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Date: Mon, 30 Oct 2023 14:25:42 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: longli@linuxonhyperv.com
Cc: "K. Y. Srinivasan" <kys@microsoft.com>, Haiyang Zhang
 <haiyangz@microsoft.com>, Wei Liu <wei.liu@kernel.org>, Dexuan Cui
 <decui@microsoft.com>, "David S. Miller" <davem@davemloft.net>, Eric
 Dumazet <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>,
 linux-hyperv@vger.kernel.org, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, Long Li <longli@microsoft.com>
Subject: Re: [Patch v2] hv_netvsc: Mark VF as slave before exposing it to
 user-mode
Message-ID: <20231030142542.6640190b@kernel.org>
In-Reply-To: <1698440390-13719-1-git-send-email-longli@linuxonhyperv.com>
References: <1698440390-13719-1-git-send-email-longli@linuxonhyperv.com>
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On Fri, 27 Oct 2023 13:59:50 -0700 longli@linuxonhyperv.com wrote:
> When a VF is being exposed form the kernel, it should be marked as "slave"
> before exposing to the user-mode. The VF is not usable without netvsc running
> as master. The user-mode should never see a VF without the "slave" flag.
> 
> This commit moves the code of setting the slave flag to the time before VF is
> exposed to user-mode.

Can you give a real example in the commit message of a flow in user
space which would get confused by seeing the VF netdev without
IFF_SLAVE?

You're only moving setting IFF_SLAVE but not linking the master,
is there no code which would assume that if SLAVE is set there 
is a master?