Re: [PATCH v3 3/6] mm: hugetlb: fix a race between freeing and dissolving the page

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.

/*
 * Move PageHWPoison flag from head page to the raw error page,
 * which makes any subpages rather than the error page reusable.

-- 2.11.0