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Date:   Thu, 1 Jun 2023 21:20:43 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     David Howells <dhowells@redhat.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
        David Ahern <dsahern@kernel.org>,
        Matthew Wilcox <willy@infradead.org>,
        Jens Axboe <axboe@kernel.dk>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Chuck Lever <chuck.lever@oracle.com>,
        Boris Pismenny <borisp@nvidia.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Christoph Hellwig <hch@infradead.org>
Subject: Re: Bug in short splice to socket?
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On Thu, 01 Jun 2023 18:14:40 +0100 David Howells wrote:
> The answer then might be to make TLS handle a zero-length send()

IDK. Eric added MSG_SENDPAGE_NOTLAST 11 years ago, to work around 
this exact problem. Your refactoring happens to break it and what
you're saying sounds to me more or less like "MSG_SENDPAGE_NOTLAST 
is unnecessary, it's user's fault".

A bit unconvincing. Maybe Eric would chime in, I'm not too familiar
with the deadly mess of the unchecked sendmsg()/sendpage() flags.