Re: [RFC PATCH 00/13] Switchtec NTB Support

From: Jon Mason
Date: Mon Jun 19 2017 - 17:09:45 EST

On Mon, Jun 19, 2017 at 4:27 PM, Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote:
> On 19/06/17 02:07 PM, Jon Mason wrote:
>> I think this code is of quality enough to go from an RFC to a standard
>> patch, and we can nit pick it to death there ;-)
> Thanks!
>> Please rebase on ntb-next (which I believe you are already doing), and
>> resbutmit.
> I'll try to get the rebase done and all the feedback so far applied by
> the end of the week and resend a v1.
>> I'm thinking that we'll want to keep this series all in one place.
>> So, #2 sounds like the best option. But, I need Bjorns $0.02 on this.
> I was thinking #2 was the best choice as well but really it's for you
> maintainers to decide. And, yes, we'd want to get Bjorn's ack.

Bjorn is a busy guy, but I'm sure he'll get to it soon enough.

>> FYI, I ran smatch on the patches and got this. Please correct them in
>> v2 (or v1 of the non-RFC...however you want to think of it).
>> drivers/pci/switch/switchtec.c:484 switchtec_dev_read() error: double unlock 'mutex:&stdev->mrpc_mutex'
>> drivers/pci/switch/switchtec.c:506 switchtec_dev_read() error: double unlock 'mutex:&stdev->mrpc_mutex'
>> drivers/pci/switch/switchtec.c:513 switchtec_dev_read() warn: inconsistent returns 'mutex:&stdev->mrpc_mutex'.
> This looks like a false positive to me. The code looks correct. smatch
> may have been confused by the fact that the lock is taken by two calls
> to the static function 'lock_mutex_and_test_alive'.
> This is also part of the switchtec management driver that's already in
> the kernel and not part of the NTB related patches I sent.

Ah, no problem. I'm not a master user of smatch, but I do find it
very useful. So, I do not know of a way to run it against only the
patches being applied, and I'm not sure that is possible to do so.
Either way, I'm sure someone will address that then, given that it is
already in the kernel.

BTW, I don't think I said so, but I'm really excited to have another
piece of NTB HW supported in the kernel.


> Logan