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    Subjectx86/NUMA: Reason for ignoring too small NUMA nodes?
    Hi Andi,

    while experimenting with a system with a memory-less NUMA node I
    stumbled upon code in the Linux kernel which ignores nodes containing
    less than a certain amount of RAM, obviously to fix systems with a buggy
    BIOS.
    Can you elaborate on this? What kind of incorrect entry have you seen?
    To correctly map the memory less node I did a patch to accept at least
    nodes with exactly zero bytes of memory (read: no SRAT memory entry),
    was this special condition also present in the buggy machines?
    Another comments reads:
    /*
    * Don't confuse VM with a node that doesn't have the
    * minimum amount of memory:
    */
    Is that still a valid statement? How can the VM get confused by a node
    with already exhausted memory resources?
    (found in arch/x86/mm/{srat,numa}_64.c)

    I'd be grateful for some hints!

    Thanks,
    Andre.

    --
    Andre Przywara
    AMD-Operating System Research Center (OSRC), Dresden, Germany
    Tel: +49 351 448 3567 12
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