From 4da5eda0dca9730f59f391230304526ab4bffec7 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Fri, 23 Jun 2006 02:03:04 -0700 Subject: [PATCH] [PATCH] Page Migration: Make do_swap_page redo the fault It is better to redo the complete fault if do_swap_page() finds that the page is not in PageSwapCache() because the page migration code may have replaced the swap pte already with a pte pointing to valid memory. do_swap_page() may interpret an invalid swap entry without this patch because we do not reload the pte if we are looping back. The page migration code may already have reused the swap entry referenced by our local swp_entry. Signed-off-by: Christoph Lameter Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index 0ec7bc6442..7e3683fd4f 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1879,7 +1879,6 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, goto out; entry = pte_to_swp_entry(orig_pte); -again: page = lookup_swap_cache(entry); if (!page) { swapin_readahead(entry, address, vma); @@ -1903,12 +1902,6 @@ again: mark_page_accessed(page); lock_page(page); - if (!PageSwapCache(page)) { - /* Page migration has occured */ - unlock_page(page); - page_cache_release(page); - goto again; - } /* * Back out if somebody else already faulted in this pte. -- 2.39.5