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Message-ID: <0e99b72c-c3d9-424e-8efe-af750da69ebf@ustc.edu>
Date: Mon, 29 Jan 2024 14:15:00 +0800
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Subject: Re: [PATCH] mempolicy: check home_node is in the nodes of policy
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20240126132240.24518-1-luochunsheng@ustc.edu>
 <20240128002942.b0dbede1fcc4b80d2a398d15@linux-foundation.org>
From: ustc <luochunsheng@ustc.edu>
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For example,  In a system with NUMA nodes 0,1,2,3, i mbind process to 
node 0-2 and set home_node to node 3, it will not be allocated from node 
3, then from node closer to node 3. But i think home_node should be set 
directly from node 0-2, which makes more sense. So i think it needs to 
return failure to prompt user.


On 2024/1/28 16:29, Andrew Morton wrote:
> On Fri, 26 Jan 2024 08:22:40 -0500 Chunsheng Luo <luochunsheng@ustc.edu> wrote:
>
>> set_mempolicy_home_node should be used after setting the memory
>> policy. If the home_node isn't in the nodes of policy, we should
>> return failure to avoid misunderstanding.
> Thanks.  Under what circumstances does userspace trigger this issue?
>