From: Dongxiao Xu <dongxiao.xu at intel.com>
When the two locks are nested, the code should always first acquire file_lock,
and then acquire device_lock in order not to generate dead-lock race.
Signed-off-by: Dongxiao Xu <dongxiao.xu at intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at suse.de>
---
drivers/staging/heci/io_heci.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/heci/io_heci.c b/drivers/staging/heci/io_heci.c
index 619eeed..53dc770 100644
--- a/drivers/staging/heci/io_heci.c
+++ b/drivers/staging/heci/io_heci.c
@@ -277,14 +277,16 @@ int heci_ioctl_connect_client(struct iamt_heci_device *dev, int if_num,
}
goto end;
}
+ spin_unlock_bh(&dev->device_lock);
+
spin_lock(&file_ext->file_lock);
+ spin_lock_bh(&dev->device_lock);
if (file_ext->state != HECI_FILE_CONNECTING) {
rets = -ENODEV;
- spin_unlock(&file_ext->file_lock);
spin_unlock_bh(&dev->device_lock);
+ spin_unlock(&file_ext->file_lock);
goto end;
}
- spin_unlock(&file_ext->file_lock);
/* prepare the output buffer */
client = (struct heci_client *) res_msg.data;
client->max_msg_length = dev->me_clients[i].props.max_msg_length;
@@ -312,6 +314,7 @@ int heci_ioctl_connect_client(struct iamt_heci_device *dev, int if_num,
&dev->ctrl_wr_list.heci_cb.cb_list);
}
spin_unlock_bh(&dev->device_lock);
+ spin_unlock(&file_ext->file_lock);
err = wait_event_timeout(dev->wait_recvd_msg,
(HECI_FILE_CONNECTED == file_ext->state
|| HECI_FILE_DISCONNECTED == file_ext->state),
--
1.6.3.2
