On Tue 13-11-18 20:38:16, Yongkai Wu wrote: > It is better to keep page mapping info when free_huge_page() hit the > VM_BUG_ON_PAGE, > so we can get more infomation from the coredump for further analysis. The patch seems to be whitespace damaged. Put that aside, have you actually seen a case where preservning the page state would help to nail down any bug. I am not objecting to the patch, it actually makes some sense to me, I am just curious about a background motivation. > Signed-off-by: Yongkai Wu <nic_w@xxxxxxx> > --- > mm/hugetlb.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index c007fb5..ba693bb 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1248,10 +1248,11 @@ void free_huge_page(struct page *page) > (struct hugepage_subpool *)page_private(page); > bool restore_reserve; > > + VM_BUG_ON_PAGE(page_count(page), page); > + VM_BUG_ON_PAGE(page_mapcount(page), page); > + > set_page_private(page, 0); > page->mapping = NULL; > - VM_BUG_ON_PAGE(page_count(page), page); > - VM_BUG_ON_PAGE(page_mapcount(page), page); > restore_reserve = PagePrivate(page); > ClearPagePrivate(page); > > -- > 1.8.3.1 -- Michal Hocko SUSE Labs
