Re: Disconnect race in Gadget core

[Felipe Balbi <balbi@kernel.org>]

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Hi,

Alan Stern <stern@rowland.harvard.edu> writes:
> On Sun, May 16, 2021 at 12:43:58PM +0300, Felipe Balbi wrote:
>> 
>> Hi,
>> 
>> Alan Stern <stern@rowland.harvard.edu> writes:
>> >
>> > If it's okay to call those functions in interrupt context then the 
>> > kerneldoc definitely should be updated.  However, I don't see why you 
>> > would want to make DELAYED_STATUS mandatory.  If all the necessary work 
>> > can be done in the set_alt handler, why not return the status 
>> > immediately?
>> 
>> because we avoid a special case. Instead of having magic return value to
>> mean "Don't do anything until I enqueue a request" we can just make that
>> an assumption, i.e. gadget driver *must* enqueue requests for data and
>> status stages.
>
> Okay.  But that would require auditing every gadget/function driver to 
> ensure that they _do_ enqueue status stage requests, and auditing every 
> UDC driver to ensure they don't send unsolicited status responses to 
> control requests with data stages.  Until this happens, we're forced to 
> use the DELAYED_STATUS magic value.

sure, that's work for the future :-)

-- 
balbi

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