Re: [RFC PATCH v4 1/6] migrate: Allow migrate_misplaced_folio_prepare() to accept a NULL VMA.

[SeongJae Park]

On Fri, 11 Apr 2025 18:11:06 -0400 Gregory Price <gourry@xxxxxxxxxx> wrote:

> migrate_misplaced_folio_prepare() may be called on a folio without
> a VMA, and so it must be made to accept a NULL VMA.

The comment of the function says "Must be called with the PTL still held".  I
understand it is not needed for NULL VMA case because it is for unmapped
folios?  If I'm understanding correctly, could you please also clarify such
details including when NULL VMA case happens and if locking requirement is
changed, on the comment?


Thanks,
SJ

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