock);
182
183void die(struct pt_regs *regs, const char *str)
184{
185 static int die_counter;
186
187 oops_enter();
188 lgr_info_log();
189 debug_stop_all();
190 console_verbose();
191 spin_lock_irq(&die_lock);
192 bust_spinlocks(1);
193 printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff,
194 regs->int_code >> 17, ++die_counter);
195#ifdef CONFIG_PREEMPT
196 pr_cont("PREEMPT ");
197#endif
198 pr_cont("SMP ");
199 if (debug_pagealloc_enabled())
200 pr_cont("DEBUG_PAGEALLOC");
201 pr_cont("\n");
202 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
203 print_modules();
204 show_regs(regs);
205 bust_spinlocks(0);
206 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
207 spin_unlock_irq(&die_lock);
208 if (in_interrupt())
209 panic("Fatal exception in interrupt");
210 if (panic_on_oops)
211 panic("Fatal exception: panic_on_oops");
212 oops_exit();
213 do_exit(SIGSEGV);
214}
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/mm.h>
15#include <linux/module.h>
16#include <linux/sched.h>
17#include <asm/processor.h>
18#include <asm/debug.h>
19#include <asm/dis.h>
20#include <asm/ipl.h>
21
22/*
23 * For dump_trace we have tree different stack to consider:
24 * - the panic stack which is used if the kernel stack has overflown
25 * - the asynchronous interrupt stack (cpu related)
26 * - the synchronous kernel stack (process related)
27 * The stack trace can start at any of the three stacks and can potentially
28 * touch all of them. The order is: panic stack, async stack, sync stack.
29 */
30static unsigned long
31__dump_trace(dump_trace_func_t func, void *data, unsigned long sp,
32 unsigned long low, unsigned long high)
33{
34 struct stack_frame *sf;
35 struct pt_regs *regs;
36
37 while (1) {
38 if (sp < low || sp > high - sizeof(*sf))
39 return sp;
40 sf = (struct stack_frame *) sp;
41 /* Follow the backchain. */
42 while (1) {
43 if (func(data, sf->gprs[8]))
44 return sp;
45 low = sp;
46 sp = sf->back_chain;
47 if (!sp)
48 break;
49 if (sp <= low || sp > high - sizeof(*sf))
50 return sp;
51 sf = (struct stack_frame *) sp;
52 }
53 /* Zero backchain detected, check for interrupt frame. */
54 sp = (unsigned long) (sf + 1);
55 if (sp <= low || sp > high - sizeof(*regs))
56 return sp;
57 regs = (struct pt_regs *) sp;
58 if (!user_mode(regs)) {
59 if (func(data, regs->psw.addr))
60 return sp;
61 }
62 low = sp;
63 sp = regs->gprs[15];
64 }
65}
66
67void dump_trace(dump_trace_func_t func, void *data, struct task_struct *task,
68 unsigned long sp)
69{
70 unsigned long frame_size;
71
72 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
73#ifdef CONFIG_CHECK_STACK
74 sp = __dump_trace(func, data, sp,
75 S390_lowcore.panic_stack + frame_size - 4096,
76 S390_lowcore.panic_stack + frame_size);
77#endif
78 sp = __dump_trace(func, data, sp,
79 S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
80 S390_lowcore.async_stack + frame_size);
81 if (task)
82 __dump_trace(func, data, sp,
83 (unsigned long)task_stack_page(task),
84 (unsigned long)task_stack_page(task) + THREAD_SIZE);
85 else
86 __dump_trace(func, data, sp,
87 S390_lowcore.thread_info,
88 S390_lowcore.thread_info + THREAD_SIZE);
89}
90EXPORT_SYMBOL_GPL(dump_trace);
91
92static int show_address(void *data, unsigned long address)
93{
94 printk("([<%016lx>] %pSR)\n", address, (void *)address);
95 return 0;
96}
97
98static void show_trace(struct task_struct *task, unsigned long sp)
99{
100 if (!sp)
101 sp = task ? task->thread.ksp : current_stack_pointer();
102 printk("Call Trace:\n");
103 dump_trace(show_address, NULL, task, sp);
104 if (!task)
105 task = current;
106 debug_show_held_locks(task);
107}
108
109void show_stack(struct task_struct *task, unsigned long *sp)
110{
111 unsigned long *stack;
112 int i;
113
114 stack = sp;
115 if (!stack) {
116 if (!task)
117 stack = (unsigned long *)current_stack_pointer();
118 else
119 stack = (unsigned long *)task->thread.ksp;
120 }
121 for (i = 0; i < 20; i++) {
122 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
123 break;
124 if ((i * sizeof(long) % 32) == 0)
125 printk("%s ", i == 0 ? "" : "\n");
126 printk("%016lx ", *stack++);
127 }
128 printk("\n");
129 show_trace(task, (unsigned long)sp);
130}
131
132static void show_last_breaking_event(struct pt_regs *regs)
133{
134 printk("Last Breaking-Event-Address:\n");
135 printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
136}
137
138void show_registers(struct pt_regs *regs)
139{
140 struct psw_bits *psw = &psw_bits(regs->psw);
141 char *mode;
142
143 mode = user_mode(regs) ? "User" : "Krnl";
144 printk("%s PSW : %p %p", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
145 if (!user_mode(regs))
146 printk(" (%pSR)", (void *)regs->psw.addr);
147 printk("\n");
148 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
149 "P:%x AS:%x CC:%x PM:%x", psw->r, psw->t, psw->i, psw->e,
150 psw->key, psw->m, psw->w, psw->p, psw->as, psw->cc, psw->pm);
151 printk(" RI:%x EA:%x", psw->ri, psw->eaba);
152 printk("\n%s GPRS: %016lx %016lx %016lx %016lx\n", mode,
153 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
154 printk(" %016lx %016lx %016lx %016lx\n",
155 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
156 printk(" %016lx %016lx %016lx %016lx\n",
157 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
158 printk(" %016lx %016lx %016lx %016lx\n",
159 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
160 show_code(regs);
161}
162
163void show_regs(struct pt_regs *regs)
164{
165 show_regs_print_info(KERN_DEFAULT);
166 show_registers(regs);
167 /* Show stack backtrace if pt_regs is from kernel mode */
168 if (!user_mode(regs))
169 show_trace(NULL, regs->gprs[15]);
170 show_last_breaking_event(regs);
171}
172
173static DEFINE_SPINLOCK(die_lock);
174
175void die(struct pt_regs *regs, const char *str)
176{
177 static int die_counter;
178
179 oops_enter();
180 lgr_info_log();
181 debug_stop_all();
182 console_verbose();
183 spin_lock_irq(&die_lock);
184 bust_spinlocks(1);
185 printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff,
186 regs->int_code >> 17, ++die_counter);
187#ifdef CONFIG_PREEMPT
188 printk("PREEMPT ");
189#endif
190#ifdef CONFIG_SMP
191 printk("SMP ");
192#endif
193 if (debug_pagealloc_enabled())
194 printk("DEBUG_PAGEALLOC");
195 printk("\n");
196 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
197 print_modules();
198 show_regs(regs);
199 bust_spinlocks(0);
200 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
201 spin_unlock_irq(&die_lock);
202 if (in_interrupt())
203 panic("Fatal exception in interrupt");
204 if (panic_on_oops)
205 panic("Fatal exception: panic_on_oops");
206 oops_exit();
207 do_exit(SIGSEGV);
208}