x86: unify appropriate bits from dumpstack_32 and dumpstack_64

Impact: cleanup

As promised, now that dumpstack_32 and dumpstack_64 have so many bits
in common, we should merge the in-sync bits into a common file, to
prevent them from diverging again.

This patch removes bits which are common between dumpstack_32.c and
dumpstack_64.c and places them in a common dumpstack.c which is built
for both 32 and 64 bit arches.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

 Makefile       |    2
 arch/x86/kernel/Makefile       |    2
 arch/x86/kernel/Makefile       |    2
 arch/x86/kernel/Makefile       |    2
 arch/x86/kernel/Makefile       |    2
 arch/x86/kernel/Makefile       |    2
 arch/x86/kernel/dumpstack.c    |  319 +++++++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/dumpstack.h    |   39 +++++
 arch/x86/kernel/dumpstack_32.c |  294 -------------------------------------
 arch/x86/kernel/dumpstack_64.c |  285 ------------------------------------
 5 files changed, 363 insertions(+), 576 deletions(-)

1 files changed, 2 insertions, 283 deletions

diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 28c67aae5562..33ff10287a5d 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -17,19 +17,7 @@
 
 #include <asm/stacktrace.h>
 
-#define STACKSLOTS_PER_LINE 4
-#define get_bp(bp) asm("movq %%rbp, %0" : "=r" (bp) :)
-
-int panic_on_unrecovered_nmi;
-int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
-static unsigned int code_bytes = 64;
-static int die_counter;
-
-void printk_address(unsigned long address, int reliable)
-{
-        printk(" [<%p>] %s%pS\n", (void *) address,
-                        reliable ? "" : "? ", (void *) address);
-}
+#include "dumpstack.h"
 
 static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
                                         unsigned *usedp, char **idp)
@@ -113,51 +101,6 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
  * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
  */
 
-static inline int valid_stack_ptr(struct thread_info *tinfo,
-                        void *p, unsigned int size, void *end)
-{
-        void *t = tinfo;
-        if (end) {
-                if (p < end && p >= (end-THREAD_SIZE))
-                        return 1;
-                else
-                        return 0;
-        }
-        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,
-                unsigned long *end)
-{
-        struct stack_frame *frame = (struct stack_frame *)bp;
-
-        while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
-                unsigned long addr;
-
-                addr = *stack;
-                if (__kernel_text_address(addr)) {
-                        if ((unsigned long) stack == bp + sizeof(long)) {
-                                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)
@@ -248,57 +191,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
 }
 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)
-{
-        printk("%s <%s> ", (char *)data, name);
-        return 0;
-}
-
-/*
- * Print one address/symbol entries per line.
- */
-static void print_trace_address(void *data, unsigned long addr, int reliable)
-{
-        touch_nmi_watchdog();
-        printk(data);
-        printk_address(addr, reliable);
-}
-
-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)
-{
-        printk("%sCall Trace:\n", log_lvl);
-        dump_trace(task, regs, stack, bp, &print_trace_ops, 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
+void
 show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
                 unsigned long *sp, unsigned long bp, char *log_lvl)
 {
@@ -342,33 +235,6 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
         show_trace_log_lvl(task, regs, sp, bp, log_lvl);
 }
 
-void show_stack(struct task_struct *task, unsigned long *sp)
-{
-        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)
-                get_bp(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(NULL, NULL, &stack, bp);
-}
-EXPORT_SYMBOL(dump_stack);
-
 void show_registers(struct pt_regs *regs)
 {
         int i;
@@ -429,150 +295,3 @@ int is_valid_bugaddr(unsigned long ip)
         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)
-{
-        int cpu;
-        unsigned long flags;
-
-        oops_enter();
-
-        /* racy, but better than risking deadlock. */
-        raw_local_irq_save(flags);
-        cpu = smp_processor_id();
-        if (!__raw_spin_trylock(&die_lock)) {
-                if (cpu == die_owner)
-                        /* nested oops. should stop eventually */;
-                else
-                        __raw_spin_lock(&die_lock);
-        }
-        die_nest_count++;
-        die_owner = cpu;
-        console_verbose();
-        bust_spinlocks(1);
-        return flags;
-}
-
-void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
-{
-        if (regs && kexec_should_crash(current))
-                crash_kexec(regs);
-
-        bust_spinlocks(0);
-        die_owner = -1;
-        add_taint(TAINT_DIE);
-        die_nest_count--;
-        if (!die_nest_count)
-                /* Nest count reaches zero, release the lock. */
-                __raw_spin_unlock(&die_lock);
-        raw_local_irq_restore(flags);
-        oops_exit();
-
-        if (!signr)
-                return;
-        if (in_interrupt())
-                panic("Fatal exception in interrupt");
-        if (panic_on_oops)
-                panic("Fatal exception");
-        do_exit(signr);
-}
-
-int __kprobes __die(const char *str, struct pt_regs *regs, long err)
-{
-        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");
-        sysfs_printk_last_file();
-        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 */
-        printk(KERN_ALERT "RIP ");
-        printk_address(regs->ip, 1);
-        printk(" RSP <%016lx>\n", regs->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();
-        int sig = SIGSEGV;
-
-        if (!user_mode_vm(regs))
-                report_bug(regs->ip, regs);
-
-        if (__die(str, regs, err))
-                sig = 0;
-        oops_end(flags, regs, sig);
-}
-
-void notrace __kprobes
-die_nmi(char *str, struct pt_regs *regs, int do_panic)
-{
-        unsigned long flags;
-
-        if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
-                return;
-
-        /*
-         * We are in trouble anyway, lets at least try
-         * to get a message out.
-         */
-        flags = oops_begin();
-        printk(KERN_EMERG "%s", str);
-        printk(" on CPU%d, ip %08lx, registers:\n",
-                smp_processor_id(), regs->ip);
-        show_registers(regs);
-        oops_end(flags, regs, 0);
-        if (do_panic || panic_on_oops)
-                panic("Non maskable interrupt");
-        nmi_exit();
-        local_irq_enable();
-        do_exit(SIGBUS);
-}
-
-static int __init oops_setup(char *s)
-{
-        if (!s)
-                return -EINVAL;
-        if (!strcmp(s, "panic"))
-                panic_on_oops = 1;
-        return 0;
-}
-early_param("oops", oops_setup);
-
-static int __init kstack_setup(char *s)
-{
-        if (!s)
-                return -EINVAL;
-        kstack_depth_to_print = simple_strtoul(s, NULL, 0);
-        return 0;
-}
-early_param("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);