From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EAD53C43381 for ; Thu, 14 Feb 2019 21:32:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B6B8921B24 for ; Thu, 14 Feb 2019 21:32:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440222AbfBNVcK (ORCPT ); Thu, 14 Feb 2019 16:32:10 -0500 Received: from mx0b-002e3701.pphosted.com ([148.163.143.35]:46044 "EHLO mx0b-002e3701.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392871AbfBNVcI (ORCPT ); Thu, 14 Feb 2019 16:32:08 -0500 Received: from pps.filterd (m0134425.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1ELQhpY005571; Thu, 14 Feb 2019 21:31:51 GMT Received: from g4t3426.houston.hpe.com (g4t3426.houston.hpe.com [15.241.140.75]) by mx0b-002e3701.pphosted.com with ESMTP id 2qnedr8uhj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 14 Feb 2019 21:31:51 +0000 Received: from g9t2301.houston.hpecorp.net (g9t2301.houston.hpecorp.net [16.220.97.129]) by g4t3426.houston.hpe.com (Postfix) with ESMTP id 9A8B070; Thu, 14 Feb 2019 21:31:50 +0000 (UTC) Received: from [16.214.130.214] (unknown [16.214.130.214]) by g9t2301.houston.hpecorp.net (Postfix) with ESMTP id 094314B; Thu, 14 Feb 2019 21:31:48 +0000 (UTC) Subject: Re: [Patch v3 0/4] Protect against concurrent calls into UV BIOS To: Dimitri Sivanich , Hedi Berriche Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel , Thomas Gleixner , Bhupesh Sharma , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , linux-efi@vger.kernel.org, x86@kernel.org, Russ Anderson , Steve Wahl , stable@vger.kernel.org References: <20190213193413.25560-1-hedi.berriche@hpe.com> <20190214212149.GB5073@hpe.com> From: Mike Travis Message-ID: <6d2c7655-a8f4-e2ef-1479-f43e707c6a86@hpe.com> Date: Thu, 14 Feb 2019 13:31:48 -0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190214212149.GB5073@hpe.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-14_10:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1902140141 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/14/2019 1:21 PM, Dimitri Sivanich wrote: > For the series: > > Reviewed-by: Dimitri Sivanich As well as I: Reviewed-by: Mike Travis > > On Wed, Feb 13, 2019 at 07:34:09PM +0000, Hedi Berriche wrote: >> - Changes since v2 >> Addressed comments from Ard Biesheuvel: >> * expose efi_runtime_lock to UV platform only instead of globally >> * remove unnecessary #ifdef CONFIG_EFI from bios_uv.c >> >> - Changes since v1: >> Addressed comments from Bhupesh Sharma, Thomas Gleixner, and Ard Biesheuvel: >> * made __uv_bios_call() static >> * moved the efi_enabled() cleanup to its own patchlet >> * explained the reason for renaming the efi_runtime_lock semaphore >> * dropped the reviewed-bys as they should be given on the mailing list >> * Cc'ng stable@vger.kernel.org given the nature of the problem addressed by the patches >> >> --- >> >> Calls into UV BIOS were not being serialised which is wrong as it violates EFI >> runtime rules, and bad as it does result in all sorts of potentially hard to >> track down hangs and panics when efi_scratch.prev_mm gets clobbered whenever >> efi_switch_mm() gets called concurrently from two different CPUs. >> >> Patch #1 removes an unnecessary #ifdef CONFIG_EFI guard from bios_uv.c. >> >> Patch #2 removes uv_bios_call_reentrant() because it's dead code. >> >> Patch #3 is a cleanup that drops test_bit() in favour of the ad hoc efi_enabled(). >> >> Patch #4 makes uv_bios_call() variants use the efi_runtime_lock semaphore to >> protect against concurrency. >> >> Cc: Russ Anderson >> Cc: Mike Travis >> Cc: Dimitri Sivanich >> Cc: Steve Wahl >> Cc: stable@vger.kernel.org # v4.9+ >> >> Hedi Berriche (4): >> x86/platform/UV: remove unnecessary #ifdef CONFIG_EFI >> x86/platform/UV: kill uv_bios_call_reentrant() as it has no callers >> x86/platform/UV: use efi_enabled() instead of test_bit() >> x86/platform/UV: use efi_runtime_lock to serialise BIOS calls >> >> arch/x86/include/asm/uv/bios.h | 13 ++++----- >> arch/x86/platform/uv/bios_uv.c | 35 ++++++++++++++----------- >> drivers/firmware/efi/runtime-wrappers.c | 7 +++++ >> 3 files changed, 34 insertions(+), 21 deletions(-) >> >> -- >> 2.20.1 >>