--- /dev/null
+/*
+ * linux/arch/unicore32/kernel/traps.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 'traps.c' handles hardware exceptions after we have saved some state.
+ * Mostly a debugging aid, but will probably kill the offending process.
+ */
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/spinlock.h>
+#include <linux/personality.h>
+#include <linux/kallsyms.h>
+#include <linux/kdebug.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include <linux/hardirq.h>
+#include <linux/init.h>
+#include <linux/atomic.h>
+#include <linux/unistd.h>
+
+#include <asm/cacheflush.h>
+#include <asm/traps.h>
+
+#include "setup.h"
+
+static void dump_mem(const char *, const char *, unsigned long, unsigned long);
+
+void dump_backtrace_entry(unsigned long where,
+ unsigned long from, unsigned long frame)
+{
+#ifdef CONFIG_KALLSYMS
+ printk(KERN_DEFAULT "[<%08lx>] (%pS) from [<%08lx>] (%pS)\n",
+ where, (void *)where, from, (void *)from);
+#else
+ printk(KERN_DEFAULT "Function entered at [<%08lx>] from [<%08lx>]\n",
+ where, from);
+#endif
+}
+
+/*
+ * Stack pointers should always be within the kernels view of
+ * physical memory. If it is not there, then we can't dump
+ * out any information relating to the stack.
+ */
+static int verify_stack(unsigned long sp)
+{
+ if (sp < PAGE_OFFSET ||
+ (sp > (unsigned long)high_memory && high_memory != NULL))
+ return -EFAULT;
+
+ return 0;
+}
+
+/*
+ * Dump out the contents of some memory nicely...
+ */
+static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
+ unsigned long top)
+{
+ unsigned long first;
+ mm_segment_t fs;
+ int i;
+
+ /*
+ * We need to switch to kernel mode so that we can use __get_user
+ * to safely read from kernel space. Note that we now dump the
+ * code first, just in case the backtrace kills us.
+ */
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ printk(KERN_DEFAULT "%s%s(0x%08lx to 0x%08lx)\n",
+ lvl, str, bottom, top);
+
+ for (first = bottom & ~31; first < top; first += 32) {
+ unsigned long p;
+ char str[sizeof(" 12345678") * 8 + 1];
+
+ memset(str, ' ', sizeof(str));
+ str[sizeof(str) - 1] = '\0';
+
+ for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
+ if (p >= bottom && p < top) {
+ unsigned long val;
+ if (__get_user(val, (unsigned long *)p) == 0)
+ sprintf(str + i * 9, " %08lx", val);
+ else
+ sprintf(str + i * 9, " ????????");
+ }
+ }
+ printk(KERN_DEFAULT "%s%04lx:%s\n", lvl, first & 0xffff, str);
+ }
+
+ set_fs(fs);
+}
+
+static void dump_instr(const char *lvl, struct pt_regs *regs)
+{
+ unsigned long addr = instruction_pointer(regs);
+ const int width = 8;
+ mm_segment_t fs;
+ char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
+ int i;
+
+ /*
+ * We need to switch to kernel mode so that we can use __get_user
+ * to safely read from kernel space. Note that we now dump the
+ * code first, just in case the backtrace kills us.
+ */
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ for (i = -4; i < 1; i++) {
+ unsigned int val, bad;
+
+ bad = __get_user(val, &((u32 *)addr)[i]);
+
+ if (!bad)
+ p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ",
+ width, val);
+ else {
+ p += sprintf(p, "bad PC value");
+ break;
+ }
+ }
+ printk(KERN_DEFAULT "%sCode: %s\n", lvl, str);
+
+ set_fs(fs);
+}
+
+static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
+{
+ unsigned int fp, mode;
+ int ok = 1;
+
+ printk(KERN_DEFAULT "Backtrace: ");
+
+ if (!tsk)
+ tsk = current;
+
+ if (regs) {
+ fp = regs->UCreg_fp;
+ mode = processor_mode(regs);
+ } else if (tsk != current) {
+ fp = thread_saved_fp(tsk);
+ mode = 0x10;
+ } else {
+ asm("mov %0, fp" : "=r" (fp) : : "cc");
+ mode = 0x10;
+ }
+
+ if (!fp) {
+ printk("no frame pointer");
+ ok = 0;
+ } else if (verify_stack(fp)) {
+ printk("invalid frame pointer 0x%08x", fp);
+ ok = 0;
+ } else if (fp < (unsigned long)end_of_stack(tsk))
+ printk("frame pointer underflow");
+ printk("\n");
+
+ if (ok)
+ c_backtrace(fp, mode);
+}
+
+void show_stack(struct task_struct *tsk, unsigned long *sp)
+{
+ dump_backtrace(NULL, tsk);
+ barrier();
+}
+
+static int __die(const char *str, int err, struct thread_info *thread,
+ struct pt_regs *regs)
+{
+ struct task_struct *tsk = thread->task;
+ static int die_counter;
+ int ret;
+
+ printk(KERN_EMERG "Internal error: %s: %x [#%d]\n",
+ str, err, ++die_counter);
+
+ /* trap and error numbers are mostly meaningless on UniCore */
+ ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, \
+ SIGSEGV);
+ if (ret == NOTIFY_STOP)
+ return ret;
+
+ print_modules();
+ __show_regs(regs);
+ printk(KERN_EMERG "Process %.*s (pid: %d, stack limit = 0x%p)\n",
+ TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
+
+ if (!user_mode(regs) || in_interrupt()) {
+ dump_mem(KERN_EMERG, "Stack: ", regs->UCreg_sp,
+ THREAD_SIZE + (unsigned long)task_stack_page(tsk));
+ dump_backtrace(regs, tsk);
+ dump_instr(KERN_EMERG, regs);
+ }
+
+ return ret;
+}
+
+DEFINE_SPINLOCK(die_lock);
+
+/*
+ * This function is protected against re-entrancy.
