From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sagi Grimberg <sagi-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org>
Subject: Re: RDMA Read: Local protection error
Date: Sun, 29 May 2016 10:02:53 +0300
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>> Sagi,
>> I'm wondering if allocation from ZONE_DMA is the right way to
>> replace ZONE_NORMAL allocations.
>>
>> I don't remember if memory compaction works on ZONE_DMA and it makes
>> me nervous to think about long and multiple alloc/dealloc MR scenario.
>
> ZONE_DMA is a 16M memory segment used for legacy devices of the PC/AT era
> (such as floppy drivers). Please do not use it.

Really? It's used all over the stack...

So the suggestion is to restrict the allocation does not
cross the page boundary (which can easily be done with making
MLX4_MR_PAGES_ALIGN be PAGE_SIZE or larger than PAGE_SIZE/2)?
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