diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1cc4a5f4791e..811d19b5c4f6 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2206,9 +2206,12 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = pte_wrprotect(entry); if (!young) entry = pte_mkold(entry); - /* NOTE: this may set soft-dirty too on some archs */ - if (dirty) - entry = pte_mkdirty(entry); + /* + * NOTE: we don't do pte_mkdirty when dirty==true + * because it breaks sparc64 which can sigsegv + * random process. Need to revisit when we figure + * out what is special with sparc64. + */ if (soft_dirty) entry = pte_mksoft_dirty(entry); if (uffd_wp) @@ -2455,7 +2458,16 @@ static void __split_huge_page_tail(struct page *head, int tail, page_tail); page_tail->mapping = head->mapping; page_tail->index = head->index + tail; - page_tail->private = 0; + + /* + * page->private should not be set in tail pages with the exception + * of swap cache pages that store the swp_entry_t in tail pages. + * Fix up and warn once if private is unexpectedly set. + */ + if (!folio_test_swapcache(page_folio(head))) { + VM_WARN_ON_ONCE_PAGE(page_tail->private != 0, page_tail); + page_tail->private = 0; + } /* Page flags must be visible before we make the page non-compound. */ smp_wmb(); |