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=-0.8 required=3.0 tests=FROM_EXCESS_BASE64, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 108D8C433FF for ; Wed, 14 Aug 2019 09:39:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B957120578 for ; Wed, 14 Aug 2019 09:39:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B957120578 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bitdefender.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4B3BB6B0005; Wed, 14 Aug 2019 05:39:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 464C56B0006; Wed, 14 Aug 2019 05:39:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 37B716B0007; Wed, 14 Aug 2019 05:39:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0180.hostedemail.com [216.40.44.180]) by kanga.kvack.org (Postfix) with ESMTP id 181EC6B0005 for ; Wed, 14 Aug 2019 05:39:07 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id AC76B8248AA2 for ; Wed, 14 Aug 2019 09:39:06 +0000 (UTC) X-FDA: 75820534692.16.dogs59_4f7ec34b7a131 X-HE-Tag: dogs59_4f7ec34b7a131 X-Filterd-Recvd-Size: 2999 Received: from mx01.bbu.dsd.mx.bitdefender.com (mx01.bbu.dsd.mx.bitdefender.com [91.199.104.161]) by imf35.hostedemail.com (Postfix) with ESMTP for ; Wed, 14 Aug 2019 09:39:06 +0000 (UTC) Received: from smtp.bitdefender.com (smtp02.buh.bitdefender.net [10.17.80.76]) by mx01.bbu.dsd.mx.bitdefender.com (Postfix) with ESMTPS id 46468305FFAD; Wed, 14 Aug 2019 12:39:04 +0300 (EEST) Received: from localhost (unknown [195.210.5.22]) by smtp.bitdefender.com (Postfix) with ESMTPSA id 2FAD9303EF05; Wed, 14 Aug 2019 12:39:04 +0300 (EEST) From: Adalbert =?iso-8859-2?b?TGF643I=?= Subject: Re: [RFC PATCH v6 14/92] kvm: introspection: handle introspection commands before returning to guest To: Paolo Bonzini , kvm@vger.kernel.org Cc: linux-mm@kvack.org, virtualization@lists.linux-foundation.org, Radim =?iso-8859-2?b?S3LobeH4?= , Konrad Rzeszutek Wilk , Tamas K Lengyel , Mathieu Tarral , Samuel =?iso-8859-1?q?Laur=E9n?= , Patrick Colp , Jan Kiszka , Stefan Hajnoczi , Weijiang Yang , Yu C Zhang , Mihai =?UTF-8?b?RG9uyJt1?= , Mircea =?iso-8859-1?q?C=EErjaliu?= In-Reply-To: <97cdf9cb-286c-2387-6cb5-003b30f74c7e@redhat.com> References: <20190809160047.8319-1-alazar@bitdefender.com> <20190809160047.8319-15-alazar@bitdefender.com> <645d86f5-67f6-f5d3-3fbb-5ee9898a7ef8@redhat.com> <5d52c10e.1c69fb81.26904.fd34SMTPIN_ADDED_BROKEN@mx.google.com> <97cdf9cb-286c-2387-6cb5-003b30f74c7e@redhat.com> Date: Wed, 14 Aug 2019 12:39:31 +0300 Message-ID: <1565775571.4fFd4.4026.@15f23d3a749365d981e968181cce585d2dcb3ffa> Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000026, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 13 Aug 2019 16:45:11 +0200, Paolo Bonzini w= rote: > On 13/08/19 15:54, Adalbert Laz=C4=83r wrote: > > Leaving kvm_vcpu_block() in order to handle a request such as 'pa= use', > > would cause the vCPU to enter the guest when resumed. Most of the > > time this does not appear to be an issue, but during early boot i= t > > can happen for a non-boot vCPU to start executing code from areas= that > > first needed to be set up by vCPU #0. > > =20 > > In a particular case, vCPU #1 executed code which resided in an a= rea > > not covered by a memslot, which caused an EPT violation that got > > turned in mmu_set_spte() into a MMIO request that required emulat= ion. > > Unfortunatelly, the emulator tripped, exited to userspace and the= VM > > was aborted. >=20 > Okay, this makes sense. Maybe you want to handle KVM_REQ_INTROSPECTION > in vcpu_run rather than vcpu_enter_guest? >=20 > Paolo Right! We've missed that.