[PATCH v5 0/4] tests/qtest: add some tests for virtio-net failover

[PATCH v5 0/4] tests/qtest: add some tests for virtio-net failover

[Laurent Vivier]

This series adds a qtest entry to test virtio-net failover feature.

We check following error cases:

- check missing id on device with failover_pair_id triggers an error
- check a primary device plugged on a bus that doesn't support hotplug
  triggers an error

We check the status of the machine before and after hotplugging cards and
feature negotiation:

- check we don't see the primary device at boot if failover is on
- check we see the primary device at boot if failover is off
- check we don't see the primary device if failover is on
  but failover_pair_id is not the one with on (I think this should be changed)
- check the primary device is plugged after the feature negotiation
- check the result if the primary device is plugged before standby device and
  vice-versa
- check the if the primary device is coldplugged and the standy device
  hotplugged and vice-versa
- check the migration triggers the unplug and the hotplug

There is one preliminary patch in the series:

- PATCH 1 introduces a function to enable PCI bridge.
  Failover needs to be plugged on a pcie-root-port and while
  the root port is not configured the cards behind it are not
  available

v5:
- re-add the wait-unplug test that has been removed from v4 by mistake.

v4:
- rely on query-migrate status to know the migration state rather than
  to wait the STOP event.
- remove the patch to add time out to qtest_qmp_eventwait()

v3:
- fix a bug with ACPI unplug and add the related test

v2:
- remove PATCH 1 that introduced a function that can be replaced by
  qobject_to_json_pretty() (Markus)
- Add migration to a file and from the file to check the card is
  correctly unplugged on the source, and hotplugged on the dest
- Add an ACPI call to eject the card as the kernel would do

Laurent Vivier (4):
  qtest/libqos: add a function to initialize secondary PCI buses
  tests/qtest: add some tests for virtio-net failover
  failover: fix unplug pending detection
  tests/libqtest: update virtio-net failover test

 hw/acpi/pcihp.c                   |  30 +-
 include/hw/pci/pci_bridge.h       |   8 +
 tests/qtest/libqos/pci.c          | 118 ++++++
 tests/qtest/libqos/pci.h          |   1 +
 tests/qtest/meson.build           |   3 +
 tests/qtest/virtio-net-failover.c | 681 ++++++++++++++++++++++++++++++
 6 files changed, 838 insertions(+), 3 deletions(-)
 create mode 100644 tests/qtest/virtio-net-failover.c

-- 
2.33.1

[PATCH v5 1/4] qtest/libqos: add a function to initialize secondary PCI buses

[Laurent Vivier]

Scan the PCI devices to find bridge and set PCI_SECONDARY_BUS and
PCI_SUBORDINATE_BUS (algorithm from seabios)

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
 include/hw/pci/pci_bridge.h |   8 +++
 tests/qtest/libqos/pci.c    | 118 ++++++++++++++++++++++++++++++++++++
 tests/qtest/libqos/pci.h    |   1 +
 3 files changed, 127 insertions(+)

diff --git a/include/hw/pci/pci_bridge.h b/include/hw/pci/pci_bridge.h
index a94d350034bf..30691a6e5728 100644
--- a/include/hw/pci/pci_bridge.h
+++ b/include/hw/pci/pci_bridge.h
@@ -138,6 +138,7 @@ typedef struct PCIBridgeQemuCap {
     uint64_t mem_pref_64; /* Prefetchable memory to reserve (64-bit MMIO) */
 } PCIBridgeQemuCap;
 
+#define REDHAT_PCI_CAP_TYPE_OFFSET      3
 #define REDHAT_PCI_CAP_RESOURCE_RESERVE 1
 
 /*
@@ -152,6 +153,13 @@ typedef struct PCIResReserve {
     uint64_t mem_pref_64;
 } PCIResReserve;
 
+#define REDHAT_PCI_CAP_RES_RESERVE_BUS_RES     4
+#define REDHAT_PCI_CAP_RES_RESERVE_IO          8
+#define REDHAT_PCI_CAP_RES_RESERVE_MEM         16
+#define REDHAT_PCI_CAP_RES_RESERVE_PREF_MEM_32 20
+#define REDHAT_PCI_CAP_RES_RESERVE_PREF_MEM_64 24
+#define REDHAT_PCI_CAP_RES_RESERVE_CAP_SIZE    32
+
 int pci_bridge_qemu_reserve_cap_init(PCIDevice *dev, int cap_offset,
                                PCIResReserve res_reserve, Error **errp);
 
diff --git a/tests/qtest/libqos/pci.c b/tests/qtest/libqos/pci.c
index e1e96189c821..3f0b18f4750b 100644
--- a/tests/qtest/libqos/pci.c
+++ b/tests/qtest/libqos/pci.c
@@ -13,6 +13,8 @@
 #include "qemu/osdep.h"
 #include "pci.h"
 
