qemu-kvm/SOURCES/kvm-vfio-migration-Free-resources-when-vfio_migration_re.patch
2023-11-07 09:43:59 +00:00

146 lines
5.2 KiB
Diff

From a36fa46369fe9bf2a2174e9ed6ab83042e904066 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= <clg@redhat.com>
Date: Wed, 12 Jul 2023 17:46:57 +0200
Subject: [PATCH 27/37] vfio/migration: Free resources when
vfio_migration_realize fails
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
RH-Author: Cédric Le Goater <clg@redhat.com>
RH-MergeRequest: 179: vfio: live migration support
RH-Bugzilla: 2192818
RH-Acked-by: Eric Auger <eric.auger@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [25/28] b3ab8d3443d4bc12a689dc7d88a94da315814bb7 (clegoate/qemu-kvm-c9s)
Bugzilla: https://bugzilla.redhat.com/2192818
commit 2b43b2995b02
Author: Zhenzhong Duan <zhenzhong.duan@intel.com>
Date: Mon Jul 3 15:15:08 2023 +0800
vfio/migration: Free resources when vfio_migration_realize fails
When vfio_realize() succeeds, hot unplug will call vfio_exitfn()
to free resources allocated in vfio_realize(); when vfio_realize()
fails, vfio_exitfn() is never called and we need to free resources
in vfio_realize().
In the case that vfio_migration_realize() fails,
e.g: with -only-migratable & enable-migration=off, we see below:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,enable-migration=off
0000:81:11.1: Migration disabled
Error: disallowing migration blocker (--only-migratable) for: 0000:81:11.1: Migration is disabled for VFIO device
If we hotplug again we should see same log as above, but we see:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,enable-migration=off
Error: vfio 0000:81:11.1: device is already attached
That's because some references to VFIO device isn't released.
For resources allocated in vfio_migration_realize(), free them by
jumping to out_deinit path with calling a new function
vfio_migration_deinit(). For resources allocated in vfio_realize(),
free them by jumping to de-register path in vfio_realize().
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Fixes: a22651053b59 ("vfio: Make vfio-pci device migration capable")
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
hw/vfio/migration.c | 33 +++++++++++++++++++++++----------
hw/vfio/pci.c | 1 +
2 files changed, 24 insertions(+), 10 deletions(-)
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index e6e5e85f75..e3954570c8 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -802,6 +802,17 @@ static int vfio_migration_init(VFIODevice *vbasedev)
return 0;
}
+static void vfio_migration_deinit(VFIODevice *vbasedev)
+{
+ VFIOMigration *migration = vbasedev->migration;
+
+ remove_migration_state_change_notifier(&migration->migration_state);
+ qemu_del_vm_change_state_handler(migration->vm_state);
+ unregister_savevm(VMSTATE_IF(vbasedev->dev), "vfio", vbasedev);
+ vfio_migration_free(vbasedev);
+ vfio_unblock_multiple_devices_migration();
+}
+
static int vfio_block_migration(VFIODevice *vbasedev, Error *err, Error **errp)
{
int ret;
@@ -866,7 +877,7 @@ int vfio_migration_realize(VFIODevice *vbasedev, Error **errp)
error_setg(&err,
"%s: VFIO device doesn't support device dirty tracking",
vbasedev->name);
- return vfio_block_migration(vbasedev, err, errp);
+ goto add_blocker;
}
warn_report("%s: VFIO device doesn't support device dirty tracking",
@@ -875,29 +886,31 @@ int vfio_migration_realize(VFIODevice *vbasedev, Error **errp)
ret = vfio_block_multiple_devices_migration(vbasedev, errp);
if (ret) {
- return ret;
+ goto out_deinit;
}
if (vfio_viommu_preset(vbasedev)) {
error_setg(&err, "%s: Migration is currently not supported "
"with vIOMMU enabled", vbasedev->name);
- return vfio_block_migration(vbasedev, err, errp);
+ goto add_blocker;
}
trace_vfio_migration_realize(vbasedev->name);
return 0;
+
+add_blocker:
+ ret = vfio_block_migration(vbasedev, err, errp);
+out_deinit:
+ if (ret) {
+ vfio_migration_deinit(vbasedev);
+ }
+ return ret;
}
void vfio_migration_exit(VFIODevice *vbasedev)
{
if (vbasedev->migration) {
- VFIOMigration *migration = vbasedev->migration;
-
- remove_migration_state_change_notifier(&migration->migration_state);
- qemu_del_vm_change_state_handler(migration->vm_state);
- unregister_savevm(VMSTATE_IF(vbasedev->dev), "vfio", vbasedev);
- vfio_migration_free(vbasedev);
- vfio_unblock_multiple_devices_migration();
+ vfio_migration_deinit(vbasedev);
}
if (vbasedev->migration_blocker) {
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 922c81872c..037b7d4176 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3234,6 +3234,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
ret = vfio_migration_realize(vbasedev, errp);
if (ret) {
error_report("%s: Migration disabled", vbasedev->name);
+ goto out_deregister;
}
}
--
2.39.3