Re: [PATCH v3 1/2] mm: migration: fix the FOLL_GET failure on following huge page

[Huang, Ying]

Haiyue Wang <haiyue.wang@xxxxxxxxx> writes:

> Not all huge page APIs support FOLL_GET option, so the __NR_move_pages

move_pages() is a syscall, so you can just call it move_pages(), or
move_pages() syscall.

> will fail to get the page node information for huge page.
                                                 ~~~~~~~~~
some huge pages?

> This is an temporary solution to mitigate the racing fix.

Why is it "racing fix"?  This isn't a race condition fix.

Best Regards,
Huang, Ying

> After supporting follow huge page by FOLL_GET is done, this fix can be
> reverted safely.
>
> Fixes: 4cd614841c06 ("mm: migration: fix possible do_pages_stat_array racing with memory offline")
> Signed-off-by: Haiyue Wang <haiyue.wang@xxxxxxxxx>

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