From 14128d757776d036a898fd51e858c15014270a1d Mon Sep 17 00:00:00 2001
From: Ram Pai <linuxram@us.ibm.com>
Date: Mon, 22 Jan 2018 10:52:12 -0800
Subject: [PATCH 25/30] selftests/vm: detect write violation on a mapped
 access-denied-key page

References: FATE#322447, bsc#1078248
Patch-mainline: submitted https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-January/168234.html

detect write-violation on a page to which access-disabled
key is associated much after the page is mapped.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 tools/testing/selftests/vm/protection_keys.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index f90a8b61d133..3e9e36d48706 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -1059,6 +1059,18 @@ void test_write_of_access_disabled_region(int *ptr, u16 pkey)
 	*ptr = __LINE__;
 	expected_pkey_fault(pkey);
 }
+
+void test_write_of_access_disabled_region_with_page_already_mapped(int *ptr,
+			u16 pkey)
+{
+	*ptr = __LINE__;
+	dprintf1("disabling access; after accessing the page, "
+		" to PKEY[%02d], doing write\n", pkey);
+	pkey_access_deny(pkey);
+	*ptr = __LINE__;
+	expected_pkey_fault(pkey);
+}
+
 void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
 {
 	int ret;
@@ -1343,6 +1355,7 @@ void (*pkey_tests[])(int *ptr, u16 pkey) = {
 	test_write_of_write_disabled_region,
 	test_write_of_write_disabled_region_with_page_already_mapped,
 	test_write_of_access_disabled_region,
+	test_write_of_access_disabled_region_with_page_already_mapped,
 	test_kernel_write_of_access_disabled_region,
 	test_kernel_write_of_write_disabled_region,
 	test_kernel_gup_of_access_disabled_region,
-- 
2.13.6