| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Stack dumping functions |
| * |
| * Copyright IBM Corp. 1999, 2013 |
| */ |
| |
| #include <linux/kallsyms.h> |
| #include <linux/hardirq.h> |
| #include <linux/kprobes.h> |
| #include <linux/utsname.h> |
| #include <linux/export.h> |
| #include <linux/kdebug.h> |
| #include <linux/ptrace.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/sched.h> |
| #include <linux/sched/debug.h> |
| #include <linux/sched/task_stack.h> |
| #include <asm/processor.h> |
| #include <asm/debug.h> |
| #include <asm/dis.h> |
| #include <asm/ipl.h> |
| #include <asm/unwind.h> |
| |
| const char *stack_type_name(enum stack_type type) |
| { |
| switch (type) { |
| case STACK_TYPE_TASK: |
| return "task"; |
| case STACK_TYPE_IRQ: |
| return "irq"; |
| case STACK_TYPE_NODAT: |
| return "nodat"; |
| case STACK_TYPE_RESTART: |
| return "restart"; |
| default: |
| return "unknown"; |
| } |
| } |
| |
| static inline bool in_stack(unsigned long sp, struct stack_info *info, |
| enum stack_type type, unsigned long low, |
| unsigned long high) |
| { |
| if (sp < low || sp >= high) |
| return false; |
| info->type = type; |
| info->begin = low; |
| info->end = high; |
| return true; |
| } |
| |
| static bool in_task_stack(unsigned long sp, struct task_struct *task, |
| struct stack_info *info) |
| { |
| unsigned long stack; |
| |
| stack = (unsigned long) task_stack_page(task); |
| return in_stack(sp, info, STACK_TYPE_TASK, stack, stack + THREAD_SIZE); |
| } |
| |
| static bool in_irq_stack(unsigned long sp, struct stack_info *info) |
| { |
| unsigned long frame_size, top; |
| |
| frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs); |
| top = S390_lowcore.async_stack + frame_size; |
| return in_stack(sp, info, STACK_TYPE_IRQ, top - THREAD_SIZE, top); |
| } |
| |
| static bool in_nodat_stack(unsigned long sp, struct stack_info *info) |
| { |
| unsigned long frame_size, top; |
| |
| frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs); |
| top = S390_lowcore.nodat_stack + frame_size; |
| return in_stack(sp, info, STACK_TYPE_NODAT, top - THREAD_SIZE, top); |
| } |
| |
| static bool in_restart_stack(unsigned long sp, struct stack_info *info) |
| { |
| unsigned long frame_size, top; |
| |
| frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs); |
| top = S390_lowcore.restart_stack + frame_size; |
| return in_stack(sp, info, STACK_TYPE_RESTART, top - THREAD_SIZE, top); |
| } |
| |
| int get_stack_info(unsigned long sp, struct task_struct *task, |
| struct stack_info *info, unsigned long *visit_mask) |
| { |
| if (!sp) |
| goto unknown; |
| |
| task = task ? : current; |
| |
| /* Check per-task stack */ |
| if (in_task_stack(sp, task, info)) |
| goto recursion_check; |
| |
| if (task != current) |
| goto unknown; |
| |
| /* Check per-cpu stacks */ |
| if (!in_irq_stack(sp, info) && |
| !in_nodat_stack(sp, info) && |
| !in_restart_stack(sp, info)) |
| goto unknown; |
| |
| recursion_check: |
| /* |
| * Make sure we don't iterate through any given stack more than once. |
| * If it comes up a second time then there's something wrong going on: |
| * just break out and report an unknown stack type. |
| */ |
| if (*visit_mask & (1UL << info->type)) { |
| printk_deferred_once(KERN_WARNING |
| "WARNING: stack recursion on stack type %d\n", |
| info->type); |
| goto unknown; |
| } |
| *visit_mask |= 1UL << info->type; |
| return 0; |
| unknown: |
| info->type = STACK_TYPE_UNKNOWN; |
| return -EINVAL; |
| } |
| |
| void show_stack(struct task_struct *task, unsigned long *stack) |
| { |
| struct unwind_state state; |
| |
| printk("Call Trace:\n"); |
| if (!task) |
| task = current; |
| unwind_for_each_frame(&state, task, NULL, (unsigned long) stack) |
| printk(state.reliable ? " [<%016lx>] %pSR \n" : |
| "([<%016lx>] %pSR)\n", |
| state.ip, (void *) state.ip); |
| debug_show_held_locks(task ? : current); |
| } |
| |
| static void show_last_breaking_event(struct pt_regs *regs) |
| { |
| printk("Last Breaking-Event-Address:\n"); |
| printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]); |
| } |
| |
| void show_registers(struct pt_regs *regs) |
| { |
| struct psw_bits *psw = &psw_bits(regs->psw); |
| char *mode; |
| |
| mode = user_mode(regs) ? "User" : "Krnl"; |
| printk("%s PSW : %px %px", mode, (void *)regs->psw.mask, (void *)regs->psw.addr); |
| if (!user_mode(regs)) |
| pr_cont(" (%pSR)", (void *)regs->psw.addr); |
| pr_cont("\n"); |
| printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x " |
| "P:%x AS:%x CC:%x PM:%x", psw->per, psw->dat, psw->io, psw->ext, |
| psw->key, psw->mcheck, psw->wait, psw->pstate, psw->as, psw->cc, psw->pm); |
| pr_cont(" RI:%x EA:%x\n", psw->ri, psw->eaba); |
| printk("%s GPRS: %016lx %016lx %016lx %016lx\n", mode, |
| regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]); |
| printk(" %016lx %016lx %016lx %016lx\n", |
| regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]); |
| printk(" %016lx %016lx %016lx %016lx\n", |
| regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]); |
| printk(" %016lx %016lx %016lx %016lx\n", |
| regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]); |
| show_code(regs); |
| } |
| |
| void show_regs(struct pt_regs *regs) |
| { |
| show_regs_print_info(KERN_DEFAULT); |
| show_registers(regs); |
| /* Show stack backtrace if pt_regs is from kernel mode */ |
| if (!user_mode(regs)) |
| show_stack(NULL, (unsigned long *) regs->gprs[15]); |
| show_last_breaking_event(regs); |
| } |
| |
| static DEFINE_SPINLOCK(die_lock); |
| |
| void die(struct pt_regs *regs, const char *str) |
| { |
| static int die_counter; |
| |
| oops_enter(); |
| lgr_info_log(); |
| debug_stop_all(); |
| console_verbose(); |
| spin_lock_irq(&die_lock); |
| bust_spinlocks(1); |
| printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff, |
| regs->int_code >> 17, ++die_counter); |
| #ifdef CONFIG_PREEMPT |
| pr_cont("PREEMPT "); |
| #endif |
| #ifdef CONFIG_SMP |
| pr_cont("SMP "); |
| #endif |
| if (debug_pagealloc_enabled()) |
| pr_cont("DEBUG_PAGEALLOC"); |
| pr_cont("\n"); |
| notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV); |
| print_modules(); |
| show_regs(regs); |
| bust_spinlocks(0); |
| add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); |
| spin_unlock_irq(&die_lock); |
| if (in_interrupt()) |
| panic("Fatal exception in interrupt"); |
| if (panic_on_oops) |
| panic("Fatal exception: panic_on_oops"); |
| oops_exit(); |
| do_exit(SIGSEGV); |
| } |