Re: Can a driver->probe be called for two devices at the same time (WAS: Re: [PATCH] crypto/ccp: don't disable interrupts while setting up debugfs)

Gary R Hook
2018-02-27T17:45:59Z

On 02/27/2018 11:33 AM, Sebastian Andrzej Siewior wrote:
> On 2018-02-27 11:08:56 [-0600], Gary R Hook wrote:
>> That issue remains unclear to me: Are probes of PCI devices guaranteed to be
>> serialized? Observations on my CCPs says that they occur in order, but I
>> don't know for certain that serialization is guaranteed.
>>
>> Is there a definitive statement on this somewhere that I just don't know
>> about?
>
> So the question if a driver can probe two devices simultaneously. I'm
> not sure. We have PROBE_PREFER_ASYNCHRONOUS which defers the probe to
> worker. However I have no idea if two of those worker can run at the
> same time.
>
>> I think a mutex would be just fine; I got this wrong, clearly. Let me work
>> up a patch using a mutex.
>
> I've sent one. Why not just ack it and be done with it?
>
>> Gary
>
> Sebastian
>

Sorry, too much chaos right now. Of course.