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Date: Sat, 17 May 2025 01:09:07 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Stanislav Fomichev <stfomichev@gmail.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com,
	kuba@kernel.org, pabeni@redhat.com, horms@kernel.org,
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	almasrymina@google.com, kaiyuanz@google.com,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] net: devmem: remove min_t(iter_iov_len) in
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Message-ID: <20250517000907.GW2023217@ZenIV>
References: <20250517000431.558180-1-stfomichev@gmail.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Fri, May 16, 2025 at 05:04:31PM -0700, Stanislav Fomichev wrote:
> iter_iov_len looks broken for UBUF. When iov_iter_advance is called
> for UBUF, it increments iov_offset and also decrements the count.
> This makes the iterator only go over half of the range (unless I'm
> missing something).

What do you mean by "broken"?  iov_iter_len(from) == "how much data is
left in that iterator".  That goes for all flavours, UBUF included...

Confused...