diff options
| -rw-r--r-- | mm/memory.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c index 601159a46ab..160f5b503ea 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1577,7 +1577,14 @@ gotten: entry = mk_pte(new_page, vma->vm_page_prot); entry = maybe_mkwrite(pte_mkdirty(entry), vma); lazy_mmu_prot_update(entry); - ptep_establish(vma, address, page_table, entry); + /* + * Clear the pte entry and flush it first, before updating the + * pte with the new entry. This will avoid a race condition + * seen in the presence of one thread doing SMC and another + * thread doing COW. + */ + ptep_clear_flush(vma, address, page_table); + set_pte_at(mm, address, page_table, entry); update_mmu_cache(vma, address, entry); lru_cache_add_active(new_page); page_add_new_anon_rmap(new_page, vma, address); |