i386: split out dumpstack code from traps_32.c
The dumpstack code is logically quite independent from the
hardware traps. Split it out into its own file.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
new file mode 100644
index 0000000..c398b27
--- /dev/null
+++ b/arch/x86/kernel/dumpstack_32.c
@@ -0,0 +1,422 @@
+/*
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
+ */
+#include <linux/kallsyms.h>
+#include <linux/kprobes.h>
+#include <linux/uaccess.h>
+#include <linux/utsname.h>
+#include <linux/hardirq.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+#include <linux/kexec.h>
+#include <linux/bug.h>
+#include <linux/nmi.h>
+
+#include <asm/stacktrace.h>
+
+int panic_on_unrecovered_nmi;
+int kstack_depth_to_print = 24;
+static unsigned int code_bytes = 64;
+static int die_counter;
+
+void printk_address(unsigned long address, int reliable)
+{
+#ifdef CONFIG_KALLSYMS
+ unsigned long offset = 0;
+ unsigned long symsize;
+ const char *symname;
+ char *modname;
+ char *delim = ":";
+ char namebuf[KSYM_NAME_LEN];
+ char reliab[4] = "";
+
+ symname = kallsyms_lookup(address, &symsize, &offset,
+ &modname, namebuf);
+ if (!symname) {
+ printk(" [<%08lx>]\n", address);
+ return;
+ }
+ if (!reliable)
+ strcpy(reliab, "? ");
+
+ if (!modname)
+ modname = delim = "";
+ printk(" [<%08lx>] %s%s%s%s%s+0x%lx/0x%lx\n",
+ address, reliab, delim, modname, delim, symname, offset, symsize);
+#else
+ printk(" [<%08lx>]\n", address);
+#endif
+}
+
+static inline int valid_stack_ptr(struct thread_info *tinfo,
+ void *p, unsigned int size)
+{
+ void *t = tinfo;
+ return p > t && p <= t + THREAD_SIZE - size;
+}
+
+/* The form of the top of the frame on the stack */
+struct stack_frame {
+ struct stack_frame *next_frame;
+ unsigned long return_address;
+};
+
+static inline unsigned long
+print_context_stack(struct thread_info *tinfo,
+ unsigned long *stack, unsigned long bp,
+ const struct stacktrace_ops *ops, void *data)
+{
+ struct stack_frame *frame = (struct stack_frame *)bp;
+
+ while (valid_stack_ptr(tinfo, stack, sizeof(*stack))) {
+ unsigned long addr;
+
+ addr = *stack;
+ if (__kernel_text_address(addr)) {
+ if ((unsigned long) stack == bp + 4) {
+ ops->address(data, addr, 1);
+ frame = frame->next_frame;
+ bp = (unsigned long) frame;
+ } else {
+ ops->address(data, addr, bp == 0);
+ }
+ }
+ stack++;
+ }
+ return bp;
+}
+
+void dump_trace(struct task_struct *task, struct pt_regs *regs,
+ unsigned long *stack, unsigned long bp,
+ const struct stacktrace_ops *ops, void *data)
+{
+ if (!task)
+ task = current;
+
+ if (!stack) {
+ unsigned long dummy;
+ stack = &dummy;
+ if (task != current)
+ stack = (unsigned long *)task->thread.sp;
+ }
+
+#ifdef CONFIG_FRAME_POINTER
+ if (!bp) {
+ if (task == current) {
+ /* Grab bp right from our regs */
+ asm("movl %%ebp, %0" : "=r" (bp) :);
+ } else {
+ /* bp is the last reg pushed by switch_to */
+ bp = *(unsigned long *) task->thread.sp;
+ }
+ }
+#endif
+
+ for (;;) {
+ struct thread_info *context;
+
+ context = (struct thread_info *)
+ ((unsigned long)stack & (~(THREAD_SIZE - 1)));
+ bp = print_context_stack(context, stack, bp, ops, data);
+ /*
+ * Should be after the line below, but somewhere
+ * in early boot context comes out corrupted and we
+ * can't reference it:
+ */
+ if (ops->stack(data, "IRQ") < 0)
+ break;
+ stack = (unsigned long *)context->previous_esp;
+ if (!stack)
+ break;
+ touch_nmi_watchdog();
+ }
+}
+EXPORT_SYMBOL(dump_trace);
+
+static void
+print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
+{
+ printk(data);
+ print_symbol(msg, symbol);
+ printk("\n");
+}
+
+static void print_trace_warning(void *data, char *msg)
+{
+ printk("%s%s\n", (char *)data, msg);
+}
+
+static int print_trace_stack(void *data, char *name)
+{
+ return 0;
+}
+
+/*
+ * Print one address/symbol entries per line.
