From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran@gmail.com>
Subject: Re: [PATCH] usbnet: drop unneeded check for NULL
Date: Thu, 6 Sep 2012 09:52:55 +0200
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Cc: David Miller <davem@davemloft.net>, oneukum@suse.de,
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	Alexander Duyck <alexander.h.duyck@intel.com>
To: Ben Hutchings <bhutchings@solarflare.com>
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On Wed, Sep 05, 2012 at 11:14:35PM +0100, Ben Hutchings wrote:
> 
> Perhaps the skb_tx_timestamp() call should be moved below the
> 'if (info->tx_fixup)' block, at which point skb is definitely non-null.

No, that block shuffles the packet alignment all around, and spoils
any code which needs to match packets with time stamps.

> It doesn't look like cdc-ncm will provide useful timestamps either way.

But it is not the only user of this code. Furthermore, the PHY driver
will want a chance to provide a HW time stamp in any case.

Thanks,
Richard