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Date:   Mon, 19 Dec 2022 14:10:00 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Jacob Keller <jacob.e.keller@intel.com>
Cc:     <jiri@resnulli.us>, <leon@kernel.org>, <netdev@vger.kernel.org>
Subject: Re: [RFC net-next 00/10] devlink: remove the wait-for-references on
 unregister
Message-ID: <20221219141000.32c94617@kernel.org>
In-Reply-To: <3d169051-e095-6a2a-d5d8-409a5ad8af4b@intel.com>
References: <20221217011953.152487-1-kuba@kernel.org>
        <3d169051-e095-6a2a-d5d8-409a5ad8af4b@intel.com>
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On Mon, 19 Dec 2022 09:38:09 -0800 Jacob Keller wrote:
> On 12/16/2022 5:19 PM, Jakub Kicinski wrote:
> > This set is on top of the previous RFC.
> > 
> > Move the registration and unregistration of the devlink instances
> > under their instance locks. Don't perform the netdev-style wait
> > for all references when unregistering the instance.
> 
> Could you explain the reasoning/benefits here? I'm sure some of this is
> explained in each commit message as well but it would help to understand
> the overall series.

Fair point, I'll add this:

  Yang Yingliang reported [1] a use-after-free in devlink because netdev
  paths are able to acquire a reference on the devlink instances before
  they are registered.

[1]
https://lore.kernel.org/all/20221122121048.776643-1-yangyingliang@huawei.com/