Re: [sgi-xp] Missing break or false positive?

From: Gustavo A. R. Silva
Date: Wed Mar 20 2019 - 11:44:31 EST




On 3/20/19 10:23 AM, Robin Holt wrote:
> I am sorry for my delayed response. I missed the earlier email.
>
> On Wed, Mar 20, 2019 at 9:37 AM Gustavo A. R. Silva
> <gustavo@xxxxxxxxxxxxxx> wrote:
>>
> ...
>>> I'm taking a look into the following piece of code in drivers/misc/sgi-xp/xpc_uv.c:
> ...
>>> and I'm trying to figure out if the following warning is due to a missing break
>>> at the end of the case, or if this is just a false positive and a /* fall through */
>>> annotation should be added:
>
> The fall-through is by design. The protocol previously had a windows
> of failure where a connection
> could be in the process of being established and a failure could be
> detected prior to the
> handling of the establishment message. I added the new open complete
> message and leveraged
> the fall-through to mark the connection established.
>

Great. I see now.

> Please let me know if you do not intend to submit a patch for this.
>

I will send a patch to add the fall-through comment and fix the following
warning:

drivers/misc/sgi-xp/xpc_uv.c: In function âxpc_handle_activate_mq_msg_uvâ:
drivers/misc/sgi-xp/xpc_uv.c:573:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
xpc_wakeup_channel_mgr(part);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/misc/sgi-xp/xpc_uv.c:575:2: note: here
case XPC_ACTIVATE_MQ_MSG_MARK_ENGAGED_UV:
^~~~

Notice that this is part of the ongoing efforts to enable -Wimplicit-fallthrough.

Thanks, Robin.
--
Gustavo