RE: [PATCH v3 2/2] mm: fix the handling Non-LRU pages returned by follow_page

[Wang, Haiyue]

> -----Original Message-----
> From: Huang, Ying <ying.huang@xxxxxxxxx>
> Sent: Monday, August 15, 2022 09:40
> To: Wang, Haiyue <haiyue.wang@xxxxxxxxx>
> Cc: linux-mm@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx; david@xxxxxxxxxx;
> linmiaohe@xxxxxxxxxx; songmuchun@xxxxxxxxxxxxx; naoya.horiguchi@xxxxxxxxx; alex.sierra@xxxxxxx; Felix
> Kuehling <Felix.Kuehling@xxxxxxx>; Alistair Popple <apopple@xxxxxxxxxx>
> Subject: Re: [PATCH v3 2/2] mm: fix the handling Non-LRU pages returned by follow_page
> 
> Haiyue Wang <haiyue.wang@xxxxxxxxx> writes:
> 
> > The page returned by follow_page with 'FOLL_GET' has get_page called, so
> 
> Better to add "()" after function name to improve the readability, for
> example, "follow_page()".

Got it, didn't notice this. ;-)

> 
> > it needs to call put_page for handling the reference count correctly.
> >
> > And as David reviewed, "device pages are never PageKsm pages". Drop this
> > zone device page check for break_ksm.
> >
> > Fixes: 3218f8712d6b ("mm: handling Non-LRU pages returned by vm_normal_pages")
> 
> In your patch description, I cannot find how the above commit is related
> to the bug you fixed.  Add some words about that?

The first commit session, but maybe not very clear, will try to add more words
In v4.

> 
> Best Regards,
> Huang, Ying
> 
> > Signed-off-by: Haiyue Wang <haiyue.wang@xxxxxxxxx>
> > ---
> >  mm/huge_memory.c |  4 ++--
> >  mm/ksm.c         | 12 +++++++++---
> >  mm/migrate.c     | 10 +++++++---
> >  3 files changed, 18 insertions(+), 8 deletions(-)
> >