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Date:   Fri, 30 Oct 2020 22:22:13 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Qian Cai <cai@redhat.com>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH -next] fs: Fix memory leaks in do_renameat2() error paths
Message-ID: <20201030222213.GR3576660@ZenIV.linux.org.uk>
References: <20201030152407.43598-1-cai@redhat.com>
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 <ad9357e9-8364-a316-392d-7504af614cac@kernel.dk>
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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)