+#include "hw/pci/pci.h"
+#include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_regs.h"
 #include "qemu/host-utils.h"
 #include "qgraph.h"
@@ -99,6 +101,122 @@ void qpci_device_init(QPCIDevice *dev, QPCIBus *bus, QPCIAddress *addr)
     g_assert(!addr->device_id || device_id == addr->device_id);
 }
 
+static uint8_t qpci_find_resource_reserve_capability(QPCIDevice *dev)
+{
+    uint16_t device_id;
+    uint8_t cap = 0;
+
+    if (qpci_config_readw(dev, PCI_VENDOR_ID) != PCI_VENDOR_ID_REDHAT) {
+        return 0;
+    }
+
+    device_id = qpci_config_readw(dev, PCI_DEVICE_ID);
+
+    if (device_id != PCI_DEVICE_ID_REDHAT_PCIE_RP &&
+        device_id != PCI_DEVICE_ID_REDHAT_BRIDGE) {
+        return 0;
+    }
+
+    do {
+        cap = qpci_find_capability(dev, PCI_CAP_ID_VNDR, cap);
+    } while (cap &&
+             qpci_config_readb(dev, cap + REDHAT_PCI_CAP_TYPE_OFFSET) !=
+             REDHAT_PCI_CAP_RESOURCE_RESERVE);
+    if (cap) {
+        uint8_t cap_len = qpci_config_readb(dev, cap + PCI_CAP_FLAGS);
+        if (cap_len < REDHAT_PCI_CAP_RES_RESERVE_CAP_SIZE) {
+            return 0;
+        }
+    }
+    return cap;
+}
+
+static void qpci_secondary_buses_rec(QPCIBus *qbus, int bus, int *pci_bus)
+{
+    QPCIDevice *dev;
+    uint16_t class;
+    uint8_t pribus, secbus, subbus;
+    int i;
+
+    for (i = 0; i < 32; i++) {
+        dev = qpci_device_find(qbus, QPCI_DEVFN(bus + i, 0));
+        if (dev == NULL) {
+            continue;
+        }
+        class = qpci_config_readw(dev, PCI_CLASS_DEVICE);
+        if (class == PCI_CLASS_BRIDGE_PCI) {
+            qpci_config_writeb(dev, PCI_SECONDARY_BUS, 255);
+            qpci_config_writeb(dev, PCI_SUBORDINATE_BUS, 0);
+        }
+        g_free(dev);
+    }
+
+    for (i = 0; i < 32; i++) {
+        dev = qpci_device_find(qbus, QPCI_DEVFN(bus + i, 0));
+        if (dev == NULL) {
+            continue;
+        }
+        class = qpci_config_readw(dev, PCI_CLASS_DEVICE);
+        if (class != PCI_CLASS_BRIDGE_PCI) {
+            continue;
+        }
+
+        pribus = qpci_config_readb(dev, PCI_PRIMARY_BUS);
+        if (pribus != bus) {
+            qpci_config_writeb(dev, PCI_PRIMARY_BUS, bus);
+        }
+
+        secbus = qpci_config_readb(dev, PCI_SECONDARY_BUS);
+        (*pci_bus)++;
+        if (*pci_bus != secbus) {
+            secbus = *pci_bus;
+            qpci_config_writeb(dev, PCI_SECONDARY_BUS, secbus);
+        }
+
+        subbus = qpci_config_readb(dev, PCI_SUBORDINATE_BUS);
+        qpci_config_writeb(dev, PCI_SUBORDINATE_BUS, 255);
+
+        qpci_secondary_buses_rec(qbus, secbus << 5, pci_bus);
+
+        if (subbus != *pci_bus) {
+            uint8_t res_bus = *pci_bus;
+            uint8_t cap = qpci_find_resource_reserve_capability(dev);
+
+            if (cap) {
+                uint32_t tmp_res_bus;
+
+                tmp_res_bus = qpci_config_readl(dev, cap +
+                                            REDHAT_PCI_CAP_RES_RESERVE_BUS_RES);
+                if (tmp_res_bus != (uint32_t)-1) {
+                    res_bus = tmp_res_bus & 0xFF;
+                    if ((uint8_t)(res_bus + secbus) < secbus ||
+                        (uint8_t)(res_bus + secbus) < res_bus) {
+                        res_bus = 0;
+                    }
+                    if (secbus + res_bus > *pci_bus) {
+                        res_bus = secbus + res_bus;
+                    }
+                }
+            }
+            subbus = res_bus;
+            *pci_bus = res_bus;
+        }
+
+        qpci_config_writeb(dev, PCI_SUBORDINATE_BUS, subbus);
+        g_free(dev);
+    }
+}
+
+int qpci_secondary_buses_init(QPCIBus *bus)
+{
+    int last_bus = 0;
+
+    qpci_secondary_buses_rec(bus, 0, &last_bus);
+
+    return last_bus;
+}
+
+
 void qpci_device_enable(QPCIDevice *dev)
 {
     uint16_t cmd;
diff --git a/tests/qtest/libqos/pci.h b/tests/qtest/libqos/pci.h
index ee64fdecbda8..becb800f9e6a 100644
--- a/tests/qtest/libqos/pci.h
+++ b/tests/qtest/libqos/pci.h
@@ -81,6 +81,7 @@ void qpci_device_foreach(QPCIBus *bus, int vendor_id, int device_id,
                          void *data);
 QPCIDevice *qpci_device_find(QPCIBus *bus, int devfn);
 void qpci_device_init(QPCIDevice *dev, QPCIBus *bus, QPCIAddress *addr);
+int qpci_secondary_buses_init(QPCIBus *bus);
 
