diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index f426a2b12a9b..e17d384f8c6b 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1557,28 +1557,6 @@ static void call_console_drivers(int level, } } -/* - * Zap console related locks when oopsing. - * To leave time for slow consoles to print a full oops, - * only zap at most once every 30 seconds. - */ -static void zap_locks(void) -{ - static unsigned long oops_timestamp; - - if (time_after_eq(jiffies, oops_timestamp) && - !time_after(jiffies, oops_timestamp + 30 * HZ)) - return; - - oops_timestamp = jiffies; - - debug_locks_off(); - /* If a crash is occurring, make sure we can't deadlock */ - raw_spin_lock_init(&logbuf_lock); - /* And make sure that we print immediately */ - sema_init(&console_sem, 1); -} - int printk_delay_msec __read_mostly; static inline void printk_delay(void) @@ -1688,17 +1666,13 @@ asmlinkage int vprintk_emit(int facility, int level, const char *dict, size_t dictlen, const char *fmt, va_list args) { - static bool recursion_bug; static char textbuf[LOG_LINE_MAX]; char *text = textbuf; size_t text_len = 0; enum log_flags lflags = 0; unsigned long flags; - int this_cpu; int printed_len = 0; bool in_sched = false; - /* cpu currently holding logbuf_lock in this function */ - static unsigned int logbuf_cpu = UINT_MAX; if (level == LOGLEVEL_SCHED) { level = LOGLEVEL_DEFAULT; @@ -1709,42 +1683,8 @@ asmlinkage int vprintk_emit(int facility, int level, printk_delay(); printk_safe_enter_irqsave(flags); - this_cpu = smp_processor_id(); - - /* - * Ouch, printk recursed into itself! - */ - if (unlikely(logbuf_cpu == this_cpu)) { - /* - * If a crash is occurring during printk() on this CPU, - * then try to get the crash message out but make sure - * we can't deadlock. Otherwise just return to avoid the - * recursion and return - but flag the recursion so that - * it can be printed at the next appropriate moment: - */ - if (!oops_in_progress && !lockdep_recursing(current)) { - recursion_bug = true; - printk_safe_exit_irqrestore(flags); - return 0; - } - zap_locks(); - } - /* This stops the holder of console_sem just where we want him */ raw_spin_lock(&logbuf_lock); - logbuf_cpu = this_cpu; - - if (unlikely(recursion_bug)) { - static const char recursion_msg[] = - "BUG: recent printk recursion!"; - - recursion_bug = false; - /* emit KERN_CRIT message */ - printed_len += log_store(0, 2, LOG_PREFIX|LOG_NEWLINE, 0, - NULL, 0, recursion_msg, - strlen(recursion_msg)); - } - /* * The printf needs to come first; we need the syslog * prefix which might be passed-in as a parameter. @@ -1787,7 +1727,6 @@ asmlinkage int vprintk_emit(int facility, int level, printed_len += log_output(facility, level, lflags, dict, dictlen, text, text_len); - logbuf_cpu = UINT_MAX; raw_spin_unlock(&logbuf_lock); printk_safe_exit_irqrestore(flags);