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Subject: Re: [PATCH -next] fs: Fix memory leaks in do_renameat2() error paths
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Qian Cai <cai@redhat.com>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20201030152407.43598-1-cai@redhat.com>
 <20201030184255.GP3576660@ZenIV.linux.org.uk>
 <ad9357e9-8364-a316-392d-7504af614cac@kernel.dk>
 <20201030184918.GQ3576660@ZenIV.linux.org.uk>
 <d858ba48-624f-43be-93cf-07d94f0ebefd@kernel.dk>
 <20201030222213.GR3576660@ZenIV.linux.org.uk>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <a1e17902-a204-f03d-2a51-469633eca751@kernel.dk>
Date:   Fri, 30 Oct 2020 17:21:39 -0600
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On 10/30/20 4:22 PM, Al Viro wrote:
> On Fri, Oct 30, 2020 at 02:33:11PM -0600, Jens Axboe wrote:
>> On 10/30/20 12:49 PM, Al Viro wrote:
>>> On Fri, Oct 30, 2020 at 12:46:26PM -0600, Jens Axboe wrote:
>>>
>>>> See other reply, it's being posted soon, just haven't gotten there yet
>>>> and it wasn't ready.
>>>>
>>>> It's a prep patch so we can call do_renameat2 and pass in a filename
>>>> instead. The intent is not to have any functional changes in that prep
>>>> patch. But once we can pass in filenames instead of user pointers, it's
>>>> usable from io_uring.
>>>
>>> You do realize that pathname resolution is *NOT* offloadable to helper
>>> threads, I hope...
>>
>> How so? If we have all the necessary context assigned, what's preventing
>> it from working?
> 
> Semantics of /proc/self/..., for starters (and things like /proc/mounts, etc.
> *do* pass through that, /dev/stdin included)

Don't we just need ->thread_pid for that to work?

-- 
Jens Axboe