| Message ID | 20210115124942.46403-6-songmuchun@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix some bugs about HugeTLB code | expand |
On Fri, Jan 15, 2021 at 08:49:42PM +0800, 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> > Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> > Acked-by: Michal Hocko <mhocko@suse.com> > Cc: stable@vger.kernel.org Reviewed-by: Oscar Salvador <osalvador@suse.de>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f2cef3cf1f85..2d671f3743f5 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1360,8 +1360,7 @@ 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]); + return PageHeadHuge(page) && PagePrivate(&page[1]); } /* never called for tail page */
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> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: stable@vger.kernel.org --- mm/hugetlb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)