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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 3485AC433DB for ; Tue, 26 Jan 2021 01:32:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB24323102 for ; Tue, 26 Jan 2021 01:32:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725900AbhAZBbk (ORCPT ); Mon, 25 Jan 2021 20:31:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731933AbhAZB3Q (ORCPT ); Mon, 25 Jan 2021 20:29:16 -0500 Received: from mail-oo1-xc32.google.com (mail-oo1-xc32.google.com [IPv6:2607:f8b0:4864:20::c32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04B56C0698D1; Mon, 25 Jan 2021 17:28:30 -0800 (PST) Received: by mail-oo1-xc32.google.com with SMTP id x23so3767383oop.1; Mon, 25 Jan 2021 17:28:29 -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:content-transfer-encoding; bh=6paGRqZC+Saiy/OdOWQy9bDY2PXfN0YJkrt0vyVzmXI=; b=K8X6g49rPyw3kREv1Dn/1hTN6EaW4ZmiqeMy6udTvVa98GSl/D5Bt0XdI/lgNGTfFa hBLDiUayFfthZAQPdRjdsWL+GoF/k5MJ4XrtkG4r3ETy7E2HWwLt0z7SJvKdJVcmwQtW ON3dN+WZbnpPGuztW44h97cX/Y/HwPQdtHBphjc3ODW57/GDuFFAicTKS2xybAeTKiuv GrX0gUnTYE+YDAdlC+CpyHbKNbs/bbF6MBbI9DKNGZ0jKc0dmhxHT7D3E/hGHlgVgO4X Etz5ERO6XeksR1k22n3uFvC0EFQjqof1V/RO/Qr4UsgAlKJVvdb4/3UjYAOlXmKIK0fy o6WQ== 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:content-transfer-encoding; bh=6paGRqZC+Saiy/OdOWQy9bDY2PXfN0YJkrt0vyVzmXI=; b=dElTSJZLxxmBk+DLdv009Ke92hEFCnjV/yz1zNmruggDzQ+6h79RS+bLPmxLchWWXX 5zesqR8olUYCeFm0QOEdVOJ/6OU/BW8vu3JHERUBLgz0lVY1gy+yjdNjA8cXrwC26iwl ZNu+3Zkd5TbdvVh6A8hbpDfxpoYOtJap06tiqDIm3RK4SiWfuf4T6co6LwQufbnC3Igu ihZQw4HOsE9qwxqrF68onLRQPLQnlRkwzaa3npnq/DkBJ9cxyXoCr0lbPERtzJRs90Qv vMckJXitwBJfnKJJC753dX1BZ3gw9JJ/oAd10FRw72FrlxMpHVYSM+MW6Pk1KNFua6kb /PvA== X-Gm-Message-State: AOAM530/L2mprmz2+owQIHdAXQIk0Uuf/2sAk+ggPKpGiK/qX4fmZPA7 mX/SC5+VtPOac8vPbsYzIaiwh4s9nMpEG/AEq7sJr+tDKD8= X-Google-Smtp-Source: ABdhPJzmkLV3iU8HhDDGcz85czAKO3NR4Cy9fFZK4aEWZplK3Mt2PZiGDbjZepscdMttmj0AiCMkoNL/st7iuznOHdE= X-Received: by 2002:a4a:946d:: with SMTP id j42mr2261363ooi.39.1611624509049; Mon, 25 Jan 2021 17:28:29 -0800 (PST) MIME-Version: 1.0 References: <1610960877-3110-1-git-send-email-wanpengli@tencent.com> In-Reply-To: <1610960877-3110-1-git-send-email-wanpengli@tencent.com> From: Wanpeng Li Date: Tue, 26 Jan 2021 09:28:17 +0800 Message-ID: Subject: Re: [PATCH v2] KVM: kvmclock: Fix vCPUs > 64 can't be online/hotpluged To: LKML , kvm Cc: Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Brijesh Singh Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org ping=EF=BC=8C On Mon, 18 Jan 2021 at 17:08, Wanpeng Li wrote: > > From: Wanpeng Li > > The per-cpu vsyscall pvclock data pointer assigns either an element of th= e > static array hv_clock_boot (#vCPU <=3D 64) or dynamically allocated memor= y > hvclock_mem (vCPU > 64), the dynamically memory will not be allocated if > kvmclock vsyscall is disabled, this can result in cpu hotpluged fails in > kvmclock_setup_percpu() which returns -ENOMEM. This patch fixes it by not > assigning vsyscall pvclock data pointer if kvmclock vdso_clock_mode is no= t > VDSO_CLOCKMODE_PVCLOCK. > > Fixes: 6a1cac56f4 ("x86/kvm: Use __bss_decrypted attribute in shared vari= ables") > Reported-by: Zelin Deng > Tested-by: Haiwei Li > Cc: Brijesh Singh > Cc: stable@vger.kernel.org#v4.19-rc5+ > Signed-off-by: Wanpeng Li > --- > v1 -> v2: > * add code comments > > arch/x86/kernel/kvmclock.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c > index aa59374..01d4e55c 100644 > --- a/arch/x86/kernel/kvmclock.c > +++ b/arch/x86/kernel/kvmclock.c > @@ -294,9 +294,11 @@ static int kvmclock_setup_percpu(unsigned int cpu) > /* > * The per cpu area setup replicates CPU0 data to all cpu > * pointers. So carefully check. CPU0 has been set up in init > - * already. > + * already. Assign vsyscall pvclock data pointer iff kvmclock > + * vsyscall is enabled. > */ > - if (!cpu || (p && p !=3D per_cpu(hv_clock_per_cpu, 0))) > + if (!cpu || (p && p !=3D per_cpu(hv_clock_per_cpu, 0)) || > + (kvm_clock.vdso_clock_mode !=3D VDSO_CLOCKMODE_PVCLOCK)) > return 0; > > /* Use the static page for the first CPUs, allocate otherwise */ > -- > 2.7.4 >