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From:   Pavel Tatashin <pasha.tatashin@oracle.com>
Date:   Sun, 1 Jul 2018 22:18:08 -0400
Message-ID: <CAGM2rebY1_-3hvp_+kqF==nLawC0FN6Q1J5X5pm5qxHdDJzjiQ@mail.gmail.com>
Subject: Re: [PATCH v3 1/2] mm/sparse: add sparse_init_nid()
To:     bhe@redhat.com
Cc:     Steven Sistare <steven.sistare@oracle.com>,
        Daniel Jordan <daniel.m.jordan@oracle.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        kirill.shutemov@linux.intel.com, Michal Hocko <mhocko@suse.com>,
        Linux Memory Management List <linux-mm@kvack.org>,
        dan.j.williams@intel.com, jack@suse.cz, jglisse@redhat.com,
        Souptick Joarder <jrdr.linux@gmail.com>,
        gregkh@linuxfoundation.org, Vlastimil Babka <vbabka@suse.cz>,
        Wei Yang <richard.weiyang@gmail.com>, dave.hansen@intel.com,
        rientjes@google.com, mingo@kernel.org, osalvador@techadventures.net
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> Here, I think it might be not right to jump to 'failed' directly if one
> section of the node failed to populate memmap. I think the original code
> is only skipping the section which memmap failed to populate by marking
> it as not present with "ms->section_mem_map = 0".
>

Hi Baoquan,

Thank you for a careful review. This is an intended change compared to
the original code. Because we operate per-node now, if we fail to
allocate a single section, in this node, it means we also will fail to
allocate all the consequent sections in the same node and no need to
check them anymore. In the original code we could not simply bailout,
because we still might have valid entries in the following nodes.
Similarly, sparse_init() will call sparse_init_nid() for the next node
even if previous node failed to setup all the memory.

Pavel