From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sean Christopherson Date: Fri, 07 Feb 2020 18:07:20 +0000 Subject: Re: [PATCH v5 12/19] KVM: Move memslot deletion to helper function Message-Id: <20200207180720.GH2401@linux.intel.com> List-Id: References: <20200121223157.15263-1-sean.j.christopherson@intel.com> <20200121223157.15263-13-sean.j.christopherson@intel.com> <20200206161415.GA695333@xz-x1> <20200206162818.GD13067@linux.intel.com> <20200206165116.GE695333@xz-x1> <20200207175912.GG2401@linux.intel.com> In-Reply-To: <20200207175912.GG2401@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Peter Xu Cc: Paolo Bonzini , Paul Mackerras , Christian Borntraeger , Janosch Frank , David Hildenbrand , Cornelia Huck , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, Christoffer Dall , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= On Fri, Feb 07, 2020 at 09:59:12AM -0800, Sean Christopherson wrote: > On Thu, Feb 06, 2020 at 11:51:16AM -0500, Peter Xu wrote: > > /* > > * Make a full copy of the old memslot, the pointer will become stale > > * when the memslots are re-sorted by update_memslots() in > > * kvm_delete_memslot(), while to make the kvm_free_memslot() work as > > * expected later on, we still need the cached memory slot. > > */ > > As above, it's more subtle than just the kvm_delete_memslot() case. > > /* > * Make a full copy of the old memslot, the pointer will become stale > * when the memslots are re-sorted by update_memslots() when deleting > * or moving a memslot, and additional modifications to the old memslot > * need to be made after calling update_memslots(). > */ Actually, that's not quite correct, as the same is true for all memslot updates, and we still query @old after update_memslots() for CREATE and FLAGS. This is better. /* * Make a full copy of the old memslot, the pointer will become stale * when the memslots are re-sorted by update_memslots(), and the old * memslot needs to be referenced after calling update_memslots(), e.g. * to free its resources and for arch specific behavior. */ 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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 57930C2BA83 for ; Fri, 7 Feb 2020 18:07:27 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id DD1E420726 for ; Fri, 7 Feb 2020 18:07:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DD1E420726 Authentication-Results: mail.kernel.org; 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Fri, 7 Feb 2020 13:07:23 -0500 (EST) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 0D8D74A3A5 for ; Fri, 7 Feb 2020 13:07:22 -0500 (EST) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Feb 2020 10:07:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,414,1574150400"; d="scan'208";a="432641480" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by fmsmga006.fm.intel.com with ESMTP; 07 Feb 2020 10:07:20 -0800 Date: Fri, 7 Feb 2020 10:07:20 -0800 From: Sean Christopherson To: Peter Xu Subject: Re: [PATCH v5 12/19] KVM: Move memslot deletion to helper function Message-ID: <20200207180720.GH2401@linux.intel.com> References: <20200121223157.15263-1-sean.j.christopherson@intel.com> <20200121223157.15263-13-sean.j.christopherson@intel.com> <20200206161415.GA695333@xz-x1> <20200206162818.GD13067@linux.intel.com> <20200206165116.GE695333@xz-x1> <20200207175912.GG2401@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200207175912.GG2401@linux.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Cc: Wanpeng Li , kvm@vger.kernel.org, David Hildenbrand , linux-mips@vger.kernel.org, Paul Mackerras , kvmarm@lists.cs.columbia.edu, Janosch Frank , Marc Zyngier , Joerg Roedel , Christian Borntraeger , kvm-ppc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Jim Mattson , Cornelia Huck , linux-kernel@vger.kernel.org, Paolo Bonzini , Vitaly Kuznetsov , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On Fri, Feb 07, 2020 at 09:59:12AM -0800, Sean Christopherson wrote: > On Thu, Feb 06, 2020 at 11:51:16AM -0500, Peter Xu wrote: > > /* > > * Make a full copy of the old memslot, the pointer will become stale > > * when the memslots are re-sorted by update_memslots() in > > * kvm_delete_memslot(), while to make the kvm_free_memslot() work as > > * expected later on, we still need the cached memory slot. > > */ > > As above, it's more subtle than just the kvm_delete_memslot() case. > > /* > * Make a full copy of the old memslot, the pointer will become stale > * when the memslots are re-sorted by update_memslots() when deleting > * or moving a memslot, and additional modifications to the old memslot > * need to be made after calling update_memslots(). > */ Actually, that's not quite correct, as the same is true for all memslot updates, and we still query @old after update_memslots() for CREATE and FLAGS. This is better. /* * Make a full copy of the old memslot, the pointer will become stale * when the memslots are re-sorted by update_memslots(), and the old * memslot needs to be referenced after calling update_memslots(), e.g. * to free its resources and for arch specific behavior. */ _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 34907C2BA83 for ; Fri, 7 Feb 2020 18:07:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 152A220726 for ; Fri, 7 Feb 2020 18:07:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726956AbgBGSHV (ORCPT ); Fri, 7 Feb 2020 13:07:21 -0500 Received: from mga14.intel.com ([192.55.52.115]:38121 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726900AbgBGSHV (ORCPT ); Fri, 7 Feb 2020 13:07:21 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Feb 2020 10:07:20 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,414,1574150400"; d="scan'208";a="432641480" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by fmsmga006.fm.intel.com with ESMTP; 07 Feb 2020 10:07:20 -0800 Date: Fri, 7 Feb 2020 10:07:20 -0800 From: Sean Christopherson To: Peter Xu Cc: Paolo Bonzini , Paul Mackerras , Christian Borntraeger , Janosch Frank , David Hildenbrand , Cornelia Huck , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, Christoffer Dall , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Subject: Re: [PATCH v5 12/19] KVM: Move memslot deletion to helper function Message-ID: <20200207180720.GH2401@linux.intel.com> References: <20200121223157.15263-1-sean.j.christopherson@intel.com> <20200121223157.15263-13-sean.j.christopherson@intel.com> <20200206161415.GA695333@xz-x1> <20200206162818.GD13067@linux.intel.com> <20200206165116.GE695333@xz-x1> <20200207175912.GG2401@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200207175912.GG2401@linux.