From mboxrd@z Thu Jan  1 00:00:00 1970
From: William Hua <william.hua@canonical.com>
Subject: Re: [PATCH] rhashtable: Always allocate at least one bucket lock
Date: Wed, 16 Dec 2015 02:33:30 -0500
Message-ID: <567113CA.8030108@canonical.com>
References: <20151216055310.GA23634@gondor.apana.org.au>
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To: Herbert Xu <herbert@gondor.apana.org.au>
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On 12/16/2015 12:53 AM, Herbert Xu wrote:
> William Hua <william.hua@canonical.com> wrote:
>> No bucket locks are allocated when an rhashtable is initialized with
>> fewer than two elements. In this special case, we should allocate at
>> least one to prevent a segfault.
>>
>> Signed-off-by: William Hua <william.hua@canonical.com>
> 
> Huh? The minimum hash table size is 4.  How are you getting an
> rhashtable that's smaller than the required minimum?

I wasn't aware there was an enforced minimum size. I simply set the 
nelem_hint in the rhastable_params struct to 1, expecting it to grow as
needed. This caused a segfault afterwards when trying to insert an
element.