Re: [PATCH v3 3/5] mm/hugetlb: fix getting refcount 0 page in hugetlb_fault()

2014-10-07 Thread Naoya Horiguchi
On Mon, Sep 29, 2014 at 09:52:24PM -0700, Hugh Dickins wrote: > On Mon, 15 Sep 2014, Naoya Horiguchi wrote: > > When running the test which causes the race as shown in the previous patch, > > we can hit the BUG "get_page() on refcount 0 page" in hugetlb_fault(). > > Two minor comments... > > > @@

Re: [PATCH v3 3/5] mm/hugetlb: fix getting refcount 0 page in hugetlb_fault()

2014-09-29 Thread Hugh Dickins
On Mon, 15 Sep 2014, Naoya Horiguchi wrote: > When running the test which causes the race as shown in the previous patch, > we can hit the BUG "get_page() on refcount 0 page" in hugetlb_fault(). Two minor comments... > @@ -3192,22 +3208,19 @@ int hugetlb_fault(struct mm_struct *mm, struct > vm_a

[PATCH v3 3/5] mm/hugetlb: fix getting refcount 0 page in hugetlb_fault()

2014-09-15 Thread Naoya Horiguchi
When running the test which causes the race as shown in the previous patch, we can hit the BUG "get_page() on refcount 0 page" in hugetlb_fault(). This race happens when pte turns into migration entry just after the first check of is_hugetlb_entry_migration() in hugetlb_fault() passed with false.