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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 65A4AC43387 for ; Mon, 17 Dec 2018 19:38:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3EDE6206A2 for ; Mon, 17 Dec 2018 19:38:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726710AbeLQTiG (ORCPT ); Mon, 17 Dec 2018 14:38:06 -0500 Received: from mga04.intel.com ([192.55.52.120]:21708 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726598AbeLQTiG (ORCPT ); Mon, 17 Dec 2018 14:38:06 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Dec 2018 11:38:05 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,366,1539673200"; d="scan'208";a="304566235" Received: from quwen-mobl.ccr.corp.intel.com (HELO localhost) ([10.249.254.215]) by fmsmga005.fm.intel.com with ESMTP; 17 Dec 2018 11:37:59 -0800 Date: Mon, 17 Dec 2018 21:37:58 +0200 From: Jarkko Sakkinen To: Dave Hansen Cc: Sean Christopherson , x86@kernel.org, platform-driver-x86@vger.kernel.org, linux-sgx@vger.kernel.org, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@linux.intel.com, andriy.shevchenko@linux.intel.com, tglx@linutronix.de, kai.svahn@intel.com, mark.shanahan@intel.com, luto@amacapital.net, Suresh Siddha , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Darren Hart , Andy Shevchenko , "open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" Subject: Re: [PATCH v17 18/23] platform/x86: Intel SGX driver Message-ID: <20181217193758.GC29785@linux.intel.com> References: <20181116010412.23967-1-jarkko.sakkinen@linux.intel.com> <20181116010412.23967-19-jarkko.sakkinen@linux.intel.com> <7d5cde02-4649-546b-0f03-2d6414bb80b5@intel.com> <20181217180102.GA12560@linux.intel.com> <20181217183613.GD12491@linux.intel.com> <20181217184333.GA26920@linux.intel.com> <20181217184858.GF12491@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Mon, Dec 17, 2018 at 11:09:33AM -0800, Dave Hansen wrote: > On 12/17/18 10:48 AM, Sean Christopherson wrote: > > We can't set mm to NULL as we need it to unregister the notifier, and > > I'm fairly certain attempting to unregister in the release callback > > will deadlock. > > Suggestion: > > It looks like you only expect one VMA per enclave. Things go bonkers if > this is not true. So, instead of storing encl->mm, don't. You can get > the mm from vma->vm_mm and you could just store encl->vma instead. The code actually supports having multiple VMAs per enclave. /Jarkko