From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x242.google.com (mail-qt0-x242.google.com [IPv6:2607:f8b0:400d:c0d::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 41VM9z2WfmzF3Hw for ; Tue, 17 Jul 2018 23:50:47 +1000 (AEST) Received: by mail-qt0-x242.google.com with SMTP id y5-v6so876956qti.12 for ; Tue, 17 Jul 2018 06:50:47 -0700 (PDT) Sender: Ram Pai From: Ram Pai To: shuahkh@osg.samsung.com, linux-kselftest@vger.kernel.org Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, mingo@redhat.com, dave.hansen@intel.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, linuxram@us.ibm.com, fweimer@redhat.com, msuchanek@suse.de, aneesh.kumar@linux.vnet.ibm.com Subject: [PATCH v14 20/22] selftests/vm: testcases must restore pkey-permissions Date: Tue, 17 Jul 2018 06:49:23 -0700 Message-Id: <1531835365-32387-21-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1531835365-32387-1-git-send-email-linuxram@us.ibm.com> References: <1531835365-32387-1-git-send-email-linuxram@us.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Generally the signal handler restores the state of the pkey register before returning. However there are times when the read/write operation can legitamely fail without invoking the signal handler. Eg: A sys_read() operaton to a write-protected page should be disallowed. In such a case the state of the pkey register is not restored to its original state. Test cases may not remember to restoring the key register state. During cleanup generically restore the key permissions. cc: Dave Hansen cc: Florian Weimer Signed-off-by: Ram Pai --- tools/testing/selftests/vm/protection_keys.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c index 8a6afdd..ea3cf04 100644 --- a/tools/testing/selftests/vm/protection_keys.c +++ b/tools/testing/selftests/vm/protection_keys.c @@ -1476,8 +1476,13 @@ void run_tests_once(void) pkey_tests[test_nr](ptr, pkey); dprintf1("freeing test memory: %p\n", ptr); free_pkey_malloc(ptr); + + /* restore the permission on the key after use */ + pkey_access_allow(pkey); + pkey_write_allow(pkey); sys_pkey_free(pkey); + dprintf1("pkey_faults: %d\n", pkey_faults); dprintf1("orig_pkey_faults: %d\n", orig_pkey_faults); -- 1.7.1