Re: [PATCH] lib: fix data race in rhashtable_rehash_one

From: Dmitry Vyukov
Date: Tue Sep 22 2015 - 04:53:17 EST


On Tue, Sep 22, 2015 at 10:19 AM, Thomas Graf <tgraf@xxxxxxx> wrote:
> On 09/21/15 at 04:03pm, Eric Dumazet wrote:
>> What I said is :
>>
>> In @head you already have the correct nulls value, from hash table.
>>
>> You do not need to recompute this value, and/or test if hash table chain
>> is empty.
>>
>> If hash bucket is empty, it contains the appropriate NULLS value.
>>
>> If you are paranoiac add this debugging check :
>>
>> if (rht_is_a_nulls(head))
>> BUG_ON(head != (struct rhash_head *)rht_marker(ht, new_hash));
>>
>>
>> Therefore, simply fix the bug and unnecessary code with :
>
> You are absolutely right Eric. Do you want to revise your patch Dmitry?
> Eric's proposed fix absolutely the best way to fix this.

Mailed v2 of the patch.

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