From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: Bugs in kvm guest migration Date: Sun, 06 Dec 2009 15:55:32 +0100 Message-ID: <4B1BC5E4.9010907@web.de> References: <4B17DB29.9060801@siemens.com> <4B181033.1020804@siemens.com> <4B18C176.7050105@redhat.com> <4B190DC8.60005@siemens.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigBDAB7757951151F3B2250E25" Cc: Avi Kivity , Marcelo Tosatti , kvm , qemu-devel To: unlisted-recipients:; (no To-header on input) Return-path: Received: from fmmailgate01.web.de ([217.72.192.221]:42854 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933778AbZLFOz1 (ORCPT ); Sun, 6 Dec 2009 09:55:27 -0500 In-Reply-To: <4B190DC8.60005@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigBDAB7757951151F3B2250E25 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Jan Kiszka wrote: > Avi Kivity wrote: >> On 12/03/2009 09:23 PM, Jan Kiszka wrote: >>> Jan Kiszka wrote: >>> =20 >>>> Problem 2 >>>> --------- >>>> Setup: qemu head with vmstate fixes. kvm-kmod master, 64-bit host& = guest. >>>> Effect: The migration target either locks up or reboots immediately.= >>>> I've nailed this down to 84d0b66c778d881eafca2a5d0d66678211c4e861. E= very >>>> kvm module build before that works, everything including and after >>>> 26ede77f536d1bb369527a96c7fe7fdc8ba2f890 shows the effect (everythin= g in >>>> between crashes the host for known reasons). It's still unclear if t= his >>>> is an kvm-kmod wrapping issue of the user-space return notifiers. Wi= ll >>>> check once problem #1 is understood. >>>> =20 >>> It is kernel-related, using kvm.git as host kernel makes no differenc= e. >>> >>> This may now mean that kvm is buggy or that it triggers some msr >>> save/restore related issues in qemu. Digging even deeper... >>> =20 >> Does calling drop_user_return_notifiers() (static in x86.c, will need = >> exporting) in vmx_load_host_state() within the preempt-disable region = help? >> >=20 > Nope. >=20 It was a qemu bug, resolved by "KVM: x86: Fix initial kvm_has_msr_star". Jan --------------enigBDAB7757951151F3B2250E25 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iEYEARECAAYFAksbxeQACgkQitSsb3rl5xST5ACfTER5cP3sZ5XsaaNRVAsdtDeN rNAAn0jjH6W3t540cYVjYnCQ1shQuw3L =i+c6 -----END PGP SIGNATURE----- --------------enigBDAB7757951151F3B2250E25--