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Subject: Re: kernel BUG at net/core/skbuff.c:LINE! (2)
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Xin Long <lucien.xin@gmail.com>
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On Sun, 2017-12-10 at 12:36 +0800, Xin Long wrote:
> The new patch works to me, just two questions:
> 1. should it use "idev->cnf.mtu6" here for mld ?

No idea why some parts of IPv6 would use a different view of device
mtu. Maybe others can comment.

> 
> 2.  'if (int < unsigned int)' is still not nice, though in 'if
> (AVAILABLE(skb) < sizeof())'
>      AVAILABLE(skb) seems always to return >= 0 after your patch.

Really if AVAILABLE(skb) was negative, a bug already happened.