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=-4.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 75649C48BCF for ; Sun, 13 Jun 2021 12:44:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47F8F60FE6 for ; Sun, 13 Jun 2021 12:44:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231760AbhFMMqW (ORCPT ); Sun, 13 Jun 2021 08:46:22 -0400 Received: from forward105p.mail.yandex.net ([77.88.28.108]:53007 "EHLO forward105p.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231733AbhFMMqV (ORCPT ); Sun, 13 Jun 2021 08:46:21 -0400 X-Greylist: delayed 450 seconds by postgrey-1.27 at vger.kernel.org; Sun, 13 Jun 2021 08:46:21 EDT Received: from myt5-95f184467838.qloud-c.yandex.net (myt5-95f184467838.qloud-c.yandex.net [IPv6:2a02:6b8:c12:5981:0:640:95f1:8446]) by forward105p.mail.yandex.net (Yandex) with ESMTP id BCAC04D41219 for ; Sun, 13 Jun 2021 15:36:48 +0300 (MSK) Received: from myt6-efff10c3476a.qloud-c.yandex.net (myt6-efff10c3476a.qloud-c.yandex.net [2a02:6b8:c12:13a3:0:640:efff:10c3]) by myt5-95f184467838.qloud-c.yandex.net (mxback/Yandex) with ESMTP id KOGJbXhgh6-amI0bcQr; Sun, 13 Jun 2021 15:36:48 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1623587808; bh=40GLmJMHLXoOqUixsdtFsGY+AQQlYxAe2PcEAtt58NE=; h=In-Reply-To:Date:References:To:From:Subject:Message-ID; b=gRk5CAZcJdLJa/V4sc1He6rS54tRnKCAKSvSN7xzNIikrO+7EUMQVv6yKWGyrHwsh eWxnbRdBT8iwQMQ++0OibgZ7hRkLZt4EKwcXbXGYTAIEMgSckktdM2QRhJCpOLzr+3 WwGFMtxpJyn5/iDBhrRwXS7uW/IxQBa5C9UpQuu0= Authentication-Results: myt5-95f184467838.qloud-c.yandex.net; dkim=pass header.i=@yandex.ru Received: by myt6-efff10c3476a.qloud-c.yandex.net (smtp/Yandex) with ESMTPSA id hCj3MKLKEI-am2GrMS1; Sun, 13 Jun 2021 15:36:48 +0300 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client certificate not present) Subject: Re: guest/host mem out of sync on core2duo? From: stsp To: kvm@vger.kernel.org References: Message-ID: <87035d8e-ad35-5cbb-a547-ee7c353221d4@yandex.ru> Date: Sun, 13 Jun 2021 15:36:48 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org 13.06.2021 01:49, stsp пишет: > I've found that the one needs to > check KVM_CAP_SYNC_MMU to > safely write to the guest memory, > but it doesn't seem to be documented > well. In fact, I wonder if its description in the kernel doc is even correct: --- When the KVM_CAP_SYNC_MMU capability is available, changes in the backing of the memory region are automatically reflected into the guest. --- But, after looking into the patches that introduce that capability, I've got an impression that it is only needed if you mmap() something else to the guest-shared region.