Re: [PATCH] mm: fix missing wake-up event for FSDAX pages

2022-07-04 Thread Muchun Song
On Mon, Jul 04, 2022 at 11:38:16AM +0100, Matthew Wilcox wrote: > On Mon, Jul 04, 2022 at 03:40:54PM +0800, Muchun Song wrote: > > FSDAX page refcounts are 1-based, rather than 0-based: if refcount is > > 1, then the page is freed. The FSDAX pages can be pinned through GUP, > > then they will be u

Re: [PATCH] mm: fix missing wake-up event for FSDAX pages

2022-07-04 Thread Matthew Wilcox
On Mon, Jul 04, 2022 at 03:40:54PM +0800, Muchun Song wrote: > FSDAX page refcounts are 1-based, rather than 0-based: if refcount is > 1, then the page is freed. The FSDAX pages can be pinned through GUP, > then they will be unpinned via unpin_user_page() using a folio variant > to put the page, h

[PATCH] mm: fix missing wake-up event for FSDAX pages

2022-07-04 Thread Muchun Song
FSDAX page refcounts are 1-based, rather than 0-based: if refcount is 1, then the page is freed. The FSDAX pages can be pinned through GUP, then they will be unpinned via unpin_user_page() using a folio variant to put the page, however, folio variants did not consider this special case, the result