tty: Prevent "read/write wait queue active!" log flooding
commit 494c1eac7e73f719af9d474a96ec8494c33efd6a upstream.
Only print one warning when a task is on the read_wait or write_wait
wait queue at final tty release.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@huawei.com>
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 19f2806..af9c573 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1634,6 +1634,7 @@
int idx;
char buf[64];
long timeout = 0;
+ int once = 1;
if (tty_paranoia_check(tty, inode, __func__))
return 0;
@@ -1714,8 +1715,11 @@
if (!do_sleep)
break;
- printk(KERN_WARNING "%s: %s: read/write wait queue active!\n",
+ if (once) {
+ once = 0;
+ printk(KERN_WARNING "%s: %s: read/write wait queue active!\n",
__func__, tty_name(tty, buf));
+ }
tty_unlock();
mutex_unlock(&tty_mutex);
schedule_timeout_killable(timeout);