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Date:   Mon, 12 Oct 2020 09:50:42 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Ondrej Zary <linux@zary.sk>
Cc:     Oliver Neukum <oneukum@suse.com>, netdev@vger.kernel.org,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] cx82310_eth: re-enable ethernet mode after router
 reboot
Message-ID: <20201012095042.4f5b4843@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <202010121242.55826.linux@zary.sk>
References: <20201010140048.12067-1-linux@zary.sk>
        <20201011155539.315bf5aa@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
        <202010121242.55826.linux@zary.sk>
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On Mon, 12 Oct 2020 12:42:55 +0200 Ondrej Zary wrote:
> On Monday 12 October 2020, Jakub Kicinski wrote:
> > On Sat, 10 Oct 2020 16:00:46 +0200 Ondrej Zary wrote:  
> > > When the router is rebooted without a power cycle, the USB device
> > > remains connected but its configuration is reset. This results in
> > > a non-working ethernet connection with messages like this in syslog:
> > > 	usb 2-2: RX packet too long: 65535 B
> > >
> > > Re-enable ethernet mode when receiving a packet with invalid size of
> > > 0xffff.  
> >
> > Patch looks good, but could you explain what's a reboot without a power
> > cycle in this case? The modem gets reset but USB subsystem doesn't know
> > it and doesn't go though a unbind() + bind() cycle?  
> 
> The router can be rebooted through the web interface. The reboot does not 
> disconnect the USB device - it remains connected as if nothing happened. Only 
> wrong data starts to come in.

I see. Applied to net-next, thanks!