arch/x86/include/asm/unwind.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_UNWIND_H
   3 #define _ASM_X86_UNWIND_H
   4
   5 #include <linux/sched.h>
   6 #include <linux/ftrace.h>
   7 #include <asm/ptrace.h>
   8 #include <asm/stacktrace.h>
   9
  10 struct unwind_state {
  11         struct stack_info stack_info;
  12         unsigned long stack_mask;
  13         struct task_struct *task;
  14         int graph_idx;
  15         bool error;
  16 #if defined(CONFIG_UNWINDER_ORC)
  17         bool signal, full_regs;
  18         unsigned long sp, bp, ip;
  19         struct pt_regs *regs;
  20 #elif defined(CONFIG_UNWINDER_FRAME_POINTER)
  21         bool got_irq;
  22         unsigned long *bp, *orig_sp, ip;
  23         struct pt_regs *regs;
  24 #else
  25         unsigned long *sp;
  26 #endif
  27 };
  28
  29 void __unwind_start(struct unwind_state *state, struct task_struct *task,
  30                     struct pt_regs *regs, unsigned long *first_frame);
  31 bool unwind_next_frame(struct unwind_state *state);
  32 unsigned long unwind_get_return_address(struct unwind_state *state);
  33 unsigned long *unwind_get_return_address_ptr(struct unwind_state *state);
  34
  35 static inline bool unwind_done(struct unwind_state *state)
  36 {
  37         return state->stack_info.type == STACK_TYPE_UNKNOWN;
  38 }
  39
  40 static inline bool unwind_error(struct unwind_state *state)
  41 {
  42         return state->error;
  43 }
  44
  45 static inline
  46 void unwind_start(struct unwind_state *state, struct task_struct *task,
  47                   struct pt_regs *regs, unsigned long *first_frame)
  48 {
  49         first_frame = first_frame ? : get_stack_pointer(task, regs);
  50
  51         __unwind_start(state, task, regs, first_frame);
  52 }
  53
  54 #if defined(CONFIG_UNWINDER_ORC) || defined(CONFIG_UNWINDER_FRAME_POINTER)
  55 static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state)
  56 {
  57         if (unwind_done(state))
  58                 return NULL;
  59
  60         return state->regs;
  61 }
  62 #else
  63 static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state)
  64 {
  65         return NULL;
  66 }
  67 #endif
  68
  69 #ifdef CONFIG_UNWINDER_ORC
  70 void unwind_init(void);
  71 void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
  72                         void *orc, size_t orc_size);
  73 #else
  74 static inline void unwind_init(void) {}
  75 static inline
  76 void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
  77                         void *orc, size_t orc_size) {}
  78 #endif
  79
  80 /*
  81  * This disables KASAN checking when reading a value from another task's stack,
  82  * since the other task could be running on another CPU and could have poisoned
  83  * the stack in the meantime.
  84  */
  85 #define READ_ONCE_TASK_STACK(task, x)                   \
  86 ({                                                      \
  87         unsigned long val;                              \
  88         if (task == current)                            \
  89                 val = READ_ONCE(x);                     \
  90         else                                            \
  91                 val = READ_ONCE_NOCHECK(x);             \
  92         val;                                            \
  93 })
  94
  95 static inline bool task_on_another_cpu(struct task_struct *task)
  96 {
  97 #ifdef CONFIG_SMP
  98         return task != current && task->on_cpu;
  99 #else
 100         return false;
 101 #endif
 102 }
 103
 104 #endif /* _ASM_X86_UNWIND_H */