Re: [PATCH 2/2] mm: compaction: fix the possible deadlock when isolating hugetlb pages

[Mike Kravetz]

On 03/14/23 12:11, Baolin Wang wrote:
> On 3/14/2023 1:08 AM, Mike Kravetz wrote:
> > On 03/13/23 18:37, Baolin Wang wrote:
> > 
> > It would seem that the pfn of a hugetlb page would always be a multiple of
> > COMPACT_CLUSTER_MAX so we would drop the lock.  However, I am not sure if
> > that is ALWAYS true and would prefer something like the code you suggested.
> 
> Well, this is not always true, suppose the CONT-PTE hugetlb on ARM arch,
> which contains 16 contiguous normal pages.
> 

Right.  I keep forgetting about the CONT-* page sizes on arm :(

In any case, I think explicitly dropping the lock as you have done is a
good idea.

Feel free to add,

Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
-- 
Mike Kravetz