 bool qpci_has_buggy_msi(QPCIDevice *dev);
 bool qpci_check_buggy_msi(QPCIDevice *dev);
-- 
2.33.1

[PATCH v5 2/4] tests/qtest: add some tests for virtio-net failover

[Laurent Vivier]

Add test cases to test several error cases that must be
generated by invalid failover configuration.

Add a combination of coldplug and hotplug test cases to be
sure the primary is correctly managed according the
presence or not of the STANDBY feature.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
 tests/qtest/meson.build           |   3 +
 tests/qtest/virtio-net-failover.c | 658 ++++++++++++++++++++++++++++++
 2 files changed, 661 insertions(+)
 create mode 100644 tests/qtest/virtio-net-failover.c

diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index c9d8458062ff..6d66bf522156 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -22,6 +22,9 @@ qtests_generic = \
   (config_all_devices.has_key('CONFIG_VIRTIO_SCSI') ? ['fuzz-virtio-scsi-test'] : []) + \
   (config_all_devices.has_key('CONFIG_SB16') ? ['fuzz-sb16-test'] : []) + \
   (config_all_devices.has_key('CONFIG_SDHCI_PCI') ? ['fuzz-sdcard-test'] : []) + \
+  (config_all_devices.has_key('CONFIG_VIRTIO_NET') and \
+   config_all_devices.has_key('CONFIG_Q35') and \
+   config_all_devices.has_key('CONFIG_VIRTIO_PCI') ? ['virtio-net-failover'] : []) + \
   [
   'cdrom-test',
   'device-introspect-test',
diff --git a/tests/qtest/virtio-net-failover.c b/tests/qtest/virtio-net-failover.c
new file mode 100644
index 000000000000..11fa0b21f8bf
--- /dev/null
+++ b/tests/qtest/virtio-net-failover.c
@@ -0,0 +1,658 @@
+#include "qemu/osdep.h"
+#include "libqos/libqtest.h"
+#include "libqos/pci.h"
+#include "libqos/pci-pc.h"
+#include "qapi/qmp/qdict.h"
+#include "qapi/qmp/qlist.h"
+#include "qapi/qmp/qjson.h"
+#include "libqos/malloc-pc.h"
+#include "libqos/virtio-pci.h"
+#include "hw/pci/pci.h"
+
+#define ACPI_PCIHP_ADDR_ICH9    0x0cc0
+#define PCI_EJ_BASE             0x0008
+
+#define BASE_MACHINE "-M q35 -nodefaults " \
+    "-device pcie-root-port,id=root0,addr=0x1,bus=pcie.0,chassis=1 " \
+    "-device pcie-root-port,id=root1,addr=0x2,bus=pcie.0,chassis=2 "
+
+#define MAC_PRIMARY "52:54:00:11:11:11"
+#define MAC_STANDBY "52:54:00:22:22:22"
+
+static QGuestAllocator guest_malloc;
+static QPCIBus *pcibus;
+
+static QTestState *machine_start(const char *args)
+{
+    QTestState *qts;
+    QPCIDevice *dev;
+
+    qts = qtest_init(args);
+
+    pc_alloc_init(&guest_malloc, qts, 0);
+    pcibus = qpci_new_pc(qts, &guest_malloc);
+    g_assert(qpci_secondary_buses_init(pcibus) == 2);
+
+    dev = qpci_device_find(pcibus, QPCI_DEVFN(1, 0)); /* root0 */
+    g_assert_nonnull(dev);
+
+    qpci_device_enable(dev);
+    qpci_iomap(dev, 4, NULL);
+
+    g_free(dev);
+
+    dev = qpci_device_find(pcibus, QPCI_DEVFN(2, 0)); /* root1 */
+    g_assert_nonnull(dev);
+
+    qpci_device_enable(dev);
+    qpci_iomap(dev, 4, NULL);
+
+    g_free(dev);
+
+    return qts;
+}
+
+static void machine_stop(QTestState *qts)
+{
+    qpci_free_pc(pcibus);
+    alloc_destroy(&guest_malloc);
+    qtest_quit(qts);
+}
+
+static void test_error_id(void)
+{
+    QTestState *qts;
+    QDict *resp;
+    QDict *err;
+
+    qts = machine_start(BASE_MACHINE
+                        "-device virtio-net,bus=root0,id=standby0,failover=on");
+
+    resp = qtest_qmp(qts, "{'execute': 'device_add',"
