linux-kernel - Re: [RFC PATCH net-next v1 4/4] net: page_pool: use netmem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Fri, 15 Dec 2023 19:04:49 +0800
From: Yunsheng Lin <linyunsheng@...wei.com>
To: Shakeel Butt <shakeelb@...gle.com>, Mina Almasry <almasrymina@...gle.com>
CC: <linux-kernel@...r.kernel.org>, <netdev@...r.kernel.org>,
	<bpf@...r.kernel.org>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar
	<mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, Dave Hansen
	<dave.hansen@...ux.intel.com>, <x86@...nel.org>, "H. Peter Anvin"
	<hpa@...or.com>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>, "Rafael J.
 Wysocki" <rafael@...nel.org>, Sumit Semwal <sumit.semwal@...aro.org>,
	Christian König <christian.koenig@....com>, Michael Chan
	<michael.chan@...adcom.com>, "David S. Miller" <davem@...emloft.net>, Eric
 Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, Paolo Abeni
	<pabeni@...hat.com>, Alexei Starovoitov <ast@...nel.org>, Daniel Borkmann
	<daniel@...earbox.net>, Jesper Dangaard Brouer <hawk@...nel.org>, John
 Fastabend <john.fastabend@...il.com>, Wei Fang <wei.fang@....com>, Shenwei
 Wang <shenwei.wang@....com>, Clark Wang <xiaoning.wang@....com>, NXP Linux
 Team <linux-imx@....com>, Jeroen de Borst <jeroendb@...gle.com>, Praveen
 Kaligineedi <pkaligineedi@...gle.com>, Shailend Chand <shailend@...gle.com>,
	Yisen Zhuang <yisen.zhuang@...wei.com>, Salil Mehta <salil.mehta@...wei.com>,
	Jesse Brandeburg <jesse.brandeburg@...el.com>, Tony Nguyen
	<anthony.l.nguyen@...el.com>, Thomas Petazzoni
	<thomas.petazzoni@...tlin.com>, Marcin Wojtas <mw@...ihalf.com>, Russell King
	<linux@...linux.org.uk>, Sunil Goutham <sgoutham@...vell.com>, Geetha
 sowjanya <gakula@...vell.com>, Subbaraya Sundeep <sbhatta@...vell.com>,
	hariprasad <hkelam@...vell.com>, Felix Fietkau <nbd@....name>, John Crispin
	<john@...ozen.org>, Sean Wang <sean.wang@...iatek.com>, Mark Lee
	<Mark-MC.Lee@...iatek.com>, Lorenzo Bianconi <lorenzo@...nel.org>, Matthias
 Brugger <matthias.bgg@...il.com>, AngeloGioacchino Del Regno
	<angelogioacchino.delregno@...labora.com>, Saeed Mahameed
	<saeedm@...dia.com>, Leon Romanovsky <leon@...nel.org>, Horatiu Vultur
	<horatiu.vultur@...rochip.com>, <UNGLinuxDriver@...rochip.com>, "K. Y.
 Srinivasan" <kys@...rosoft.com>, Haiyang Zhang <haiyangz@...rosoft.com>, Wei
 Liu <wei.liu@...nel.org>, Dexuan Cui <decui@...rosoft.com>, Jassi Brar
	<jaswinder.singh@...aro.org>, Ilias Apalodimas <ilias.apalodimas@...aro.org>,
	Alexandre Torgue <alexandre.torgue@...s.st.com>, Jose Abreu
	<joabreu@...opsys.com>, Maxime Coquelin <mcoquelin.stm32@...il.com>,
	Siddharth Vadapalli <s-vadapalli@...com>, Ravi Gunasekaran
	<r-gunasekaran@...com>, Roger Quadros <rogerq@...nel.org>, Jiawen Wu
	<jiawenwu@...stnetic.com>, Mengyuan Lou <mengyuanlou@...-swift.com>, Ronak
 Doshi <doshir@...are.com>, VMware PV-Drivers Reviewers
	<pv-drivers@...are.com>, Ryder Lee <ryder.lee@...iatek.com>, Shayne Chen
	<shayne.chen@...iatek.com>, Kalle Valo <kvalo@...nel.org>, Juergen Gross
	<jgross@...e.com>, Stefano Stabellini <sstabellini@...nel.org>, Oleksandr
 Tyshchenko <oleksandr_tyshchenko@...m.com>, Andrii Nakryiko
	<andrii@...nel.org>, Martin KaFai Lau <martin.lau@...ux.dev>, Song Liu
	<song@...nel.org>, Yonghong Song <yonghong.song@...ux.dev>, KP Singh
	<kpsingh@...nel.org>, Stanislav Fomichev <sdf@...gle.com>, Hao Luo
	<haoluo@...gle.com>, Jiri Olsa <jolsa@...nel.org>, Stefan Hajnoczi
	<stefanha@...hat.com>, Stefano Garzarella <sgarzare@...hat.com>, Shuah Khan
	<shuah@...nel.org>, Mickaël Salaün <mic@...ikod.net>,
	Nathan Chancellor <nathan@...nel.org>, Nick Desaulniers
	<ndesaulniers@...gle.com>, Bill Wendling <morbo@...gle.com>, Justin Stitt
	<justinstitt@...gle.com>, Jason Gunthorpe <jgg@...dia.com>, Willem de Bruijn
	<willemdebruijn.kernel@...il.com>
Subject: Re: [RFC PATCH net-next v1 4/4] net: page_pool: use netmem_t instead
 of struct page in API

On 2023/12/15 10:11, Shakeel Butt wrote:
> On Thu, Dec 14, 2023 at 08:27:55AM -0800, Mina Almasry wrote:
>> On Thu, Dec 14, 2023 at 4:05 AM Yunsheng Lin <linyunsheng@...wei.com> wrote:
>>>
> [...]
>>> I perfer the second one personally, as devmem means that it is not
>>> readable from cpu.
>>
>> From my POV it has to be the first one. We want to abstract the memory
>> type from the drivers as much as possible, not introduce N new memory
>> types and ask the driver to implement new code for each of them
>> separately.

That was my initial thinking too:
https://www.spinics.net/lists/netdev/msg949376.html

But after discussion, it may make more sense to have two sets of API from the
driver's piont of view if we want a complete safe type protection, so that
compiler can check everything statically and devmem driver API have a clear
semantic:
1. devmem is not allowed to be called into mm subsystem.
2. it will not provide a API like page_address().

>>
> 
> Agree with Mina's point. Let's aim to decouple memory types from
> drivers.
> .
>