From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52147) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQpRc-0007OZ-Da for qemu-devel@nongnu.org; Fri, 30 Jun 2017 02:30:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dQpRW-00088s-Gy for qemu-devel@nongnu.org; Fri, 30 Jun 2017 02:30:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50724) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dQpRW-00088X-Ap for qemu-devel@nongnu.org; Fri, 30 Jun 2017 02:30:14 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1C8C7333C0 for ; Fri, 30 Jun 2017 06:30:13 +0000 (UTC) Date: Fri, 30 Jun 2017 14:30:02 +0800 From: Peter Xu Message-ID: <20170630063002.GD24859@pxdev.xzpeter.org> References: <1498710417-7807-1-git-send-email-peterx@redhat.com> <20170629163418-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170629163418-mutt-send-email-mst@kernel.org> Subject: Re: [Qemu-devel] [PATCH] intel_iommu: fix migration breakage on mr switch List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: qemu-devel@nongnu.org, Juan Quintela , Jason Wang , Laurent Vivier , "Dr . David Alan Gilbert" On Thu, Jun 29, 2017 at 04:35:04PM +0300, Michael S. Tsirkin wrote: > On Thu, Jun 29, 2017 at 12:26:57PM +0800, Peter Xu wrote: > > Migration is broken after the vfio integration work: > > > > qemu-kvm: AHCI: Failed to start FIS receive engine: bad FIS receive buffer address > > qemu-kvm: Failed to load ich9_ahci:ahci > > qemu-kvm: error while loading state for instance 0x0 of device '0000:00:1f.2/ich9_ahci' > > qemu-kvm: load of migration failed: Operation not permitted > > > > The problem is that vfio work introduced dynamic memory region > > switching (actually it is also used for future PT mode), and this memory > > region layout is not properly delivered to destination when migration > > happens. Solution is to rebuild the layout in post_load. > > > > Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1459906 > > Fixes: 558e0024 ("intel_iommu: allow dynamic switch of IOMMU region") > > Signed-off-by: Peter Xu > > --- > > hw/i386/intel_iommu.c | 17 +++++++++++++++++ > > 1 file changed, 17 insertions(+) > > > > diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c > > index a9b59bd..36b231d 100644 > > --- a/hw/i386/intel_iommu.c > > +++ b/hw/i386/intel_iommu.c > > @@ -2332,11 +2332,28 @@ static void vtd_iommu_notify_flag_changed(MemoryRegion *iommu, > > } > > } > > > > +static int vtd_post_load(void *opaque, int version_id) > > +{ > > + IntelIOMMUState *iommu = opaque; > > + > > + /* > > + * Since commit 558e00 ("intel_iommu: allow dynamic switch of > > + * IOMMU region"), > > I would drop this part of the comment. It isn't of interest > to people reading code directly, while people reading git > history see the commit log. Ok. Will resend. Thanks. -- Peter Xu