Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754507AbdDKJhb (ORCPT ); Tue, 11 Apr 2017 05:37:31 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:43142 "EHLO imgpgp01.kl.imgtec.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752832AbdDKJh3 (ORCPT ); Tue, 11 Apr 2017 05:37:29 -0400 X-PGP-Universal: processed; by imgpgp01.kl.imgtec.org on Tue, 11 Apr 2017 11:43:56 +0100 Date: Tue, 11 Apr 2017 10:37:26 +0100 From: James Hogan To: Paolo Bonzini CC: Radim =?utf-8?B?S3LEjW3DocWZ?= , , , Christoffer Dall , Andrew Jones , Marc Zyngier , Christian Borntraeger , Cornelia Huck , Paul Mackerras Subject: Re: [PATCH RFC 1/6] KVM: fix guest_mode optimization in kvm_make_all_cpus_request() Message-ID: <20170411093726.GA31606@jhogan-linux.le.imgtec.org> References: <20170406202056.18379-1-rkrcmar@redhat.com> <20170406202056.18379-2-rkrcmar@redhat.com> <20170406210215.GV31606@jhogan-linux.le.imgtec.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="8Y8a5CJOPM/zJV44" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Originating-IP: [192.168.154.110] X-ESG-ENCRYPT-TAG: 1b7d744b Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1890 Lines: 51 --8Y8a5CJOPM/zJV44 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Paolo, On Tue, Apr 11, 2017 at 01:25:04PM +0800, Paolo Bonzini wrote: > On 07/04/2017 05:02, James Hogan wrote: > > This presumably changes the behaviour on x86, from !=3D OUTSIDE_GUEST_M= ODE > > to =3D=3D IN_GUEST_MODE. so: > > - you'll no longer get IPIs if its in READING_SHADOW_PAGE_TABLES (which > > MIPS also now uses when accessing mappings outside of guest mode and > > depends upon to wait until the old mappings are no longer in use). >=20 > This is wrong, the purpose of READING_SHADOW_PAGE_TABLES is "kvm_flush_re= mote_tlbs > should send me an IPI, because I want to stop kvm_flush_remote_tlbs until= I'm done > reading the page tables". That sounds equivalent to what I meant for MIPS, i.e. kvm_flush_remote_tlbs() does the waiting (not the thing accessing guest mappings). Cheers James --8Y8a5CJOPM/zJV44 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iQIcBAEBCAAGBQJY7KPWAAoJEGwLaZPeOHZ6X60P/2K5y3/pR3KY97yYsAypMTIL rHubzz135xRAaz18Ztg6PTk/zci26NY4IilX4K1h8vUwAJLpuKPWjlqL+HCXBpVZ KnM0jUQY2TIOHKn5TIgmSC7zfvmRTX5jB82UhiboKM9ZITwNY5bdesg7vlXOZ1MQ Xq28SlFc2PGX84JPqvZuUfC0ZyBWtyExP5OpIbWZoOwmNEJnFqWo01lrHsOjv9kG miaif1G5lxN9VSALvOd0OqlTz5lBQbGyosqlfHIpTIWE9/G+TPP0lEzRpTOsBuWX WMMUlLSdMuGez2R1My1q1YAy2xDw1ZEdFsr5X7/90/Ye4ja1GfSBLWnB5rGZ02CM r2ytkyMe6hwyy9BaAl095iTu6w2kT1jHikrIJKnA465LrNlupqY2eAX3t79+EibR 9leJPronec/Y36V8L9+KDB+F9smq5g55D9FpIJtO9z5VaXTIZUjZCoFCcAEfo+Ts Lhqu5X+4k+Pb94B11fCqomed3hEj5eTKGnDdysVNhtye8ZuHJJhEeo/7lDLhS1h9 WeYg8G8dD5HPhc3P6gA3SeDefudawsiGiiZ+zPAvQMNp4Z/eGGXpWIclQtKNlTz7 T8OeWMCSKGXsrl5/INNaGUSMqM69Cz5VFwkBopnwqsylaAggQKhxAEJtnzRnn8f2 Bm9xkV8ELWuT26qxLG1R =NU61 -----END PGP SIGNATURE----- --8Y8a5CJOPM/zJV44--