+ */
+void die(const char *str, struct pt_regs *regs, int err)
+{
+ struct thread_info *thread = current_thread_info();
+ int ret;
+
+ oops_enter();
+
+ spin_lock_irq(&die_lock);
+ console_verbose();
+ bust_spinlocks(1);
+ ret = __die(str, err, thread, regs);
+
+ bust_spinlocks(0);
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+ spin_unlock_irq(&die_lock);
+ oops_exit();
+
+ if (in_interrupt())
+ panic("Fatal exception in interrupt");
+ if (panic_on_oops)
+ panic("Fatal exception");
+ if (ret != NOTIFY_STOP)
+ do_exit(SIGSEGV);
+}
+
+void uc32_notify_die(const char *str, struct pt_regs *regs,
+ struct siginfo *info, unsigned long err, unsigned long trap)
+{
+ if (user_mode(regs)) {
+ current->thread.error_code = err;
+ current->thread.trap_no = trap;
+
+ force_sig_info(info->si_signo, info, current);
+ } else
+ die(str, regs, err);
+}
+
+/*
+ * bad_mode handles the impossible case in the vectors. If you see one of
+ * these, then it's extremely serious, and could mean you have buggy hardware.
+ * It never returns, and never tries to sync. We hope that we can at least
+ * dump out some state information...
+ */
+asmlinkage void bad_mode(struct pt_regs *regs, unsigned int reason)
+{
+ console_verbose();
+
+ printk(KERN_CRIT "Bad mode detected with reason 0x%x\n", reason);
+
+ die("Oops - bad mode", regs, 0);
+ local_irq_disable();
+ panic("bad mode");
+}
+
+void __pte_error(const char *file, int line, unsigned long val)
+{
+ printk(KERN_DEFAULT "%s:%d: bad pte %08lx.\n", file, line, val);
+}
+
+void __pmd_error(const char *file, int line, unsigned long val)
+{
+ printk(KERN_DEFAULT "%s:%d: bad pmd %08lx.\n", file, line, val);
+}
+
+void __pgd_error(const char *file, int line, unsigned long val)
+{
+ printk(KERN_DEFAULT "%s:%d: bad pgd %08lx.\n", file, line, val);
+}
+
+asmlinkage void __div0(void)
+{
+ printk(KERN_DEFAULT "Division by zero in kernel.\n");
+ dump_stack();
+}
+EXPORT_SYMBOL(__div0);
+
+void abort(void)
+{
+ BUG();
+
+ /* if that doesn't kill us, halt */
+ panic("Oops failed to kill thread");
+}
+EXPORT_SYMBOL(abort);
+
+void __init trap_init(void)
+{
+ return;
+}
+
+void __init early_trap_init(void)
+{
+ unsigned long vectors = VECTORS_BASE;
+
+ /*
+ * Copy the vectors, stubs (in entry-unicore.S)
+ * into the vector page, mapped at 0xffff0000, and ensure these
+ * are visible to the instruction stream.
+ */
+ memcpy((void *)vectors,
+ __vectors_start,
+ __vectors_end - __vectors_start);
+ memcpy((void *)vectors + 0x200,
+ __stubs_start,
+ __stubs_end - __stubs_start);
+
+ early_signal_init();
+
+ flush_icache_range(vectors, vectors + PAGE_SIZE);
+}
Code Review / kvmfornfv.git / blobdiff