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Date: Mon, 9 Jun 2025 12:32:55 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Byungchul Park <byungchul@sk.com>
Cc: willy@infradead.org, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel_team@skhynix.com,
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 horms@kernel.org, linux-rdma@vger.kernel.org, bpf@vger.kernel.org,
 vishal.moola@gmail.com
Subject: Re: [PATCH net-next 1/9] netmem: introduce struct netmem_desc
 mirroring struct page
Message-ID: <20250609123255.18f14000@kernel.org>
In-Reply-To: <20250609043225.77229-2-byungchul@sk.com>
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On Mon,  9 Jun 2025 13:32:17 +0900 Byungchul Park wrote:
> To simplify struct page, the page pool members of struct page should be
> moved to other, allowing these members to be removed from struct page.
> 
> Introduce a network memory descriptor to store the members, struct
> netmem_desc, and make it union'ed with the existing fields in struct
> net_iov, allowing to organize the fields of struct net_iov.

What's the intended relation between the types?

netmem_ref exists to clearly indicate that memory may not be readable.
Majority of memory we expect to allocate from page pool must be
kernel-readable. What's the plan for reading the "single pointer"
memory within the kernel?

I think you're approaching this problem from the easiest and least
relevant direction. Are you coordinating with David Howells?