323 	/* Establish a guard page at the end of the mapping. */  in TEST_F()
327 	/* Check that both guard pages result in SIGSEGV. */  in TEST_F()
331 	/* Remove the first guard page. */  in TEST_F()
337 	/* Remove the last guard page. */  in TEST_F()
346 	 *  these be faulted in, so this also tests that we can install guard  in TEST_F()
351 	/* Make sure they are all guard pages. */  in TEST_F()
365 	/* Remove guard pages. */  in TEST_F()
376 	 * Now remove all guard pages, make sure we don't remove existing  in TEST_F()
429 	 * Now mark the whole range as guard pages and make sure all VMAs are as  in TEST_F()
543 	/* We want guard markers at start/end of each VMA. */  in TEST_F()
573 	/* Now guard in one step. */  in TEST_F()
614 /* Assert that unmapping ranges does not leave guard markers behind. */
624 	/* Guard first and last pages. */  in TEST_F()
652 /* Assert that mprotect() operations have no bearing on guard markers. */
663 	/* Guard the middle of the range. */  in TEST_F()
678 	/* Make sure we can guard again without issue.*/  in TEST_F()
700 /* Split and merge VMAs and make sure guard pages still behave. */
711 	/* Guard the whole range. */  in TEST_F()
759 	/* Now make sure guard pages are established. */  in TEST_F()
768 	/* Now guard everything again. */  in TEST_F()
831 /* Assert that MADV_DONTNEED does not remove guard markers. */
849 	/* Guard every other page. */  in TEST_F()
860 	/* Check to ensure guard markers are still in place. */  in TEST_F()
892 /* Assert that mlock()'ed pages work correctly with guard markers. */
913 	/* Now try to guard, should fail with EINVAL. */  in TEST_F()
920 	/* Guard first half of range, should now succeed. */  in TEST_F()
923 	/* Make sure guard works. */  in TEST_F()
937 	 * Now lock the latter part of the range. We can't lock the guard pages,  in TEST_F()
944 	 * Now remove guard pages, we permit mlock()'d ranges to have guard  in TEST_F()
949 	/* Now check that no guard pages remain. */  in TEST_F()
962  * guard markers where possible.
976 	/* Place guard markers at both ends of the 5 page span. */  in TEST_F()
980 	/* Make sure the guard pages are in effect. */  in TEST_F()
993 	/* Make sure the guard markers are retained. */  in TEST_F()
1006  * guard markers where possible.
1008  * Expanding should retain guard pages, only now in different position. The user
1009  * will have to remove guard pages manually to fix up (they'd have to do the
1024 	/* Place guard markers at both ends of the 5 page span. */  in TEST_F()
1037 	 * Make sure the guard markers are retained in their original positions.  in TEST_F()
1052 	 * Again, make sure the guard markers are retained in their original positions.  in TEST_F()
1058 	 * A real user would have to remove guard markers, but would reasonably  in TEST_F()
1060 	 * guard markers.  in TEST_F()
1068  * guard markers where possible.
1085 	/* Place guard markers at both ends of the 5 page span. */  in TEST_F()
1097 	/* We expect the guard marker at the start to be retained... */  in TEST_F()
1100 	/* ...But remaining pages will not have guard markers. */  in TEST_F()
1108 	 * As with expansion, a real user would have to remove guard pages and  in TEST_F()
1120 	/* Again, we expect the guard marker at the start to be retained... */  in TEST_F()
1123 	/* ...But remaining pages will not have guard markers. */  in TEST_F()
1136  * retain guard pages.
1150 	/* Establish guard pages in the first 5 pages. */  in TEST_F()
1191  * and then guard and unguard the range.
1228 		/* Establish guard pages across the whole range. */  in TEST_F()
1234 		 * By removing the guard pages, the page tables will be  in TEST_F()
1285 	/* Guard the first 5 pages. */  in TEST_F()
1293 		/* Guard will have been wiped. */  in TEST_F()
1307 	/* Guard markers should be in effect.*/  in TEST_F()
1319 /* Ensure that MADV_FREE retains guard entries as expected. */
1334 	/* Guard range. */  in TEST_F()
1347 	/* This should leave the guard markers in place. */  in TEST_F()
1369 	/* Guard range. */  in TEST_F()
1384 /* Ensure that MADV_COLD, MADV_PAGEOUT do not remove guard markers. */
1396 	/* Guard range. */  in TEST_F()
1406 	/* Now mark cold. This should have no impact on guard markers. */  in TEST_F()
1430 /* Ensure that guard pages do not break userfaultd. */
1480 	/* Guard the range. This should not trigger the uffd. */  in TEST_F()
1498  * aggressively read-ahead, then install guard regions and assert that it
1501  * We page out using MADV_PAGEOUT before checking guard regions so we drop page
1524 	/* Mark every other page a guard page. */  in TEST_F()
1547 	/* Now remove guard pages. */  in TEST_F()
1558  * Check that file-backed mappings implement guard regions with MAP_PRIVATE
1580 	/* Install guard regions in every other page in the shared mapping. */  in TEST_F()
1594 	/* Install guard regions in every other page in the private mapping. */  in TEST_F()
1608 	/* Remove guard regions from shared mapping. */  in TEST_F()
1618 	/* Remove guard regions from private mapping. */  in TEST_F()
1661 		/* Ensure guard regions as expected. */  in TEST_F()
1667 	/* Remove the guard regions altogether. */  in TEST_F()
1677 	 * As we removed guard regions, the private pages from the first 5 will  in TEST_F()
1703 /* Test that guard regions established over a read-only mapping function correctly. */
1736 	/* Assert that the guard regions are in place.*/  in TEST_F()
1743 	/* Remove guard regions. */  in TEST_F()
1794 	/* Finally, ensure that guard regions are intact as expected. */  in TEST_F()
1840 	/* Here the guard regions will remain intact. */  in TEST_F()
1851 	/* Again, guard pages will remain intact. */  in TEST_F()
1876 	/* Install a guard region in the middle of the mapping. */  in TEST_F()
1886 	 * Where * is data and x is the guard region.  in TEST_F()
1900 	/* Ensure guard regions remain. */  in TEST_F()
1907 	/* Now remove guard region throughout. */  in TEST_F()
1921  * Ensure that a memfd works correctly with guard regions, that we can write
1922  * seal it then open the mapping read-only and still establish guard regions
1923  * within, remove those guard regions and have everything work correctly.
1973 	/* Now remove guard regions. */  in TEST_F()
1991  * Since we are now permitted to establish guard regions in read-only anonymous
1993  * use, test that guard regions function with a mapping to the anonymous zero
2023 	/* Now remove all guard regions. */  in TEST_F()
2040  * Assert that /proc/$pid/pagemap correctly identifies guard region ranges.
2056 	/* Read from pagemap, and assert no guard regions are detected. */  in TEST_F()
2065 	/* Install a guard region in every other page. */  in TEST_F()
2072 	/* Re-read from pagemap, and assert guard regions are detected. */  in TEST_F()
2086  * Assert that PAGEMAP_SCAN correctly reports guard region ranges.
2114 	/* Install a guard region in every other page. */  in TEST_F()
2128 	/* Re-read from pagemap, and assert guard regions are detected. */  in TEST_F()