X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=mm%2Frmap.c;h=89770bd25f31be71877813a292793fcc62e01116;hb=ca775c629a366ded01aae69da8410f70aaf85de1;hp=9827409eb7c7ea4026e27b34fdaceacd909cabc3;hpb=befc9e10d64f93472aff0b0280968f447f5402df;p=powerpc.git

diff --git a/mm/rmap.c b/mm/rmap.c
index 9827409eb7..89770bd25f 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -539,27 +539,6 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma)
 		goto out_unmap;
 	}
 
-	/*
-	 * Don't pull an anonymous page out from under get_user_pages.
-	 * GUP carefully breaks COW and raises page count (while holding
-	 * page_table_lock, as we have here) to make sure that the page
-	 * cannot be freed.  If we unmap that page here, a user write
-	 * access to the virtual address will bring back the page, but
-	 * its raised count will (ironically) be taken to mean it's not
-	 * an exclusive swap page, do_wp_page will replace it by a copy
-	 * page, and the user never get to see the data GUP was holding
-	 * the original page for.
-	 *
-	 * This test is also useful for when swapoff (unuse_process) has
-	 * to drop page lock: its reference to the page stops existing
-	 * ptes from being unmapped, so swapoff can make progress.
-	 */
-	if (PageSwapCache(page) &&
-	    page_count(page) != page_mapcount(page) + 2) {
-		ret = SWAP_FAIL;
-		goto out_unmap;
-	}
-
 	/* Nuke the page table entry. */
 	flush_cache_page(vma, address, page_to_pfn(page));
 	pteval = ptep_clear_flush(vma, address, pte);