From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jens Axboe <axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org>
Subject: Re: IORING_REGISTER_CREDS[_UPDATE]() and credfd_create()?
Date: Tue, 28 Jan 2020 17:20:00 -0700
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To: Pavel Begunkov <asml.silence-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Stefan Metzmacher <metze-eUNUBHrolfbYtjvyW6yDsg@public.gmane.org>
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On 1/28/20 5:10 PM, Pavel Begunkov wrote:
>>>> Checked out ("don't use static creds/mm assignments")
>>>>
>>>> 1. do we miscount cred refs? We grab one in get_current_cred() for each async
>>>> request, but if (worker->creds != work->creds) it will never be put.
>>>
>>> Yeah I think you're right, that needs a bit of fixing up.
>>
> 
> Hmm, it seems it leaks it unconditionally, as it grabs in a ref in
> override_creds().
> 

We grab one there, and an extra one. Then we drop one of them inline,
and the other in __io_req_aux_free().

-- 
Jens Axboe