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Date: Thu, 23 Jul 2026 11:42:39 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Laurent Vivier <lvivier@redhat.com>
Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
 linux-usb@vger.kernel.org, Stefano Brivio <sbrivio@redhat.com>, Oliver
 Neukum <oneukum@suse.com>, stable@vger.kernel.org
Subject: Re: [PATCH net] usbnet: cap max_mtu for drivers without bind
 callback
Message-ID: <20260723114239.709d2477@kernel.org>
In-Reply-To: <ce31de54-d46c-4738-909c-91ef229b7d9e@redhat.com>
References: <20260717151626.2913171-1-lvivier@redhat.com>
	<20260723084319.40fee97f@kernel.org>
	<ce31de54-d46c-4738-909c-91ef229b7d9e@redhat.com>
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On Thu, 23 Jul 2026 19:20:30 +0200 Laurent Vivier wrote:
>   	dev->hard_mtu = net->mtu + net->hard_header_len;
>   	net->min_mtu = 0;
> -	net->max_mtu = ETH_MAX_MTU;
> +	net->max_mtu = dev->hard_mtu - net->hard_header_len;

But we assigned 

	dev->hard_mtu = net->mtu + net->hard_header_len;

two lines earlier, so this is just:

	net->max_mtu = net->mtu;

is this the expected max_mtu for most USB adapters?
I suppose so given the patch under discussion?