From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Ostrovsky Subject: Re: Is: EPT violations. Was:Re: Problems with pci/vga passthrough Date: Tue, 24 Jan 2017 16:43:55 -0500 Message-ID: References: <3650332.PVtMSBxIKa@bagend> <58878ABA020000780013373E@prv-mh.provo.novell.com> <55013379.QGovEA7yDG@bagend> <8e2d0c86-2274-8d9d-9a87-36177fd009cd@oracle.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1419496806262860922==" Return-path: In-Reply-To: <8e2d0c86-2274-8d9d-9a87-36177fd009cd@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" To: Diederik de Haas , xen-devel@lists.xen.org Cc: 852324@bugs.debian.org, Jan Beulich List-Id: xen-devel@lists.xenproject.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --===============1419496806262860922== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="fbjN4vJNsC4kA1ka6lejE9lFHF08dkpgu" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --fbjN4vJNsC4kA1ka6lejE9lFHF08dkpgu Content-Type: multipart/mixed; boundary="ssMkJKx553I29pdFKF0oMP1rtNRG1rurf"; protected-headers="v1" From: Boris Ostrovsky To: Diederik de Haas , xen-devel@lists.xen.org Cc: Jan Beulich , 852324@bugs.debian.org Message-ID: Subject: Re: [Xen-devel] Is: EPT violations. Was:Re: Problems with pci/vga passthrough References: <3650332.PVtMSBxIKa@bagend> <58878ABA020000780013373E@prv-mh.provo.novell.com> <55013379.QGovEA7yDG@bagend> <8e2d0c86-2274-8d9d-9a87-36177fd009cd@oracle.com> In-Reply-To: <8e2d0c86-2274-8d9d-9a87-36177fd009cd@oracle.com> --ssMkJKx553I29pdFKF0oMP1rtNRG1rurf Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable On 01/24/2017 01:51 PM, Boris Ostrovsky wrote: > On 01/24/2017 01:44 PM, Diederik de Haas wrote: >> On dinsdag 24 januari 2017 13:28:28 CET Boris Ostrovsky wrote: >>>>> Reported it at https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=3D= 852324 >>>>> but given Ben Hutchings' reaction it seems to be a Xen problem aft= er >>>>> all. >>>>> >>>>> Relevant part of earlier attached dmesg: >>>>> >>>>> [ 13.588386] WARNING: CPU: 18 PID: 1 at=20 >>>>> /build/linux-zDY19G/linux-4.8.15/arch/x86/mm/dump_pagetables.c:225 >>>>> note_page+0x5e8/0x790 [ 13.588388] x86/mm: Found insecure W+X map= ping >>>>> at address ffff880000000000/0xffff880000000000 ... >>>>> [ 13.608867] x86/mm: Checked W+X mappings: FAILED, 4602 W+X pages= >>>>> found. >>>> Now this is a know issue, but I'm pretty convinced one that's entire= ly >>>> unrelated to your problem. >>> I thought we fixed this. That's what is_hypervisor_range() was >>> introduced for, and I haven't seen this warning since then. Actually, I do see the warnings (I usually don't set CONFIG_DEBUG_WX). They are not for the hypervisor range though, so the commit below is not relevant. Nevertheless, as Jan said, it's unlikely to cause your problem. -boris >> When? Which commit? >> Maybe it isn't (yet) in the Debian tree and/or I am using a kernel whi= ch=20 >> doesn't contain that fix. > > Commit f4e342c87776884f0309942a3880ca7e835239f9. > > All it did was to prevent the walker from trying to verify pages in the= > hypervisor range so it doesn't really fix anything. It's just that I am= > surprised to see this warning again. --ssMkJKx553I29pdFKF0oMP1rtNRG1rurf-- --fbjN4vJNsC4kA1ka6lejE9lFHF08dkpgu Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJYh8qbAAoJEIredpCGysGyB4sP/0CBXRQE/AIUP1Sm2P2nQm8d /qy1NOpXFPJZLmg7DGeUqaW3O44Hc6BrFy6iA0PZl39jrJhnvlIddqu+D7raG24F DW10QyYnA/CqfoioUkf4YGTQvERSAIGwHKhcfypjdwucRTrI7wPZA1dInbhvm2tW FCIJNC/Go4NZXBDRtyqrU0z3DAagiOWzjafa4KlKcNh+/uaSvm5HIgQXzx42yZb8 qoeu37k8348ABWvabmSowz37Le4xb42J/QiISSYdmkCTAWhUZnZfRKa+5/jMbunr shHiyM1IaJmvlh5vUrvrNVLGqFDa58stAyPSn9jZczS3vW/5rSAEzRC8Z8jajCwL 82KDfhePjeVPUsmpukSVn+7xG8EMSJg5QsHhyIW5knlWGJEWtYtMQm4p5ir3/cg0 dPAZiY8ODcOjfGb85liJ3AooeStNeBVj4MUNm7dxXyFo1n2rPJ4/T93yGBWNkGQy 6rmlzhzVxIbhHTPwv+N1Hi7kiHA39UvC3PeONLeTTYyiCPWqgYEWQWixqiNGEtmf UUv0lCHkuEuhiStegLCONfrWgOvVdmnxUiZVM3YWTFzEwEvKT1YiSDtbIPUTaEts Fxmn/l4QN0FkL3M/s1dO2if5Nh5QeIOoMLOSKdxOq1cHFXAKTU7x7rOc5JulOyxh P5ktrTMXwOEmXWy7zYR1 =+0hh -----END PGP SIGNATURE----- --fbjN4vJNsC4kA1ka6lejE9lFHF08dkpgu-- --===============1419496806262860922== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KWGVuLWRldmVs IG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVuLm9yZwpodHRwczovL2xpc3RzLnhlbi5v cmcveGVuLWRldmVsCg== --===============1419496806262860922==--