1 // SPDX-License-Identifier: GPL-2.0
3 * Stack dumping functions
5 * Copyright IBM Corp. 1999, 2013
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>
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>
24 #include <asm/unwind.h>
26 const char *stack_type_name(enum stack_type type)
33 case STACK_TYPE_NODAT:
35 case STACK_TYPE_RESTART:
41 EXPORT_SYMBOL_GPL(stack_type_name);
43 static inline bool in_stack(unsigned long sp, struct stack_info *info,
44 enum stack_type type, unsigned long low,
47 if (sp < low || sp >= high)
55 static bool in_task_stack(unsigned long sp, struct task_struct *task,
56 struct stack_info *info)
60 stack = (unsigned long) task_stack_page(task);
61 return in_stack(sp, info, STACK_TYPE_TASK, stack, stack + THREAD_SIZE);
64 static bool in_irq_stack(unsigned long sp, struct stack_info *info)
66 unsigned long frame_size, top;
68 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
69 top = S390_lowcore.async_stack + frame_size;
70 return in_stack(sp, info, STACK_TYPE_IRQ, top - THREAD_SIZE, top);
73 static bool in_nodat_stack(unsigned long sp, struct stack_info *info)
75 unsigned long frame_size, top;
77 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
78 top = S390_lowcore.nodat_stack + frame_size;
79 return in_stack(sp, info, STACK_TYPE_NODAT, top - THREAD_SIZE, top);
82 static bool in_restart_stack(unsigned long sp, struct stack_info *info)
84 unsigned long frame_size, top;
86 frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
87 top = S390_lowcore.restart_stack + frame_size;
88 return in_stack(sp, info, STACK_TYPE_RESTART, top - THREAD_SIZE, top);
91 int get_stack_info(unsigned long sp, struct task_struct *task,
92 struct stack_info *info, unsigned long *visit_mask)
97 /* Sanity check: ABI requires SP to be aligned 8 bytes. */
101 /* Check per-task stack */
102 if (in_task_stack(sp, task, info))
103 goto recursion_check;
108 /* Check per-cpu stacks */
109 if (!in_irq_stack(sp, info) &&
110 !in_nodat_stack(sp, info) &&
111 !in_restart_stack(sp, info))
116 * Make sure we don't iterate through any given stack more than once.
117 * If it comes up a second time then there's something wrong going on:
118 * just break out and report an unknown stack type.
120 if (*visit_mask & (1UL << info->type))
122 *visit_mask |= 1UL << info->type;
125 info->type = STACK_TYPE_UNKNOWN;
129 void show_stack(struct task_struct *task, unsigned long *stack)
131 struct unwind_state state;
133 printk("Call Trace:\n");
134 unwind_for_each_frame(&state, task, NULL, (unsigned long) stack)
135 printk(state.reliable ? " [<%016lx>] %pSR \n" :
136 "([<%016lx>] %pSR)\n",
137 state.ip, (void *) state.ip);
138 debug_show_held_locks(task ? : current);
141 static void show_last_breaking_event(struct pt_regs *regs)
143 printk("Last Breaking-Event-Address:\n");
144 printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
147 void show_registers(struct pt_regs *regs)
149 struct psw_bits *psw = &psw_bits(regs->psw);
152 mode = user_mode(regs) ? "User" : "Krnl";
153 printk("%s PSW : %px %px", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
154 if (!user_mode(regs))
155 pr_cont(" (%pSR)", (void *)regs->psw.addr);
157 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
158 "P:%x AS:%x CC:%x PM:%x", psw->per, psw->dat, psw->io, psw->ext,
159 psw->key, psw->mcheck, psw->wait, psw->pstate, psw->as, psw->cc, psw->pm);
160 pr_cont(" RI:%x EA:%x\n", psw->ri, psw->eaba);
161 printk("%s GPRS: %016lx %016lx %016lx %016lx\n", mode,
162 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
163 printk(" %016lx %016lx %016lx %016lx\n",
164 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
165 printk(" %016lx %016lx %016lx %016lx\n",
166 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
167 printk(" %016lx %016lx %016lx %016lx\n",
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_stack(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 ilc:%d [#%d] ", str, regs->int_code & 0xffff,
195 regs->int_code >> 17, ++die_counter);
196 #ifdef CONFIG_PREEMPT
198 #elif defined(CONFIG_PREEMPT_RT)
199 pr_cont("PREEMPT_RT ");
202 if (debug_pagealloc_enabled())
203 pr_cont("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");