From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELuYs/aiBT06pbBQbruOd8PM7yTklPSH7XIPrKnhe9h+VD9SaE05du3fRt0QjBcyNRb+x+Uv ARC-Seal: i=1; a=rsa-sha256; t=1521238791; cv=none; d=google.com; s=arc-20160816; b=ytE4UYhEahM3k49GQnbcnpnFdOU7j2yz1znJR+RWY5YkQlFJewQEOMlmbsAX5QsxPd z5/Ku6gNduahQlM1VGPFnBwg+rRR9T50a1/QKFUy8623HeddiLgXMfwcNE6SG4mrxlVs 7eLcE4cnCfcPoT8uWfKuKz5wjnZlk9rODb45XaIXSZouylvfiFQbTkz+OAfc216OKd/i J5LyKlc4Q5WWNMBPq4i4ITtyIH7Lf+VU43H+GCwVODfPcMyJFwshuRO69UbGVa7AW9jE Zom/Nzvv7d4Mn7FyC/Gg2zyQZGnfbtlBrkZhfa8QdK1D/grm8aBjOapce2R8pag8kIhw 8rkA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:from:cc:references:to:subject:arc-authentication-results; bh=lZmtn+5jLJIJihqPTnzgA2yTPiVhAgF1rwrw4l7QcaY=; b=PU+tsxkqhX+l7EtTN13BJymzvvpPqEtscTjIHFIo1PNl7V3GTjxdyZPlgeGb81wLNn 5Lh4C3n5KybKQUw4c7hYdlJBPFSk2wcPsVHt6FrLmzOFnboapUuNbcVZWl4/fV4nJe28 flL0sbclF7AwUYHTSHxOvHjLh00tbwjj7QjZ+T1gk3X8KzrsDtbltwamz9mN4k4tXfWF rU8g953sapAdBMJxw/LfoCubZju5htfTpEFQRGTaXStU33g4cAxSi0sRDRyDY7TA9D50 K1+SuQJ8Ip5jcJXTWwxCjbLDX/znVacJovclqpOy7Eo3tsC4w5BMIB1WtXEm4F6uTvhR 1YAA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kselftest-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kselftest-owner@vger.kernel.org Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kselftest-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kselftest-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751562AbeCPWTW (ORCPT ); Fri, 16 Mar 2018 18:19:22 -0400 Received: from mga12.intel.com ([192.55.52.136]:54176 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750915AbeCPWTV (ORCPT ); Fri, 16 Mar 2018 18:19:21 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,317,1517904000"; d="scan'208";a="25371125" Subject: Re: [PATCH v12 11/22] selftests/vm: pkey register should match shadow pkey To: Ram Pai , shuahkh@osg.samsung.com, linux-kselftest@vger.kernel.org References: <1519264541-7621-1-git-send-email-linuxram@us.ibm.com> <1519264541-7621-12-git-send-email-linuxram@us.ibm.com> Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, akpm@linux-foundation.org, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com, arnd@arndb.de From: Dave Hansen Message-ID: Date: Fri, 16 Mar 2018 15:19:12 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1519264541-7621-12-git-send-email-linuxram@us.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kselftest-owner@vger.kernel.org X-Mailing-List: linux-kselftest@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1593064626705149797?= X-GMAIL-MSGID: =?utf-8?q?1595134487150749111?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 02/21/2018 05:55 PM, Ram Pai wrote: > expected_pkey_fault() is comparing the contents of pkey > register with 0. This may not be true all the time. There > could be bits set by default by the architecture > which can never be changed. Hence compare the value against > shadow pkey register, which is supposed to track the bits > accurately all throughout > > cc: Dave Hansen > cc: Florian Weimer > Signed-off-by: Ram Pai > --- > tools/testing/selftests/vm/protection_keys.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c > index 254b66d..6054093 100644 > --- a/tools/testing/selftests/vm/protection_keys.c > +++ b/tools/testing/selftests/vm/protection_keys.c > @@ -926,10 +926,10 @@ void expected_pkey_fault(int pkey) > pkey_assert(last_pkey_faults + 1 == pkey_faults); > pkey_assert(last_si_pkey == pkey); > /* > - * The signal handler shold have cleared out PKEY register to let the > + * The signal handler shold have cleared out pkey-register to let the Heh, you randomly changed the formatting and didn't bother with my awful typo. :) > * test program continue. We now have to restore it. > */ > - if (__rdpkey_reg() != 0) > + if (__rdpkey_reg() != shadow_pkey_reg) > pkey_assert(0); > > __wrpkey_reg(shadow_pkey_reg); > I don't think this should be "shadow_pkey_reg". This was just trying to double-check that the signal handler messed around with PKRU the way we expected. We could also just check that the disable bits for 'pkey' are clear at this point. That would be almost as good.