static inline void pmac_backlight_unblank(void) { }
#endif
-int die(const char *str, struct pt_regs *regs, long err)
+static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;
+static int die_owner = -1;
+static unsigned int die_nest_count;
+static int die_counter;
+
+static unsigned __kprobes long oops_begin(struct pt_regs *regs)
{
- static struct {
- raw_spinlock_t lock;
- u32 lock_owner;
- int lock_owner_depth;
- } die = {
- .lock = __RAW_SPIN_LOCK_UNLOCKED(die.lock),
- .lock_owner = -1,
- .lock_owner_depth = 0
- };
- static int die_counter;
+ int cpu;
unsigned long flags;
if (debugger(regs))
oops_enter();
- if (die.lock_owner != raw_smp_processor_id()) {
- console_verbose();
- raw_spin_lock_irqsave(&die.lock, flags);
- die.lock_owner = smp_processor_id();
- die.lock_owner_depth = 0;
- bust_spinlocks(1);
- if (machine_is(powermac))
- pmac_backlight_unblank();
- } else {
- local_save_flags(flags);
+ /* racy, but better than risking deadlock. */
+ raw_local_irq_save(flags);
+ cpu = smp_processor_id();
+ if (!arch_spin_trylock(&die_lock)) {
+ if (cpu == die_owner)
+ /* nested oops. should stop eventually */;
+ else
+ arch_spin_lock(&die_lock);
}
+ die_nest_count++;
+ die_owner = cpu;
+ console_verbose();
+ bust_spinlocks(1);
+ if (machine_is(powermac))
+ pmac_backlight_unblank();
+ return flags;
+}
- if (++die.lock_owner_depth < 3) {
- printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
-#ifdef CONFIG_PREEMPT
- printk("PREEMPT ");
-#endif
-#ifdef CONFIG_SMP
- printk("SMP NR_CPUS=%d ", NR_CPUS);
-#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
- printk("DEBUG_PAGEALLOC ");
-#endif
-#ifdef CONFIG_NUMA
- printk("NUMA ");
-#endif
- printk("%s\n", ppc_md.name ? ppc_md.name : "");
+static void __kprobes oops_end(unsigned long flags, struct pt_regs *regs,
+ int signr)
+{
+ bust_spinlocks(0);
+ die_owner = -1;
+ add_taint(TAINT_DIE);
+ die_nest_count--;
+ oops_exit();
+ printk("\n");
+ if (!die_nest_count)
+ /* Nest count reaches zero, release the lock. */
+ arch_spin_unlock(&die_lock);
+ raw_local_irq_restore(flags);
- if (notify_die(DIE_OOPS, str, regs, err, 255,
- SIGSEGV) == NOTIFY_STOP)
- return 1;
+ /*
+ * A system reset (0x100) is a request to dump, so we always send
+ * it through the crashdump code.
+ */
+ if (kexec_should_crash(current) || (TRAP(regs) == 0x100)) {
+ crash_kexec(regs);
- print_modules();
- show_regs(regs);
- } else {
- printk("Recursive die() failure, output suppressed\n");
+ /*
+ * We aren't the primary crash CPU. We need to send it
+ * to a holding pattern to avoid it ending up in the panic
+ * code.
+ */
+ crash_kexec_secondary(regs);
}
- bust_spinlocks(0);
- die.lock_owner = -1;
- add_taint(TAINT_DIE);
- raw_spin_unlock_irqrestore(&die.lock, flags);
+ if (!signr)
+ return;
- if (kexec_should_crash(current) ||
- kexec_sr_activated(smp_processor_id()))
- crash_kexec(regs);
- crash_kexec_secondary(regs);
+ /*
+ * While our oops output is serialised by a spinlock, output
+ * from panic() called below can race and corrupt it. If we
+ * know we are going to panic, delay for 1 second so we have a
+ * chance to get clean backtraces from all CPUs that are oopsing.
+ */
+ if (in_interrupt() || panic_on_oops || !current->pid ||
+ is_global_init(current)) {
+ mdelay(MSEC_PER_SEC);
+ }
if (in_interrupt())
panic("Fatal exception in interrupt");
-
if (panic_on_oops)
panic("Fatal exception");
+ do_exit(signr);
+}
- oops_exit();
- do_exit(err);
+static int __kprobes __die(const char *str, struct pt_regs *regs, long err)
+{
+ printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
+#ifdef CONFIG_PREEMPT
+ printk("PREEMPT ");
+#endif
+#ifdef CONFIG_SMP
+ printk("SMP NR_CPUS=%d ", NR_CPUS);
+#endif
+#ifdef CONFIG_DEBUG_PAGEALLOC
+ printk("DEBUG_PAGEALLOC ");
+#endif
+#ifdef CONFIG_NUMA
+ printk("NUMA ");
+#endif
+ printk("%s\n", ppc_md.name ? ppc_md.name : "");
+
+ if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV) == NOTIFY_STOP)
+ return 1;
+
+ print_modules();
+ show_regs(regs);
return 0;
}
+void die(const char *str, struct pt_regs *regs, long err)
+{
+ unsigned long flags = oops_begin(regs);
+
+ if (__die(str, regs, err))
+ err = 0;
+ oops_end(flags, regs, err);
+}
+
void user_single_step_siginfo(struct task_struct *tsk,
struct pt_regs *regs, siginfo_t *info)
{
"at %016lx nip %016lx lr %016lx code %x\n";
if (!user_mode(regs)) {
- if (die("Exception in kernel mode", regs, signr))
- return;
- } else if (show_unhandled_signals &&
- unhandled_signal(current, signr)) {
+ die("Exception in kernel mode", regs, signr);
+ return;
+ }
+
+ if (show_unhandled_signals && unhandled_signal(current, signr)) {
printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
current->comm, current->pid, signr,
addr, regs->nip, regs->link, code);
return;
}
-#ifdef CONFIG_KEXEC
- cpumask_set_cpu(smp_processor_id(), &cpus_in_sr);
-#endif
-
die("System Reset", regs, SIGABRT);
- /*
- * Some CPUs when released from the debugger will execute this path.
- * These CPUs entered the debugger via a soft-reset. If the CPU was
- * hung before entering the debugger it will return to the hung
- * state when exiting this function. This causes a problem in
- * kdump since the hung CPU(s) will not respond to the IPI sent
- * from kdump. To prevent the problem we call crash_kexec_secondary()
- * here. If a kdump had not been initiated or we exit the debugger
- * with the "exit and recover" command (x) crash_kexec_secondary()
- * will return after 5ms and the CPU returns to its previous state.
- */
- crash_kexec_secondary(regs);
-
/* Must die if the interrupt is not recoverable */
if (!(regs->msr & MSR_RI))
panic("Unrecoverable System Reset");
projects / linux-imx.git / blobdiff