X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=kernel%2Fprintk.c;h=771f5e861bcd38af1d5d7f91666b2413b1d4008b;hb=74c37e8c9f626ed000388bebdc781a8e35ee4ab7;hp=9772b9e8feee0cb6408af2a78b04afbe55d1dbe2;hpb=0a1340c185734a57fbf4775927966ad4a1347b02;p=powerpc.git diff --git a/kernel/printk.c b/kernel/printk.c index 9772b9e8fe..771f5e861b 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -52,7 +52,7 @@ int console_printk[4] = { DEFAULT_CONSOLE_LOGLEVEL, /* default_console_loglevel */ }; -EXPORT_SYMBOL(console_printk); +EXPORT_UNUSED_SYMBOL(console_printk); /* June 2006 */ /* * Low lever drivers may need that to know if they can schedule in @@ -518,7 +518,9 @@ asmlinkage int vprintk(const char *fmt, va_list args) zap_locks(); /* This stops the holder of console_sem just where we want him */ - spin_lock_irqsave(&logbuf_lock, flags); + local_irq_save(flags); + lockdep_off(); + spin_lock(&logbuf_lock); printk_cpu = smp_processor_id(); /* Emit the output into the temporary buffer */ @@ -588,7 +590,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) */ console_locked = 1; printk_cpu = UINT_MAX; - spin_unlock_irqrestore(&logbuf_lock, flags); + spin_unlock(&logbuf_lock); /* * Console drivers may assume that per-cpu resources have @@ -604,6 +606,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) console_locked = 0; up(&console_sem); } + lockdep_on(); + local_irq_restore(flags); } else { /* * Someone else owns the drivers. We drop the spinlock, which @@ -611,7 +615,9 @@ asmlinkage int vprintk(const char *fmt, va_list args) * console drivers with the output which we just produced. */ printk_cpu = UINT_MAX; - spin_unlock_irqrestore(&logbuf_lock, flags); + spin_unlock(&logbuf_lock); + lockdep_on(); + local_irq_restore(flags); } preempt_enable(); @@ -715,6 +721,7 @@ int __init add_preferred_console(char *name, int idx, char *options) return 0; } +#ifndef CONFIG_DISABLE_CONSOLE_SUSPEND /** * suspend_console - suspend the console subsystem * @@ -722,6 +729,7 @@ int __init add_preferred_console(char *name, int idx, char *options) */ void suspend_console(void) { + printk("Suspending console(s)\n"); acquire_console_sem(); console_suspended = 1; } @@ -731,6 +739,7 @@ void resume_console(void) console_suspended = 0; release_console_sem(); } +#endif /* CONFIG_DISABLE_CONSOLE_SUSPEND */ /** * acquire_console_sem - lock the console system for exclusive use. @@ -767,7 +776,7 @@ int is_console_locked(void) { return console_locked; } -EXPORT_SYMBOL(is_console_locked); +EXPORT_UNUSED_SYMBOL(is_console_locked); /* June 2006 */ /** * release_console_sem - unlock the console system @@ -793,6 +802,9 @@ void release_console_sem(void) up(&secondary_console_sem); return; } + + console_may_schedule = 0; + for ( ; ; ) { spin_lock_irqsave(&logbuf_lock, flags); wake_klogd |= log_start - log_end; @@ -806,11 +818,17 @@ void release_console_sem(void) local_irq_restore(flags); } console_locked = 0; - console_may_schedule = 0; up(&console_sem); spin_unlock_irqrestore(&logbuf_lock, flags); - if (wake_klogd && !oops_in_progress && waitqueue_active(&log_wait)) - wake_up_interruptible(&log_wait); + if (wake_klogd && !oops_in_progress && waitqueue_active(&log_wait)) { + /* + * If we printk from within the lock dependency code, + * from within the scheduler code, then do not lock + * up due to self-recursion: + */ + if (!lockdep_internal()) + wake_up_interruptible(&log_wait); + } } EXPORT_SYMBOL(release_console_sem); @@ -1040,7 +1058,6 @@ void tty_write_message(struct tty_struct *tty, char *msg) tty->driver->write(tty, msg, strlen(msg)); return; } -EXPORT_SYMBOL_GPL(tty_write_message); /* * printk rate limiting, lifted from the networking subsystem.