From 231d80e36c0788378d87ad4ee376ea87dc43745d Mon Sep 17 00:00:00 2001
From: Cornelia Huck <cohuck@redhat.com>
Date: Wed, 17 Apr 2019 13:57:30 +0100
Subject: [PATCH 13/24] s390x/pci: Ignore the unplug call if we already have a
 release_timer

RH-Author: Cornelia Huck <cohuck@redhat.com>
Message-id: <20190417135741.25297-14-cohuck@redhat.com>
Patchwork-id: 85791
O-Subject: [RHEL-8.1.0 qemu-kvm PATCH v2 13/24] s390x/pci: Ignore the unplug call if we already have a release_timer
Bugzilla: 1699070
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Jens Freimann <jfreimann@redhat.com>

From: David Hildenbrand <david@redhat.com>

... otherwise two successive calls to qdev_unplug() (e.g. by an impatient
user) will effectively overwrite pbdev->release_timer, resulting in a
memory leak. We are already processing the unplug.

If there is already a release_timer, the unplug will be performed after
the timeout.

Can be easily triggered by
(hmp) device_add virtio-mouse-pci,id=test
(hmp) stop
(hmp) device_del test
(hmp) device_del test

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190114103110.10909-5-david@redhat.com>
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
(cherry picked from commit 3549f8c9e4f0ef1c3417ff43b2164f68ad34b922)
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
 hw/s390x/s390-pci-bus.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index ea0c74c..24a0d78 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -972,6 +972,9 @@ static void s390_pcihost_unplug(HotplugHandler *hotplug_dev, DeviceState *dev,
     case ZPCI_FS_STANDBY:
         break;
     default:
+        if (pbdev->release_timer) {
+            return;
+        }
         s390_pci_generate_plug_event(HP_EVENT_DECONFIGURE_REQUEST,
                                      pbdev->fh, pbdev->fid);
         pbdev->release_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
-- 
1.8.3.1