+ */
+static void print_trace_address(void *data, unsigned long addr, int reliable)
+{
+ printk("%s [<%08lx>] ", (char *)data, addr);
+ if (!reliable)
+ printk("? ");
+ print_symbol("%s\n", addr);
+ touch_nmi_watchdog();
+}
+
+static const struct stacktrace_ops print_trace_ops = {
+ .warning = print_trace_warning,
+ .warning_symbol = print_trace_warning_symbol,
+ .stack = print_trace_stack,
+ .address = print_trace_address,
+};
+
+static void
+show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
+ unsigned long *stack, unsigned long bp, char *log_lvl)
+{
+ dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
+ printk("%s =======================\n", log_lvl);
+}
+
+void show_trace(struct task_struct *task, struct pt_regs *regs,
+ unsigned long *stack, unsigned long bp)
+{
+ show_trace_log_lvl(task, regs, stack, bp, "");
+}
+
+static void
+show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
+ unsigned long *sp, unsigned long bp, char *log_lvl)
+{
+ unsigned long *stack;
+ int i;
+
+ if (sp == NULL) {
+ if (task)
+ sp = (unsigned long *)task->thread.sp;
+ else
+ sp = (unsigned long *)&sp;
+ }
+
+ stack = sp;
+ for (i = 0; i < kstack_depth_to_print; i++) {
+ if (kstack_end(stack))
+ break;
+ if (i && ((i % 8) == 0))
+ printk("\n%s ", log_lvl);
+ printk("%08lx ", *stack++);
+ }
+ printk("\n%sCall Trace:\n", log_lvl);
+
+ show_trace_log_lvl(task, regs, sp, bp, log_lvl);
+}
+
+void show_stack(struct task_struct *task, unsigned long *sp)
+{
+ printk(" ");
+ show_stack_log_lvl(task, NULL, sp, 0, "");
+}
+
+/*
+ * The architecture-independent dump_stack generator
+ */
+void dump_stack(void)
+{
+ unsigned long bp = 0;
+ unsigned long stack;
+
+#ifdef CONFIG_FRAME_POINTER
+ if (!bp)
+ asm("movl %%ebp, %0" : "=r" (bp):);
+#endif
+
+ printk("Pid: %d, comm: %.20s %s %s %.*s\n",
+ current->pid, current->comm, print_tainted(),
+ init_utsname()->release,
+ (int)strcspn(init_utsname()->version, " "),
+ init_utsname()->version);
+
+ show_trace(current, NULL, &stack, bp);
+}
+
+EXPORT_SYMBOL(dump_stack);
+
+void show_registers(struct pt_regs *regs)
+{
+ int i;
+
+ print_modules();
+ __show_regs(regs, 0);
+
+ printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
+ TASK_COMM_LEN, current->comm, task_pid_nr(current),
+ current_thread_info(), current, task_thread_info(current));
+ /*
+ * When in-kernel, we also print out the stack and code at the
+ * time of the fault..
