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Date:   Thu, 6 Jun 2019 07:29:33 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Bharath Vedartham <linux.bhar@gmail.com>
Cc:     akpm@linux-foundation.org, vbabka@suse.cz, rientjes@google.com,
        khalid.aziz@oracle.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: Remove VM_BUG_ON in __alloc_pages_node
Message-ID: <20190606052933.GA8575@dhcp22.suse.cz>
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On Wed 05-06-19 21:25:01, Bharath Vedartham wrote:
> IMO the reason why a lot of failures must not have occured in the past
> might be because the programs which use it use stuff like cpu_to_node or
> have checks for nid.
> If one day we do get a program which passes an invalid node id without
> VM_BUG_ON enabled, it might get weird.

It will blow up on a NULL NODE_DATA and it will be quite obvious what
that was so I wouldn't lose any sleep over that. I do not think we have
any directly user controlable way to provide a completely ad-hoc numa
node for an allocation.

-- 
Michal Hocko
SUSE Labs