From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH] pci-assign: Do not reset the device unless the kernel supports it Date: Tue, 07 Jun 2011 10:14:22 +0200 Message-ID: <4DEDDDDE.4010209@web.de> References: <4DED470F.4020203@web.de> <1307396894.5901.5.camel@x201> <4DED4EDA.80803@web.de> <4DEDDC1D.7000905@redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig669B1236C67A49530626D82F" Cc: Alex Williamson , Marcelo Tosatti , kvm To: Avi Kivity Return-path: Received: from fmmailgate01.web.de ([217.72.192.221]:47862 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751499Ab1FGIO1 (ORCPT ); Tue, 7 Jun 2011 04:14:27 -0400 In-Reply-To: <4DEDDC1D.7000905@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig669B1236C67A49530626D82F Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 2011-06-07 10:06, Avi Kivity wrote: > On 06/07/2011 01:04 AM, Jan Kiszka wrote: >> On 2011-06-06 23:48, Alex Williamson wrote: >> > On Mon, 2011-06-06 at 23:30 +0200, Jan Kiszka wrote: >> >> From: Jan Kiszka >> >> >> >> At least kernels 2.6.38 and 2.6.39 do not properly support issuing= a >> >> reset on an assigned device and corrupt its config space. Prevent >> >> this by checking for a host kernel with the required support, >> tagged by >> >> the to-be-introduced KVM_CAP_DEVICE_RESET. >> > >> > Wouldn't it be easier just to revert ed78661f in 2.6.39 stable? I >> guess >> > we don't have an option to do that for .38 since stable is done the= re, >> > but there are also some intel-iommu breakages that won't make >> stable for >> > that release. It seems like the userspace invoked reset resolves >> known, >> > demonstrable issues of devices continuing to DMA into guest memory >> while >> > ed78661f is mostly a theoretical change. >> >> Easier would be this patch. But I don't mind reverting the problematic= >> commit in 39, whatever is preferred. We should just resolve the issue >> finally. >=20 > Kernel problems should be solved in the kernel (with exceptions of > course, but don't see the need here). Then please file a revert for stable ASAP. Jan --------------enig669B1236C67A49530626D82F Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAk3t3eEACgkQitSsb3rl5xRyhgCg1BJVdEZXOBvUu9d8un8cm6Q0 DyAAn2iRqxMs5l5FPyerrCs8HEyi7vbf =yYfP -----END PGP SIGNATURE----- --------------enig669B1236C67A49530626D82F--