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=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 16DBAC433DF for ; Wed, 29 Jul 2020 12:34:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E169E2083B for ; Wed, 29 Jul 2020 12:34:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZT70JLS/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726878AbgG2Meh (ORCPT ); Wed, 29 Jul 2020 08:34:37 -0400 Received: from us-smtp-delivery-74.mimecast.com ([216.205.24.74]:56556 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726853AbgG2Meg (ORCPT ); Wed, 29 Jul 2020 08:34:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1596026074; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=vpjuFUWMrn9WdHgMkjvTUGEbQN0jEb4t1IAuJiFnXjk=; b=ZT70JLS/OQTYWiIEJrreNRO3hnxb2H2hvAtupLp0NvsMpIqwHO2ixRfk1CAJ8mtSGDaxrY aXKl+nHmy9IVfVFGCsl3mYhn+nlJCX7yefPz5PIzjf7XKTUH9X4YSubJnWme0qLLnyvBMc ufbZNGGekvLLWEyGzsWCAS5ILzg0X/M= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-141-h_FhbikHPpedD8tYSaoKKg-1; Wed, 29 Jul 2020 08:34:30 -0400 X-MC-Unique: h_FhbikHPpedD8tYSaoKKg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CFF6D193F561; Wed, 29 Jul 2020 12:34:28 +0000 (UTC) Received: from [10.10.115.176] (ovpn-115-176.rdu2.redhat.com [10.10.115.176]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D484271917; Wed, 29 Jul 2020 12:34:04 +0000 (UTC) Subject: Re: WARNING: suspicious RCU usage - while installing a VM on a CPU listed under nohz_full To: Wanpeng Li Cc: LKML , KVM list , Wanpeng Li , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Liran Alon , "frederic@kernel.org" , Thomas Gleixner , Juri Lelli References: From: Nitesh Narayan Lal Autocrypt: addr=nitesh@redhat.com; prefer-encrypt=mutual; keydata= mQINBFl4pQoBEADT/nXR2JOfsCjDgYmE2qonSGjkM1g8S6p9UWD+bf7YEAYYYzZsLtbilFTe z4nL4AV6VJmC7dBIlTi3Mj2eymD/2dkKP6UXlliWkq67feVg1KG+4UIp89lFW7v5Y8Muw3Fm uQbFvxyhN8n3tmhRe+ScWsndSBDxYOZgkbCSIfNPdZrHcnOLfA7xMJZeRCjqUpwhIjxQdFA7 n0s0KZ2cHIsemtBM8b2WXSQG9CjqAJHVkDhrBWKThDRF7k80oiJdEQlTEiVhaEDURXq+2XmG jpCnvRQDb28EJSsQlNEAzwzHMeplddfB0vCg9fRk/kOBMDBtGsTvNT9OYUZD+7jaf0gvBvBB lbKmmMMX7uJB+ejY7bnw6ePNrVPErWyfHzR5WYrIFUtgoR3LigKnw5apzc7UIV9G8uiIcZEn C+QJCK43jgnkPcSmwVPztcrkbC84g1K5v2Dxh9amXKLBA1/i+CAY8JWMTepsFohIFMXNLj+B RJoOcR4HGYXZ6CAJa3Glu3mCmYqHTOKwezJTAvmsCLd3W7WxOGF8BbBjVaPjcZfavOvkin0u