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Fri, Feb 07, 2020 at 09:59:12AM -0800, Sean Christopherson wrote: > On Thu, Feb 06, 2020 at 11:51:16AM -0500, Peter Xu wrote: > > /* > > * Make a full copy of the old memslot, the pointer will become stale > > * when the memslots are re-sorted by update_memslots() in > > * kvm_delete_memslot(), while to make the kvm_free_memslot() work as > > * expected later on, we still need the cached memory slot. > > */ > > As above, it's more subtle than just the kvm_delete_memslot() case. > > /* > * Make a full copy of the old memslot, the pointer will become stale > * when the memslots are re-sorted by update_memslots() when deleting > * or moving a memslot, and additional modifications to the old memslot > * need to be made after calling update_memslots(). > */ Actually, that's not quite correct, as the same is true for all memslot updates, and we still query @old after update_memslots() for CREATE and FLAGS. This is better. /* * Make a full copy of the old memslot, the pointer will become stale * when the memslots are re-sorted by update_memslots(), and the old * memslot needs to be referenced after calling update_memslots(), e.g. * to free its resources and for arch specific behavior. */ 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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 D5D31C2BA83 for ; Fri, 7 Feb 2020 18:07:35 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AC7E620726 for ; Fri, 7 Feb 2020 18:07:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="bKGQP7o+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AC7E620726 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=SUMR7y+Pbiaft+qnlPDgKvfUXam2NlAWGCGf+z/P/+g=; b=bKGQP7o+2qT0XN iHcvf2wKEK+eJvzM4OEL8O1tnbIGy/dAVGV7vz5foaXUz9MU4QzHX/uyMeOrrUkm4x4ofqI7sLxcS j07PbemZTFacB54apm0w66w2ufq/GI4+NWaS9qVlpn+gYaBIeakxrVl6+aAacN+A8uilymHrtTByf 2oZPq4HUL/ujR2Nr54b+jWOT/UyRPrait2zvbnhiyp7TR+e1Gp+4aNFDPMBAMCXs17HPTKkpypnh3 xirdhHfL0bvYTFzHFoYY1gj5zcUeASQu7RIKEAH8GaT4CmmzN0Ri4qfIyzwZtPeRXCeY5KaS6zK/X cIwbxQG1bSaWpLlhCoYA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j082M-0006Z0-Rj; Fri, 07 Feb 2020 18:07:30 +0000 Received: from mga02.intel.com ([134.134.136.20]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j082K-0006Ya-OJ for linux-arm-kernel@lists.infradead.org; Fri, 07 Feb 2020 18:07:30 +0000 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Feb 2020 10:07:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,414,1574150400"; d="scan'208";a="432641480" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by fmsmga006.fm.intel.com with ESMTP; 07 Feb 2020 10:07:20 -0800 Date: Fri, 7 Feb 2020 10:07:20 -0800 From: Sean Christopherson To: Peter Xu Subject: Re: [PATCH v5 12/19] KVM: Move memslot deletion to helper function Message-ID: <20200207180720.GH2401@linux.intel.com> References: <20200121223157.15263-1-sean.j.christopherson@intel.com> <20200121223157.15263-13-sean.j.christopherson@intel.com> <20200206161415.GA695333@xz-x1> <20200206162818.GD13067@linux.intel.com> <20200206165116.GE695333@xz-x1> <20200207175912.GG2401@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200207175912.GG2401@linux.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200207_100728_879076_3ADE350C X-CRM114-Status: GOOD ( 10.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Wanpeng Li , kvm@vger.kernel.org, David Hildenbrand , linux-mips@vger.kernel.org, Paul Mackerras , kvmarm@lists.cs.columbia.edu, Janosch Frank , Marc Zyngier , Joerg Roedel , Christian Borntraeger , Julien Thierry , Suzuki K Poulose , kvm-ppc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Jim Mattson , Cornelia Huck , Christoffer Dall , linux-kernel@vger.kernel.org, James Morse , Paolo Bonzini , Vitaly Kuznetsov , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Feb 07, 2020 at 09:59:12AM -0800, Sean Christopherson wrote: > On Thu, Feb 06, 2020 at 11:51:16AM -0500, Peter Xu wrote: > > /* > > * Make a full copy of the old memslot, the pointer will become stale > > * when the memslots are re-sorted by update_memslots() in > > * kvm_delete_memslot(), while to make the kvm_free_memslot() work as > > * expected later on, we still need the cached memory slot. > > */ > > As above, it's more subtle than just the kvm_delete_memslot() case. > > /* > * Make a full copy of the old memslot, the pointer will become stale > * when the memslots are re-sorted by update_memslots() when deleting > * or moving a memslot, and additional modifications to the old memslot > * need to be made after calling update_memslots(). > */ Actually, that's not quite correct, as the same is true for all memslot updates, and we still query @old after update_memslots() for CREATE and FLAGS. This is better. /* * Make a full copy of the old memslot, the pointer will become stale * when the memslots are re-sorted by update_memslots(), and the old * memslot needs to be referenced after calling update_memslots(), e.g. * to free its resources and for arch specific behavior. */ _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel