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Date: Mon, 3 Aug 2026 12:54:14 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Mina Almasry <almasrymina@google.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
 davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
 horms@kernel.org, kerneljasonxing@gmail.com, kuniyu@google.com,
 bjorn@kernel.org, jiayuan.chen@linux.dev, kaiyuanz@google.com,
 willemb@google.com, asml.silence@gmail.com, sdf@fomichev.me,
 bobbyeshleman@gmail.com, fw@strlen.de, Neal Cardwell
 <ncardwell@google.com>, Ralf Lici <ralf@mandelbit.com>, Will Deacon
 <will@kernel.org>
Subject: Re: [PATCH net v2 2/3] net: devmem: return EMSGSIZE on type
 mismatch
Message-ID: <20260803125414.500138af@kernel.org>
In-Reply-To: <20260803171441.408014-2-almasrymina@google.com>
References: <20260803171441.408014-1-almasrymina@google.com>
	<20260803171441.408014-2-almasrymina@google.com>
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On Mon,  3 Aug 2026 17:14:40 +0000 Mina Almasry wrote:
> When a devmem payload mixes with a standard page payload, return
> -EMSGSIZE instead of -EFAULT. This enables tcp_sendmsg to seamlessly
> fall back to creating a new segment instead of failing the socket send.

Sure but AFAIU this was discovered during a ML discussion,
so the change is an improvement for net-next rather than a fix.
Do you have any reason to believe that real applications hit
the error?

Also please add cover letters for submissions with more than 2 patches.