Re: [PATCH] usb: host: fhci-hcd: annotate PIPE_CONTROL switch case with fallthrough

From: Gustavo A. R. Silva
Date: Mon Feb 17 2020 - 11:14:13 EST


Sorry for the late reply. I wasn't aware of this thread until now.

Please, see my comments below...

On 2/17/20 08:18, Greg Kroah-Hartman wrote:
> On Mon, Feb 17, 2020 at 03:12:21PM +0100, Rasmus Villemoes wrote:
>> On 17/02/2020 10.38, Greg Kroah-Hartman wrote:
>>> On Thu, Feb 13, 2020 at 02:35:18PM +0100, Rasmus Villemoes wrote:
>>>> On 13/02/2020 13.56, Greg Kroah-Hartman wrote:
>>>>> Shouldn't this be /* fall through */ instead?
>>>>> Gustavo, what's the best practice here, I count only a few
>>>>> "fallthrough;" instances in the kernel, although one is in our coding
>>>>> style document, and thousands of the /* */ version.
>>>> Yes, I went with the attribute/macro due to that, and the history is
>>>> that Linus applied Joe's patches directly
>>>> (,
>>>> so I assumed that meant the Penguin decided that the attribute/macro is
>>>> the right thing to do for new code, while existing comment annotations
>>>> can be left alone or changed piecemeal as code gets refactored anyway.
>>> But, to be fair, Gustavo went and fixed up thousands of these, with the
>>> /* */ version, not the attribute.
>>> Gustavo, can coverity notice the "fallthrough;" attribute properly? I
>>> don't want to start adding things that end up triggering
>>> false-positives.
>> I'm not Gustavo, and I don't know the answer, but 1.5 years ago some guy
>> named greg k-h suggested that coverity does grok the fallthrough attribute:
> I wouldn't trust anything that bum says :)
> Ok, I don't remember saying that at all, but I'll wait a day or two to
> get Gustavo's opinion befor applying the patch.

We are good to go with the 'fallthrough' pseudo keyword. Linus is OK with

The comment annotations will eventually be transformed to "fallthrough;"