From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x243.google.com (mail-qt0-x243.google.com [IPv6:2607:f8b0:400d:c0d::243]) (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 3x9CPG0gwPzDqmD for ; Sun, 16 Jul 2017 14:00:02 +1000 (AEST) Received: by mail-qt0-x243.google.com with SMTP id w12so14717274qta.2 for ; Sat, 15 Jul 2017 21:00:01 -0700 (PDT) Sender: Ram Pai From: Ram Pai To: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, dave.hansen@intel.com, hbabu@us.ibm.com, linuxram@us.ibm.com, arnd@arndb.de, akpm@linux-foundation.org, corbet@lwn.net, mingo@redhat.com, mhocko@kernel.org Subject: [RFC v6 48/62] selftest/vm: clear the bits in shadow reg when a pkey is freed. Date: Sat, 15 Jul 2017 20:56:50 -0700 Message-Id: <1500177424-13695-49-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1500177424-13695-1-git-send-email-linuxram@us.ibm.com> References: <1500177424-13695-1-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: , When a key is freed, the key is no more effective. Clear the bits corresponding to the pkey in the shadow register. Otherwise it will carry some spurious bits which can trigger false-positive asserts. Signed-off-by: Ram Pai --- tools/testing/selftests/vm/protection_keys.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c index 0f2d1ce..4f4ce36 100644 --- a/tools/testing/selftests/vm/protection_keys.c +++ b/tools/testing/selftests/vm/protection_keys.c @@ -582,6 +582,9 @@ int alloc_pkey(void) int sys_pkey_free(unsigned long pkey) { int ret = syscall(SYS_pkey_free, pkey); + + if (!ret) + shadow_pkey_reg &= reset_bits(pkey, PKEY_DISABLE_ACCESS); dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret); return ret; } -- 1.7.1