DaFvhAmrzN6lL0msY17JCZo046z8oAqkyvEflFbC0S1R/POzehKrzQ1RFRD3/YzzlhmIowkM BpTqNBeHEzQAlIhQuyu1ugmQtfsYYq6FPmWMRfFPes/4JUU/PQARAQABtCVOaXRlc2ggTmFy YXlhbiBMYWwgPG5pbGFsQHJlZGhhdC5jb20+iQI9BBMBCAAnBQJZeKUKAhsjBQkJZgGABQsJ CAcCBhUICQoLAgQWAgMBAh4BAheAAAoJEKOGQNwGMqM56lEP/A2KMs/pu0URcVk/kqVwcBhU SnvB8DP3lDWDnmVrAkFEOnPX7GTbactQ41wF/xwjwmEmTzLrMRZpkqz2y9mV0hWHjqoXbOCS 6RwK3ri5e2ThIPoGxFLt6TrMHgCRwm8YuOSJ97o+uohCTN8pmQ86KMUrDNwMqRkeTRW9wWIQ EdDqW44VwelnyPwcmWHBNNb1Kd8j3xKlHtnS45vc6WuoKxYRBTQOwI/5uFpDZtZ1a5kq9Ak/ MOPDDZpd84rqd+IvgMw5z4a5QlkvOTpScD21G3gjmtTEtyfahltyDK/5i8IaQC3YiXJCrqxE r7/4JMZeOYiKpE9iZMtS90t4wBgbVTqAGH1nE/ifZVAUcCtycD0f3egX9CHe45Ad4fsF3edQ ESa5tZAogiA4Hc/yQpnnf43a3aQ67XPOJXxS0Qptzu4vfF9h7kTKYWSrVesOU3QKYbjEAf95 NewF9FhAlYqYrwIwnuAZ8TdXVDYt7Z3z506//sf6zoRwYIDA8RDqFGRuPMXUsoUnf/KKPrtR ceLcSUP/JCNiYbf1/QtW8S6Ca/4qJFXQHp0knqJPGmwuFHsarSdpvZQ9qpxD3FnuPyo64S2N Dfq8TAeifNp2pAmPY2PAHQ3nOmKgMG8Gn5QiORvMUGzSz8Lo31LW58NdBKbh6bci5+t/HE0H pnyVf5xhNC/FuQINBFl4pQoBEACr+MgxWHUP76oNNYjRiNDhaIVtnPRqxiZ9v4H5FPxJy9UD Bqr54rifr1E+K+yYNPt/Po43vVL2cAyfyI/LVLlhiY4yH6T1n+Di/hSkkviCaf13gczuvgz4 KVYLwojU8+naJUsiCJw01MjO3pg9GQ+47HgsnRjCdNmmHiUQqksMIfd8k3reO9SUNlEmDDNB XuSzkHjE5y/R/6p8uXaVpiKPfHoULjNRWaFc3d2JGmxJpBdpYnajoz61m7XJlgwl/B5Ql/6B dHGaX3VHxOZsfRfugwYF9CkrPbyO5PK7yJ5vaiWre7aQ9bmCtXAomvF1q3/qRwZp77k6i9R3 tWfXjZDOQokw0u6d6DYJ0Vkfcwheg2i/Mf/epQl7Pf846G3PgSnyVK6cRwerBl5a68w7xqVU 4KgAh0DePjtDcbcXsKRT9D63cfyfrNE+ea4i0SVik6+N4nAj1HbzWHTk2KIxTsJXypibOKFX 2VykltxutR1sUfZBYMkfU4PogE7NjVEU7KtuCOSAkYzIWrZNEQrxYkxHLJsWruhSYNRsqVBy KvY6JAsq/i5yhVd5JKKU8wIOgSwC9P6mXYRgwPyfg15GZpnw+Fpey4bCDkT5fMOaCcS+vSU1 UaFmC4Ogzpe2BW2DOaPU5Ik99zUFNn6cRmOOXArrryjFlLT5oSOe4IposgWzdwARAQABiQIl BBgBCAAPBQJZeKUKAhsMBQkJZgGAAAoJEKOGQNwGMqM5ELoP/jj9d9gF1Al4+9bngUlYohYu 0sxyZo9IZ7Yb7cHuJzOMqfgoP4tydP4QCuyd9Q2OHHL5AL4VFNb8SvqAxxYSPuDJTI3JZwI7 d8JTPKwpulMSUaJE8ZH9n8A/+sdC3CAD4QafVBcCcbFe1jifHmQRdDrvHV9Es14QVAOTZhnJ vweENyHEIxkpLsyUUDuVypIo6y/Cws+EBCWt27BJi9GH/EOTB0wb+2ghCs/i3h8a+bi+bS7L FCCm/AxIqxRurh2UySn0P/2+2eZvneJ1/uTgfxnjeSlwQJ1BWzMAdAHQO1/lnbyZgEZEtUZJ x9d9ASekTtJjBMKJXAw7GbB2dAA/QmbA+Q+Xuamzm/1imigz6L6sOt2n/X/SSc33w8RJUyor SvAIoG/zU2Y76pKTgbpQqMDmkmNYFMLcAukpvC4ki3Sf086TdMgkjqtnpTkEElMSFJC8npXv 3QnGGOIfFug/qs8z03DLPBz9VYS26jiiN7QIJVpeeEdN/LKnaz5LO+h5kNAyj44qdF2T2AiF HxnZnxO5JNP5uISQH3FjxxGxJkdJ8jKzZV7aT37sC+Rp0o3KNc+GXTR+GSVq87Xfuhx0LRST