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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 1BF8DC432C0 for ; Tue, 19 Nov 2019 11:36:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D65722067D for ; Tue, 19 Nov 2019 11:36:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="n3BQGwCJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727850AbfKSLg2 (ORCPT ); Tue, 19 Nov 2019 06:36:28 -0500 Received: from mail-ot1-f67.google.com ([209.85.210.67]:45561 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726351AbfKSLg2 (ORCPT ); Tue, 19 Nov 2019 06:36:28 -0500 Received: by mail-ot1-f67.google.com with SMTP id r24so17534271otk.12; Tue, 19 Nov 2019 03:36:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=O4bgGlnr9YGraqcGqRTVWqBe6uwtLwxkzJh4SzEwyFo=; b=n3BQGwCJfycuAMFvnZDcr3Hu3ukTzjDamexrrbqiaODw+rVgtGLjTiBrkTLbLXr0KV 02hdg8VUZMlaPMJrBouxnpN0dVeRNlEHMPrZ/OHqurwG5weCsFK5b5m9e4c9YzOZ7qxL bN8OK6UnhNljuWzW7COd3E0FoGk0V0e71CiTVtJxUFRuKcPuCbT7RRdeq9fp1Ib4/B3o ESZzMIQS7diJdAp2RfpLOSD1sZHZ7u9LXOVjZNTZIejYhrTu+n+aLBBoyqw5ITuJrG2n cF+1wL7tzqwg5jkwagS/VTIA100j2yEGKE4zFlVWCQKUoZfQpcg36LFoG/Tp0CPe2M52 xqig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=O4bgGlnr9YGraqcGqRTVWqBe6uwtLwxkzJh4SzEwyFo=; b=WXD/n8gmwfRdgK4xN05UmOLtcYRAn38VX1VFibb74RzA1yVVmEuhN72jFBcLC80eBH OLKHwrvI2rUkrz6MDKgdwxss7uQEDupPRJimBDeaIZwv7Mm5F4BuqhwwlCBJ/4IjWQTa Oa+n/W+LJYGLp9+Ef6SK3vRx1eErW/+I3gAfi0Lzke79/vGIVkUQ75Nl0owZ0m+wu6ah n86FpVESy8YMv3oHd71L69i2i7INMXiB6hY8N9EVShint0pUSmAXi2osbVE3Gk6P0u0u /t9bkiZ3WYFTP2dIQM+JOnQwpl065EmLnPKSGEBAbpRjYl8erZ+bEXtz66wkx0FxSxZk Ma6g== X-Gm-Message-State: APjAAAWB8KuctPycfzGuaLo7OFof+5a/MtjRDjF1TGzfVksrDTyhOKu8 GBdEQcE4gzHHhyUY+LXLYnHyqQyrAGMT4KbNU4I= X-Google-Smtp-Source: APXvYqyDpAorsfYdBpBR7EzrIYuwOiOE/+kKmQo8NuX1/d/ejR8FXEbCO3p7ECFkoT2VHLhSYf+JnIGOFaAWsURHIeA= X-Received: by 2002:a05:6830:4ae:: with SMTP id l14mr3403148otd.185.1574163387705; Tue, 19 Nov 2019 03:36:27 -0800 (PST) MIME-Version: 1.0 References: <20191111172012.28356-1-joao.m.martins@oracle.com> <20191111172012.28356-3-joao.m.martins@oracle.com> In-Reply-To: <20191111172012.28356-3-joao.m.martins@oracle.com> From: Wanpeng Li Date: Tue, 19 Nov 2019 19:36:19 +0800 Message-ID: Subject: Re: [PATCH v2 2/3] KVM: VMX: Do not change PID.NDST when loading a blocked vCPU To: Joao Martins Cc: kvm , LKML , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Liran Alon , Jag Raman Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 12 Nov 2019 at 01:23, Joao Martins wrote: > > While vCPU is blocked (in kvm_vcpu_block()), it may be preempted which > will cause vmx_vcpu_pi_put() to set PID.SN. If later the vCPU will be How can this happen? See the prepare_to_swait_exlusive() in kvm_vcpu_block(), the task will be set in TASK_INTERRUPTIBLE state, kvm_sched_out will set vcpu->preempted to true iff current->state == TASK_RUNNING. Wanpeng