On Tue, Jan 12, 2021 at 6:02 PM Michal Hocko <[email protected]> wrote: > > On Sun 10-01-21 20:40:14, Muchun Song wrote: > [...] > > @@ -1770,6 +1788,14 @@ int dissolve_free_huge_page(struct page *page) > > int nid = page_to_nid(head); > > if (h->free_huge_pages - h->resv_huge_pages == 0) > > goto out; > > + > > + /* > > + * We should make sure that the page is already on the free > > list > > + * when it is dissolved. > > + */ > > + if (unlikely(!PageHugeFreed(head))) > > + goto out; > > + > > Do you really want to report EBUSY in this case? This doesn't make much > sense to me TBH. I believe you want to return 0 same as when you race > and the page is no longer PageHuge.
Return 0 is wrong. Because the page is not freed to the buddy allocator. IIUC, dissolve_free_huge_page returns 0 when the page is already freed to the buddy allocator. Right? > > > /* > > * Move PageHWPoison flag from head page to the raw error > > page, > > * which makes any subpages rather than the error page > > reusable. > > -- > > 2.11.0 > > -- > Michal Hocko > SUSE Labs