NK9ZhT0+qkiN7npFLtNtbzwqaqceq3XhafmCiw8xrtzCnlB/C4SiBr/93Ip4kihXJ0EuHSLn VujM7c/b4pps Organization: Red Hat Inc, Message-ID: <57ea501b-bf54-3fc0-4a8f-2820df623b14@redhat.com> Date: Wed, 29 Jul 2020 08:34:02 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="uP5kPhxszyverNECWhXQL2pWCXsNZwIT3" Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --uP5kPhxszyverNECWhXQL2pWCXsNZwIT3 Content-Type: multipart/mixed; boundary="aewA7KPMFFsjEBrrWzBF8yJT1ydYVsyUm" --aewA7KPMFFsjEBrrWzBF8yJT1ydYVsyUm Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Language: en-US On 7/28/20 10:38 PM, Wanpeng Li wrote: > Hi Nitesh=EF=BC=8C > On Wed, 29 Jul 2020 at 09:00, Wanpeng Li wrote: >> On Tue, 28 Jul 2020 at 22:40, Nitesh Narayan Lal wro= te: >>> Hi, >>> >>> I have recently come across an RCU trace with the 5.8-rc7 kernel that h= as the >>> debug configs enabled while installing a VM on a CPU that is listed und= er >>> nohz_full. >>> >>> Based on some of the initial debugging, my impression is that the issue= is >>> triggered because of the fastpath that is meant to optimize the writes = to x2APIC >>> ICR that eventually leads to a virtual IPI in fixed delivery mode, is g= etting >>> invoked from the quiescent state. > Could you try latest linux-next tree? I guess maybe some patches are > pending in linux-next tree, I can't reproduce against linux-next tree. Sure, I will try this today. > --=20 Nitesh --aewA7KPMFFsjEBrrWzBF8yJT1ydYVsyUm-- --uP5kPhxszyverNECWhXQL2pWCXsNZwIT3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEkXcoRVGaqvbHPuAGo4ZA3AYyozkFAl8hbLoACgkQo4ZA3AYy ozlZvg/+LT3pvapMn9VLl3twNaZIEHWtQw30VDPKArk34leSbQp03otfi+5eevwB z8nRH7eRSRX6C1E2b5CQfGArHJOSnIG0rDMoSssjdZ/j1IlgDCkz2opSWRnXmMZW T4gRo9Yrx/iJ1c/dkGgYPua/mThq4HaayCK/oYyce+7XUhZqbiFOyEi4GtmEv3J9 Pog/da4dPJOJ8X7fSJ3QANiMB1cTTReCKEbLo2tKn5YOLvU/kParAMVLN0di4J0q pZQF3THHMFa8pmRbfs1Ew6ntPRAy8w84pRGjc4YkVwZVphQyEfbWShl28avXCEpw 7zeVNZGc0QOJONWyajlJH3sWdiYJucAWHWnCCcP4JP9Eu8Q1ELbUuoTLAXZW0m3e L+Kgr/Wk03QilVLI7ubHQ4jNA2Lzor97jgCv/WMSs+BtvMQb4EycmaLhfXkSdemo rvedo4ALiBUUTrECeiKWVrWTf0Ov7vy8nklAdGqQpb2wLk7e3AQ1U1XbqPd49E0v 0Eln8yHmIJL6PT3DmAM5aaW4ucB/TllqD8lvam//ToZsw0BZjPl5Z+j1nqk1uavf gqwwDRK5DI1vZBcpkA005O7aiRrrSRhjHX1vWbJZbNpIm5vmbACVh2h2gyTTfqLP ylW6auqQeGGScnVzsf9As1+ERR1oF/Op0Iz1ii5ZX8kq7W0PLyM= =/NZJ -----END PGP SIGNATURE----- --uP5kPhxszyverNECWhXQL2pWCXsNZwIT3--