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Date:   Thu, 6 Jul 2023 07:37:35 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Christian Brauner <brauner@kernel.org>
Cc:     Hou Tao <houtao@huaweicloud.com>,
        Alexey Gladkov <legion@kernel.org>, bpf@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>
Subject: Re: [PATCH v1] fs: Add kfuncs to handle idmapped mounts
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On Tue, Jul 04, 2023 at 03:01:21PM +0200, Christian Brauner wrote:
> That's too much stability for my taste for these helpers. The helpers
> here exposed have been modified multiple times and once we wean off
> idmapped mounts from user namespaces completely they will change again.
> So I'm fine if they're traceable but not as kfuncs with any - even
> minimal - stability guarantees.

I fully agree.  I also don't think any eBPF program has any business
looking at idmapping.