From patchwork Wed Dec 9 05:52:43 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jianzhong,Chang" X-Patchwork-Id: 554236 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C3A3514030F for ; Wed, 9 Dec 2015 16:55:46 +1100 (AEDT) Received: from localhost ([::1]:34730 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a6Xj6-0004qr-OO for incoming@patchwork.ozlabs.org; Wed, 09 Dec 2015 00:55:44 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50648) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a6Xij-0004Yy-Pl for qemu-devel@nongnu.org; Wed, 09 Dec 2015 00:55:22 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a6Xig-0003PE-Hm for qemu-devel@nongnu.org; Wed, 09 Dec 2015 00:55:21 -0500 Received: from mga09.intel.com ([134.134.136.24]:53604) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a6Xig-0003Os-BD for qemu-devel@nongnu.org; Wed, 09 Dec 2015 00:55:18 -0500 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 08 Dec 2015 21:55:15 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,402,1444719600"; d="scan'208";a="867725239" Received: from unknown (HELO lm1.sh.intel.com) ([10.239.48.133]) by orsmga002.jf.intel.com with ESMTP; 08 Dec 2015 21:55:13 -0800 From: "Jianzhong,Chang" To: qemu-devel@nongnu.org Date: Wed, 9 Dec 2015 13:52:43 +0800 Message-Id: <1449640363-7118-1-git-send-email-jianzhongx.chang@intel.com> X-Mailer: git-send-email 1.7.1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 134.134.136.24 Cc: tianyu.lan@intel.com, konrad.wilk@oracle.com, liang.z.li@intel.com, xen-devel@lists.xen.org, "Jianzhong, Chang" , pbonzini@redhat.com, stefano.stabellini@eu.citrix.com Subject: [Qemu-devel] [PATCH v2] xen_pt: fix failure of attaching & detaching a PCI device to VM repeatedly X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Add pci = [ '$VF_BDF1', '$VF_BDF2', '$VF_BDF3'] in hvm guest configuration file. After the guest boot up, detach the VFs in sequence by "xl pci-detach $DOMID $VF_BDF1" "xl pci-detach $DOMID $VF_BDF2" "xl pci-detach $DOMID $VF_BDF3" and reattach the VFs in sequence by "xl pci-attach $DOMID $VF_BDF1" "xl pci-attach $DOMID $VF_BDF2" "xl pci-attach $DOMID $VF_BDF3" An error message will be reported like this: "libxl: error: libxl_qmp.c:287:qmp_handle_error_response: received an error message from QMP server: Duplicate ID 'pci-pt-07_10.1' for device" When xen_pt_region_add/del() is called, MemoryRegion may not belong to the XenPCIPassthroughState. xen_pt_region_update() checks it but memory_region_ref/unref() does not. This case causes obj->ref issue and affects the release of related objects. So, memory_region_ref/unref() is moved from xen_pt_region_add/del to xen_pt_region_update. Signed-off-by: Jianzhong,Chang --- hw/xen/xen_pt.c | 13 ++++++++----- 1 files changed, 8 insertions(+), 5 deletions(-) diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c index aa96288..b963208 100644 --- a/hw/xen/xen_pt.c +++ b/hw/xen/xen_pt.c @@ -590,11 +590,15 @@ static void xen_pt_region_update(XenPCIPassthroughState *s, if (bar == -1 && (!s->msix || &s->msix->mmio != mr)) { return; } - + if (adding) { + memory_region_ref(mr); + } if (s->msix && &s->msix->mmio == mr) { if (adding) { s->msix->mmio_base_addr = sec->offset_within_address_space; rc = xen_pt_msix_update_remap(s, s->msix->bar_index); + } else { + memory_region_unref(mr); } return; } @@ -635,6 +639,9 @@ static void xen_pt_region_update(XenPCIPassthroughState *s, adding ? "create new" : "remove old", errno); } } + if (!adding) { + memory_region_unref(mr); + } } static void xen_pt_region_add(MemoryListener *l, MemoryRegionSection *sec) @@ -642,7 +649,6 @@ static void xen_pt_region_add(MemoryListener *l, MemoryRegionSection *sec) XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState, memory_listener); - memory_region_ref(sec->mr); xen_pt_region_update(s, sec, true); } @@ -652,7 +658,6 @@ static void xen_pt_region_del(MemoryListener *l, MemoryRegionSection *sec) memory_listener); xen_pt_region_update(s, sec, false); - memory_region_unref(sec->mr); } static void xen_pt_io_region_add(MemoryListener *l, MemoryRegionSection *sec) @@ -660,7 +665,6 @@ static void xen_pt_io_region_add(MemoryListener *l, MemoryRegionSection *sec) XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState, io_listener); - memory_region_ref(sec->mr); xen_pt_region_update(s, sec, true); } @@ -670,7 +674,6 @@ static void xen_pt_io_region_del(MemoryListener *l, MemoryRegionSection *sec) io_listener); xen_pt_region_update(s, sec, false); - memory_region_unref(sec->mr); } static const MemoryListener xen_pt_memory_listener = {