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Reply-To: sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search
 criteria
To:     Uladzislau Rezki <urezki@gmail.com>
Cc:     Dave Hansen <dave.hansen@intel.com>, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20190729232139.91131-1-sathyanarayanan.kuppuswamy@linux.intel.com>
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 <20190730223400.hzsyjrxng2s5gk4u@pc636>
From:   sathyanarayanan kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
Organization: Intel
Message-ID: <63e48375-afa4-4ab6-240d-1633d7cc9ea4@linux.intel.com>
Date:   Tue, 30 Jul 2019 15:37:33 -0700
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On 7/30/19 3:34 PM, Uladzislau Rezki wrote:
> Hello, Sathyanarayanan.
>
>> I agree with Dave. I don't think this issue is related to NUMA. The problem
>> here is about the logic we use to find appropriate vm_area that satisfies
>> the offset and size requirements of pcpu memory allocator.
>>
>> In my test case, I can reproduce this issue if we make request with offset
>> (ffff000000) and size (600000).
>>
> Just to clarify, does it mean that on your setup you have only one area with the
> 600000 size and 0xffff000000 offset?
No, its 2 areas. with offset (0, ffff000000) and size (a00000, 600000).
>
> Thank you.
>
> --
> Vlad Rezki
>
-- 
Sathyanarayanan Kuppuswamy
Linux kernel developer