Re: [PATCH net v4] net: lapb: Add locking to the lapb module

From: Xie He
Date: Wed Jan 20 2021 - 07:09:42 EST


On Wed, Jan 20, 2021 at 2:58 AM Martin Schiller <ms@xxxxxxxxxx> wrote:
>
> Can you please add a Changelog. What was changed in v4?

Sorry, I forgot this. Here is the change log:

--- Changes from v3 to v4 ---

Only lapb_unregister has been changed.

v3 has a problem. When "del_timer_sync(&lapb->t1timer)" is called, if
the t1timer is running, it may restart itself by calling
lapb_start_t1timer. This way, del_timer_sync would not be able to
guarantee the t1timer has been completely stopped.

v4 fixed this problem by first calling lapb_stop_t1timer, making use
of its (new) ability of aborting running timers, and then calling
del_timer_sync to guarantee the t1timer has been stopped.

--- Changes from v2 to v3 ---

Created a new __lapb_disconnect_request function and made it be called
from both lapb_disconnect_request and lapb_device_event. This reduced
redundant code.

--- Changes from v1 to v2 ---

Broke long lines to keep the line lengths within 80 characters.