+ */
+ if (!user_mode_vm(regs)) {
+ unsigned int code_prologue = code_bytes * 43 / 64;
+ unsigned int code_len = code_bytes;
+ unsigned char c;
+ u8 *ip;
+
+ printk("\n" KERN_EMERG "Stack: ");
+ show_stack_log_lvl(NULL, regs, ®s->sp, 0, KERN_EMERG);
+
+ printk(KERN_EMERG "Code: ");
+
+ ip = (u8 *)regs->ip - code_prologue;
+ if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
+ /* try starting at EIP */
+ ip = (u8 *)regs->ip;
+ code_len = code_len - code_prologue + 1;
+ }
+ for (i = 0; i < code_len; i++, ip++) {
+ if (ip < (u8 *)PAGE_OFFSET ||
+ probe_kernel_address(ip, c)) {
+ printk(" Bad EIP value.");
+ break;
+ }
+ if (ip == (u8 *)regs->ip)
+ printk("<%02x> ", c);
+ else
+ printk("%02x ", c);
+ }
+ }
+ printk("\n");
+}
+
+int is_valid_bugaddr(unsigned long ip)
+{
+ unsigned short ud2;
+
+ if (ip < PAGE_OFFSET)
+ return 0;
+ if (probe_kernel_address((unsigned short *)ip, ud2))
+ return 0;
+
+ return ud2 == 0x0b0f;
+}
+
+static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
+static int die_owner = -1;
+static unsigned int die_nest_count;
+
+unsigned __kprobes long oops_begin(void)
+{
+ unsigned long flags;
+
+ oops_enter();
+
+ if (die_owner != raw_smp_processor_id()) {
+ console_verbose();
+ raw_local_irq_save(flags);
+ __raw_spin_lock(&die_lock);
+ die_owner = smp_processor_id();
+ die_nest_count = 0;
+ bust_spinlocks(1);
+ } else {
+ raw_local_irq_save(flags);
+ }
+ die_nest_count++;
+ return flags;
+}
+
+void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
+{
+ bust_spinlocks(0);
+ die_owner = -1;
+ add_taint(TAINT_DIE);
+ __raw_spin_unlock(&die_lock);
+ raw_local_irq_restore(flags);
+
+ if (!regs)
+ return;
+
+ if (kexec_should_crash(current))
+ crash_kexec(regs);
+
+ if (in_interrupt())
+ panic("Fatal exception in interrupt");
+
+ if (panic_on_oops)
+ panic("Fatal exception");
+
+ oops_exit();
+ do_exit(signr);
+}
+
+int __kprobes __die(const char *str, struct pt_regs *regs, long err)
+{
+ unsigned short ss;
+ unsigned long sp;
+
+ printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
+#ifdef CONFIG_PREEMPT
+ printk("PREEMPT ");
+#endif
+#ifdef CONFIG_SMP
+ printk("SMP ");
+#endif
+#ifdef CONFIG_DEBUG_PAGEALLOC
+ printk("DEBUG_PAGEALLOC");
+#endif
+ printk("\n");
+ if (notify_die(DIE_OOPS, str, regs, err,
+ current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
+ return 1;
+
+ show_registers(regs);
+ /* Executive summary in case the oops scrolled away */
+ sp = (unsigned long) (®s->sp);
+ savesegment(ss, ss);
+ if (user_mode(regs)) {
+ sp = regs->sp;
+ ss = regs->ss & 0xffff;
+ }
+ printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
+ print_symbol("%s", regs->ip);
+ printk(" SS:ESP %04x:%08lx\n", ss, sp);
+ return 0;
+}
+
+/*
+ * This is gone through when something in the kernel has done something bad
+ * and is about to be terminated:
+ */
+void die(const char *str, struct pt_regs *regs, long err)
+{
+ unsigned long flags = oops_begin();
+
+ if (die_nest_count < 3) {
+ report_bug(regs->ip, regs);
+
+ if (__die(str, regs, err))
+ regs = NULL;
+ } else {
+ printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
+ }
+
+ oops_end(flags, regs, SIGSEGV);
+}
+
+static int __init kstack_setup(char *s)
+{
+ kstack_depth_to_print = simple_strtoul(s, NULL, 0);
+
+ return 1;
+}
+__setup("kstack=", kstack_setup);
+
+static int __init code_bytes_setup(char *s)
+{
+ code_bytes = simple_strtoul(s, NULL, 0);
+ if (code_bytes > 8192)
+ code_bytes = 8192;
+
+ return 1;
+}
+__setup("code_bytes=", code_bytes_setup);