/*
* Stack dumping functions
*
* Copyright IBM Corp. 1999, 2013
*/
#include <linux/kallsyms.h>
#include <linux/hardirq.h>
#include <linux/kprobes.h>
#include <linux/utsname.h>
#include <linux/export.h>
#include <linux/kdebug.h>
#include <linux/ptrace.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <asm/processor.h>
#include <asm/debug.h>
#include <asm/dis.h>
#include <asm/ipl.h>
#ifndef CONFIG_64BIT
#define LONG "%08lx "
#define FOURLONG "%08lx %08lx %08lx %08lx\n"
static int kstack_depth_to_print = 12;
#else /* CONFIG_64BIT */
#define LONG "%016lx "
#define FOURLONG "%016lx %016lx %016lx %016lx\n"
static int kstack_depth_to_print = 20;
#endif /* CONFIG_64BIT */
/*
* For show_trace we have tree different stack to consider:
* - the panic stack which is used if the kernel stack has overflown
* - the asynchronous interrupt stack (cpu related)
* - the synchronous kernel stack (process related)
* The stack trace can start at any of the three stack and can potentially
* touch all of them. The order is: panic stack, async stack, sync stack.
*/
static unsigned long
__show_trace(unsigned long sp, unsigned long low, unsigned long high)
{
struct stack_frame *sf;
struct pt_regs *regs;
unsigned long addr;
while (1) {
sp = sp & PSW_ADDR_INSN;
if (sp < low || sp > high - sizeof(*sf))
return sp;
sf = (struct stack_frame *) sp;
addr = sf->gprs[8] & PSW_ADDR_INSN;
printk("([<%016lx>] %pSR)\n", addr, (void *)addr);
/* Follow the backchain. */
while (1) {
low = sp;
sp = sf->back_chain & PSW_ADDR_INSN;
if (!sp)
break;
if (sp <= low || sp > high - sizeof(*sf))
return sp;
sf = (struct stack_frame *) sp;
addr = sf->gprs[8] & PSW_ADDR_INSN;
printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
}
/* Zero backchain detected, check for interrupt frame. */
sp = (unsigned long) (sf + 1);
if (sp <= low || sp > high - sizeof(*regs))
return sp;
regs = (struct pt_regs *) sp;
addr = regs->psw.addr & PSW_ADDR_INSN;
printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
low = sp;
sp = regs->gprs[15];
}
}
static void show_trace(struct task_struct *task, unsigned long *stack)
{
const unsigned long frame_size =
STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
register unsigned long __r15 asm ("15");
unsigned long sp;
sp = (unsigned long) stack;
if (!sp)
sp = task ? task->thread.ksp : __r15;
printk("Call Trace:\n");
#ifdef CONFIG_CHECK_STACK
sp = __show_trace(sp,
S390_lowcore.panic_stack + frame_size - 4096,
S390_lowcore.panic_stack + frame_size);
#endif
sp = __show_trace(sp,
S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
S390_lowcore.async_stack + frame_size);
if (task)
__show_trace(sp, (unsigned long) task_stack_page(task),
(unsigned long) task_stack_page(task) + THREAD_SIZE);
else
__show_trace(sp, S390_lowcore.thread_info,
S390_lowcore.thread_info + THREAD_SIZE);
if (!task)
task = current;
debug_show_held_locks(task);
}
void show_stack(struct task_struct *task, unsigned long *sp)
{
register unsigned long *__r15 asm ("15");
unsigned long *stack;
int i;
if (!sp)
stack = task ? (unsigned long *) task->thread.ksp : __r15;
else
stack = sp;
for (i = 0; i < kstack_depth_to_print; i++) {
if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
break;
if ((i * sizeof(long) % 32) == 0)
printk("%s ", i == 0 ? "" : "\n");
printk(LONG, *stack++);
}
printk("\n");
show_trace(task, sp);
}
static void show_last_breaking_event(struct pt_regs *regs)
{
#ifdef CONFIG_64BIT
printk("Last Breaking-Event-Address:\n");
printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
#endif
}
static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
{
return (regs->psw.mask & bits) / ((~bits + 1) & bits);
}
void show_registers(struct pt_regs *regs)
{
char *mode;
mode = user_mode(regs) ? "User" : "Krnl";
printk("%s PSW : %p %p", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
if (!user_mode(regs))
printk(" (%pSR)", (void *)regs->psw.addr);
printk("\n");
printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
"P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
#ifdef CONFIG_64BIT
printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));
#endif
printk("\n%s GPRS: " FOURLONG, mode,
regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
printk(" " FOURLONG,
regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
printk(" " FOURLONG,
regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
printk(" " FOURLONG,
regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
show_code(regs);
}
void show_regs(struct pt_regs *regs)
{
show_regs_print_info(KERN_DEFAULT);
show_registers(regs);
/* Show stack backtrace if pt_regs is from kernel mode */
if (!user_mode(regs))
show_trace(NULL, (unsigned long *) regs->gprs[15]);
show_last_breaking_event(regs);
}
static DEFINE_SPINLOCK(die_lock);
void die(struct pt_regs *regs, const char *str)
{
static int die_counter;
oops_enter();
lgr_info_log();
debug_stop_all();
console_verbose();
spin_lock_irq(&die_lock);
bust_spinlocks(1);
printk("%s: %04x [#%d] ", str, regs->int_code & 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");
notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
print_modules();
show_regs(regs);
bust_spinlocks(0);
add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
spin_unlock_irq(&die_lock);
if (in_interrupt())
panic("Fatal exception in interrupt");
if (panic_on_oops)
panic("Fatal exception: panic_on_oops");
oops_exit();
do_exit(SIGSEGV);
}
