From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsa@cumulusnetworks.com>
Subject: Re: [PATCH net] net: ipv6: regenerate host route if moved to gc list
Date: Sat, 22 Apr 2017 08:14:16 -0600
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To: Dmitry Vyukov <dvyukov@google.com>, Martin KaFai Lau <kafai@fb.com>
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On 4/22/17 3:14 AM, Dmitry Vyukov wrote:
>> One small question.  Why cmpxchg is needed instead
>> of a ip6_rt_put() and then assign?
>> Is it fixing another bug?
> cmpxchg here looks fishy.
> If there are no concurrent modifications, then it is not needed.
> If there are and cmpxchg fails, then we will put the installed rt and
> leak the new one.
> 

Yes, I need to convert that to changing the rt under a lock.

Leftover from the beginning of the investigation when I suspected
locking and recalled Li's patch. I'll send a v2.