1 files changed, 13 insertions, 36 deletions

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index de08fc90baaf..577f2288d19f 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -253,17 +253,6 @@ static int preferred_console = -1;
 int console_set_on_cmdline;
 EXPORT_SYMBOL(console_set_on_cmdline);
 
-#ifdef CONFIG_OF
-static bool of_specified_console;
-
-void console_set_by_of(void)
-{
-	of_specified_console = true;
-}
-#else
-# define of_specified_console false
-#endif
-
 /* Flag: console code may call schedule() */
 static int console_may_schedule;
 
@@ -794,8 +783,6 @@ static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from)
 	return ret;
 }
 
-static void cont_flush(void);
-
 static ssize_t devkmsg_read(struct file *file, char __user *buf,
 			    size_t count, loff_t *ppos)
 {
@@ -811,7 +798,6 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
 	if (ret)
 		return ret;
 	raw_spin_lock_irq(&logbuf_lock);
-	cont_flush();
 	while (user->seq == log_next_seq) {
 		if (file->f_flags & O_NONBLOCK) {
 			ret = -EAGAIN;
@@ -874,7 +860,6 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
 		return -ESPIPE;
 
 	raw_spin_lock_irq(&logbuf_lock);
-	cont_flush();
 	switch (whence) {
 	case SEEK_SET:
 		/* the first record */
@@ -913,7 +898,6 @@ static unsigned int devkmsg_poll(struct file *file, poll_table *wait)
 	poll_wait(file, &log_wait, wait);
 
 	raw_spin_lock_irq(&logbuf_lock);
-	cont_flush();
 	if (user->seq < log_next_seq) {
 		/* return error when data has vanished underneath us */
 		if (user->seq < log_first_seq)
@@ -1300,7 +1284,6 @@ static int syslog_print(char __user *buf, int size)
 		size_t skip;
 
 		raw_spin_lock_irq(&logbuf_lock);
-		cont_flush();
 		if (syslog_seq < log_first_seq) {
 			/* messages are gone, move to first one */
 			syslog_seq = log_first_seq;
@@ -1360,7 +1343,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 		return -ENOMEM;
 
 	raw_spin_lock_irq(&logbuf_lock);
-	cont_flush();
 	if (buf) {
 		u64 next_seq;
 		u64 seq;
@@ -1522,7 +1504,6 @@ int do_syslog(int type, char __user *buf, int len, int source)
 	/* Number of chars in the log buffer */
 	case SYSLOG_ACTION_SIZE_UNREAD:
 		raw_spin_lock_irq(&logbuf_lock);
-		cont_flush();
 		if (syslog_seq < log_first_seq) {
 			/* messages are gone, move to first one */
 			syslog_seq = log_first_seq;
@@ -2185,27 +2166,20 @@ void resume_console(void)
 
 /**
  * console_cpu_notify - print deferred console messages after CPU hotplug
- * @self: notifier struct
- * @action: CPU hotplug event
- * @hcpu: unused
+ * @cpu: unused
  *
  * If printk() is called from a CPU that is not online yet, the messages
  * will be spooled but will not show up on the console.  This function is
  * called when a new CPU comes online (or fails to come up), and ensures
  * that any such output gets printed.
  */
-static int console_cpu_notify(struct notifier_block *self,
-	unsigned long action, void *hcpu)
-{
-	switch (action) {
-	case CPU_ONLINE:
-	case CPU_DEAD:
-	case CPU_DOWN_FAILED:
-	case CPU_UP_CANCELED:
+static int console_cpu_notify(unsigned int cpu)
+{
+	if (!cpuhp_tasks_frozen) {
 		console_lock();
 		console_unlock();
 	}
-	return NOTIFY_OK;
+	return 0;
 }
 
 /**
@@ -2657,7 +2631,7 @@ void register_console(struct console *newcon)
 	 *	didn't select a console we take the first one
 	 *	that registers here.
 	 */
-	if (preferred_console < 0 && !of_specified_console) {
+	if (preferred_console < 0) {
 		if (newcon->index < 0)
 			newcon->index = 0;
 		if (newcon->setup == NULL ||
@@ -2843,6 +2817,7 @@ EXPORT_SYMBOL(unregister_console);
 static int __init printk_late_init(void)
 {
 	struct console *con;
+	int ret;
 
 	for_each_console(con) {
 		if (!keep_bootcon && con->flags & CON_BOOT) {
@@ -2857,7 +2832,12 @@ static int __init printk_late_init(void)
 				unregister_console(con);
 		}
 	}
-	hotcpu_notifier(console_cpu_notify, 0);
+	ret = cpuhp_setup_state_nocalls(CPUHP_PRINTK_DEAD, "printk:dead", NULL,
+					console_cpu_notify);
+	WARN_ON(ret < 0);
+	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "printk:online",
+					console_cpu_notify, NULL);
+	WARN_ON(ret < 0);
 	return 0;
 }
 late_initcall(printk_late_init);
@@ -3039,7 +3019,6 @@ void kmsg_dump(enum kmsg_dump_reason reason)
 		dumper->active = true;
 
 		raw_spin_lock_irqsave(&logbuf_lock, flags);
-		cont_flush();
 		dumper->cur_seq = clear_seq;
 		dumper->cur_idx = clear_idx;
 		dumper->next_seq = log_next_seq;
@@ -3130,7 +3109,6 @@ bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
 	bool ret;
 
 	raw_spin_lock_irqsave(&logbuf_lock, flags);
-	cont_flush();
 	ret = kmsg_dump_get_line_nolock(dumper, syslog, line, size, len);
 	raw_spin_unlock_irqrestore(&logbuf_lock, flags);
 
@@ -3173,7 +3151,6 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
 		goto out;
 
 	raw_spin_lock_irqsave(&logbuf_lock, flags);
-	cont_flush();
 	if (dumper->cur_seq < log_first_seq) {
 		/* messages are gone, move to first available one */
 		dumper->cur_seq = log_first_seq;