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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 22 May 2018 09:38:13 -0700
Message-ID: <CA+55aFx+4D5bBYSKb5jKjJ8SP=osGB=PCf8vW3RZH+R5fp5jgQ@mail.gmail.com>
Subject: Re: [PATCH v2 01/26] rculist: introduce list_next_or_null_rr_rcu()
To: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>, linux-block <linux-block@vger.kernel.org>,
	linux-rdma <linux-rdma@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>,
	Christoph Hellwig <hch@infradead.org>, Sagi Grimberg <sagi@grimberg.me>,
	Bart Van Assche <bart.vanassche@sandisk.com>, Or Gerlitz <ogerlitz@mellanox.com>,
	Doug Ledford <dledford@redhat.com>, swapnil.ingle@profitbricks.com,
	danil.kipnis@profitbricks.com, Jinpu Wang <jinpu.wang@profitbricks.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, May 22, 2018 at 2:09 AM Roman Penyaev <
roman.penyaev@profitbricks.com> wrote:

> Should I resend current patch with more clear comments about how careful
> caller should be with a leaking pointer?

No. Even if we go your way, there is *one* single user, and that one is
special and needs to take a lot more care.

Just roll your own version, and make it an inline function like I've asked
now now many times, and add a shit-ton of explanations of why it's safe to
use in that *one* situation.

I don't want any crazy and unsafe stuff in the generic header file that
absolutely *nobody* should ever use.

                  Linus