| Message ID | 20210104065843.5658-6-songmuchun@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/6] mm: migrate: do not migrate HugeTLB page whose refcount is one | expand |
On 1/3/21 10:58 PM, Muchun Song wrote: > The page_huge_active() can be called from scan_movable_pages() which > do not hold a reference count to the HugeTLB page. So when we call > page_huge_active() from scan_movable_pages(), the HugeTLB page can > be freed parallel. Then we will trigger a BUG_ON which is in the > page_huge_active() when CONFIG_DEBUG_VM is enabled. Just remove the > VM_BUG_ON_PAGE. > > Fixes: 7e1f049efb86 ("mm: hugetlb: cleanup using paeg_huge_active()") > Signed-off-by: Muchun Song <songmuchun@bytedance.com> > --- > mm/hugetlb.c | 1 - > 1 file changed, 1 deletion(-) Thanks! Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 5c2f64f53177..4c8631114e88 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1360,7 +1360,6 @@ struct hstate *size_to_hstate(unsigned long size) */ bool page_huge_active(struct page *page) { - VM_BUG_ON_PAGE(!PageHuge(page), page); return PageHead(page) && PagePrivate(&page[1]); }
The page_huge_active() can be called from scan_movable_pages() which do not hold a reference count to the HugeTLB page. So when we call page_huge_active() from scan_movable_pages(), the HugeTLB page can be freed parallel. Then we will trigger a BUG_ON which is in the page_huge_active() when CONFIG_DEBUG_VM is enabled. Just remove the VM_BUG_ON_PAGE. Fixes: 7e1f049efb86 ("mm: hugetlb: cleanup using paeg_huge_active()") Signed-off-by: Muchun Song <songmuchun@bytedance.com> --- mm/hugetlb.c | 1 - 1 file changed, 1 deletion(-)