tty: release BTM while sleeping in block_til_ready
Most tty drivers may block while opening a device.
Since this possibly depends on another thread
closing it first and both threads may need the BTM,
we need to release it here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/serial/68328serial.c b/drivers/serial/68328serial.c
index 9330edb..d8204f4 100644
--- a/drivers/serial/68328serial.c
+++ b/drivers/serial/68328serial.c
@@ -1235,7 +1235,9 @@
retval = -ERESTARTSYS;
break;
}
+ tty_unlock();
schedule();
+ tty_lock();
}
current->state = TASK_RUNNING;
remove_wait_queue(&info->open_wait, &wait);
diff --git a/drivers/serial/68360serial.c b/drivers/serial/68360serial.c
index edcf1cc..0dff3bb 100644
--- a/drivers/serial/68360serial.c
+++ b/drivers/serial/68360serial.c
@@ -1860,7 +1860,9 @@
printk("block_til_ready blocking: ttys%d, count = %d\n",
info->line, state->count);
#endif
+ tty_unlock();
schedule();
+ tty_lock();
}
current->state = TASK_RUNNING;
remove_wait_queue(&info->open_wait, &wait);
diff --git a/drivers/serial/crisv10.c b/drivers/serial/crisv10.c
index 8e356c5..5696710 100644
--- a/drivers/serial/crisv10.c
+++ b/drivers/serial/crisv10.c
@@ -4066,7 +4066,9 @@
printk("block_til_ready blocking: ttyS%d, count = %d\n",
info->line, info->count);
#endif
+ tty_unlock();
schedule();
+ tty_lock();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&info->open_wait, &wait);