netdev - Re: [PATCH net-next 2/3] ezchip: Switch to some devm

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:   Thu, 5 Jan 2023 10:01:52 +0200
From:   Leon Romanovsky <leon@...nel.org>
To:     Christophe JAILLET <christophe.jaillet@...adoo.fr>
Cc:     Jakub Kicinski <kuba@...nel.org>,
        "David S . Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Paolo Abeni <pabeni@...hat.com>, linux-kernel@...r.kernel.org,
        kernel-janitors@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [PATCH net-next 2/3] ezchip: Switch to some devm_ function to
 simplify code

On Thu, Jan 05, 2023 at 07:27:00AM +0100, Christophe JAILLET wrote:
> Le 05/01/2023 à 05:54, Jakub Kicinski a écrit :
> > On Wed,  4 Jan 2023 22:05:33 +0100 Christophe JAILLET wrote:
> > > devm_alloc_etherdev() and devm_register_netdev() can be used to simplify
> > > code.
> > > 
> > > Now the error handling path of the probe and the remove function are
> > > useless and can be removed completely.
> > 
> > Right, but this is very likely a dead driver. Why invest in refactoring?
> > 
> 
> Hi Jakub,
> 
> this driver was just randomly picked as an example.
> 
> My main point is in the cover letter. I look for feed-back to know if
> patches like that are welcomed. Only the first, Only the second, Both or
> None.
> 
> 
> I put it here, slightly rephrased:
> 
> 
> These patches (at least 1 and 2) can be seen as an RFC for net MAINTAINERS,
> to see if there is any interest in:
>   - axing useless netif_napi_del() calls, when free_netdev() is called just
> after. (patch 1)
>   - simplifying code with axing the error handling path of the probe and the
> remove function in favor of using devm_ functions (patch 2)

I would say no. In many occasions, the devm_* calls were marked as harmful.
Latest talk about devm_kzalloc(): https://lpc.events/event/16/contributions/1227/

Thanks

> 
>   or
> 
> if it doesn't worth it and would only waste MAINTAINERS' time to review what
> is in fact only code clean-ups.
> 
> 
> The rational for patch 1 is based on Jakub's comment [1].
> free_netdev() already cleans up NAPIs (see [2]).
> 
> CJ
> 
> [1]: https://lore.kernel.org/all/20221221174043.1191996a@kernel.org/
> [2]: https://elixir.bootlin.com/linux/v6.2-rc1/source/net/core/dev.c#L10710