arch/cris/arch-v10/kernel/traps.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Helper functions for trap handlers
   4  *
   5  * Copyright (C) 2000-2007, Axis Communications AB.
   6  *
   7  * Authors:   Bjorn Wesen
   8  *            Hans-Peter Nilsson
   9  *
  10  */
  11
  12 #include <linux/ptrace.h>
  13 #include <linux/uaccess.h>
  14 #include <linux/sched/debug.h>
  15
  16 #include <arch/sv_addr_ag.h>
  17 #include <arch/system.h>
  18
  19 void
  20 show_registers(struct pt_regs *regs)
  21 {
  22         /*
  23          * It's possible to use either the USP register or current->thread.usp.
  24          * USP might not correspond to the current process for all cases this
  25          * function is called, and current->thread.usp isn't up to date for the
  26          * current process. Experience shows that using USP is the way to go.
  27          */
  28         unsigned long usp = rdusp();
  29
  30         printk("IRP: %08lx SRP: %08lx DCCR: %08lx USP: %08lx MOF: %08lx\n",
  31                regs->irp, regs->srp, regs->dccr, usp, regs->mof);
  32
  33         printk(" r0: %08lx  r1: %08lx   r2: %08lx  r3: %08lx\n",
  34                regs->r0, regs->r1, regs->r2, regs->r3);
  35
  36         printk(" r4: %08lx  r5: %08lx   r6: %08lx  r7: %08lx\n",
  37                regs->r4, regs->r5, regs->r6, regs->r7);
  38
  39         printk(" r8: %08lx  r9: %08lx  r10: %08lx r11: %08lx\n",
  40                regs->r8, regs->r9, regs->r10, regs->r11);
  41
  42         printk("r12: %08lx r13: %08lx oR10: %08lx  sp: %08lx\n",
  43                regs->r12, regs->r13, regs->orig_r10, (long unsigned)regs);
  44
  45         printk("R_MMU_CAUSE: %08lx\n", (unsigned long)*R_MMU_CAUSE);
  46
  47         printk("Process %s (pid: %d, stackpage=%08lx)\n",
  48                current->comm, current->pid, (unsigned long)current);
  49
  50         /*
  51          * When in-kernel, we also print out the stack and code at the
  52          * time of the fault..
  53          */
  54         if (!user_mode(regs)) {
  55                 int i;
  56
  57                 show_stack(NULL, (unsigned long *)usp);
  58
  59                 /*
  60                  * If the previous stack-dump wasn't a kernel one, dump the
  61                  * kernel stack now.
  62                  */
  63                 if (usp != 0)
  64                         show_stack(NULL, NULL);
  65
  66                 printk("\nCode: ");
  67
  68                 if (regs->irp < PAGE_OFFSET)
  69                         goto bad_value;
  70
  71                 /*
  72                  * Quite often the value at regs->irp doesn't point to the
  73                  * interesting instruction, which often is the previous
  74                  * instruction. So dump at an offset large enough that the
  75                  * instruction decoding should be in sync at the interesting
  76                  * point, but small enough to fit on a row. The regs->irp
  77                  * location is pointed out in a ksymoops-friendly way by
  78                  * wrapping the byte for that address in parenthesises.
  79                  */
  80                 for (i = -12; i < 12; i++) {
  81                         unsigned char c;
  82
  83                         if (__get_user(c, &((unsigned char *)regs->irp)[i])) {
  84 bad_value:
  85                                 printk(" Bad IP value.");
  86                                 break;
  87                         }
  88
  89                         if (i == 0)
  90                                 printk("(%02x) ", c);
  91                         else
  92                                 printk("%02x ", c);
  93                 }
  94                 printk("\n");
  95         }
  96 }
  97
  98 void
  99 arch_enable_nmi(void)
 100 {
 101         asm volatile ("setf m");
 102 }
 103
 104 extern void (*nmi_handler)(struct pt_regs *);
 105 void handle_nmi(struct pt_regs *regs)
 106 {
 107         if (nmi_handler)
 108                 nmi_handler(regs);
 109
 110         /* Wait until nmi is no longer active. (We enable NMI immediately after
 111            returning from this function, and we don't want it happening while
 112            exiting from the NMI interrupt handler.) */
 113         while (*R_IRQ_MASK0_RD & IO_STATE(R_IRQ_MASK0_RD, nmi_pin, active))
 114                 ;
 115 }
 116
 117 #ifdef CONFIG_DEBUG_BUGVERBOSE
 118 void
 119 handle_BUG(struct pt_regs *regs)
 120 {
 121         struct bug_frame f;
 122         unsigned char c;
 123         unsigned long irp = regs->irp;
 124
 125         if (__copy_from_user(&f, (const void __user *)(irp - 8), sizeof f))
 126                 return;
 127         if (f.prefix != BUG_PREFIX || f.magic != BUG_MAGIC)
 128                 return;
 129         if (__get_user(c, f.filename))
 130                 f.filename = "<bad filename>";
 131
 132         printk("kernel BUG at %s:%d!\n", f.filename, f.line);
 133 }
 134 #endif