+                          "'arguments': {"
+                          "'driver': 'virtio-net',"
+                          "'bus': 'root1',"
+                          "'failover_pair_id': 'standby0'"
+                          "} }");
+    g_assert(qdict_haskey(resp, "error"));
+
+    err = qdict_get_qdict(resp, "error");
+    g_assert(qdict_haskey(err, "desc"));
+
+    g_assert_cmpstr(qdict_get_str(err, "desc"), ==,
+                    "Device with failover_pair_id needs to have id");
+
+    qobject_unref(resp);
+
+    machine_stop(qts);
+}
+
+static void test_error_pcie(void)
+{
+    QTestState *qts;
+    QDict *resp;
+    QDict *err;
+
+    qts = machine_start(BASE_MACHINE
+                        "-device virtio-net,bus=root0,id=standby0,failover=on");
+
+    resp = qtest_qmp(qts, "{'execute': 'device_add',"
+                          "'arguments': {"
+                          "'driver': 'virtio-net',"
+                          "'id': 'primary0',"
+                          "'bus': 'pcie.0',"
+                          "'failover_pair_id': 'standby0'"
+                          "} }");
+    g_assert(qdict_haskey(resp, "error"));
+
+    err = qdict_get_qdict(resp, "error");
+    g_assert(qdict_haskey(err, "desc"));
+
+    g_assert_cmpstr(qdict_get_str(err, "desc"), ==,
+                    "Bus 'pcie.0' does not support hotplugging");
+
+    qobject_unref(resp);
+
+    machine_stop(qts);
+}
+
+static QDict *find_device(QDict *bus, const char *name)
+{
+    const QObject *obj;
+    QList *devices;
+    QList *list;
+
+    devices = qdict_get_qlist(bus, "devices");
+    if (devices == NULL) {
+        return NULL;
+    }
+
+    list = qlist_copy(devices);
+    while ((obj = qlist_pop(list))) {
+        QDict *device;
+
+        device = qobject_to(QDict, obj);
+
+        if (qdict_haskey(device, "pci_bridge")) {
+            QDict *bridge;
+            QDict *bridge_device;
+
+            bridge = qdict_get_qdict(device, "pci_bridge");
+
+            if (qdict_haskey(bridge, "devices")) {
+                bridge_device = find_device(bridge, name);
+                if (bridge_device) {
+                    qobject_unref(list);
+                    return bridge_device;
+                }
+            }
+        }
+
+        if (!qdict_haskey(device, "qdev_id")) {
+            continue;
+        }
+
+        if (strcmp(qdict_get_str(device, "qdev_id"), name) == 0) {
+            qobject_ref(device);
+            qobject_unref(list);
+            return device;
+        }
+    }
+    qobject_unref(list);
+
+    return NULL;
+}
+
+static QDict *get_bus(QTestState *qts, int num)
+{
+    QObject *obj;
+    QDict *resp;
+    QList *ret;
+
+    resp = qtest_qmp(qts, "{ 'execute': 'query-pci' }");
+    g_assert(qdict_haskey(resp, "return"));
+
+    ret = qdict_get_qlist(resp, "return");
+    g_assert_nonnull(ret);
+
+    while ((obj = qlist_pop(ret))) {
+        QDict *bus;
+
+        bus = qobject_to(QDict, obj);
+        if (!qdict_haskey(bus, "bus")) {
+            continue;
+        }
+        if (qdict_get_int(bus, "bus") == num) {
+            qobject_ref(bus);
+            qobject_unref(resp);
+            return bus;
+        }
+    }
+    qobject_unref(resp);
+
+    return NULL;
+}
+
+static char *get_mac(QTestState *qts, const char *name)
+{
+    QDict *resp;
+    char *mac;
+
+    resp = qtest_qmp(qts, "{ 'execute': 'qom-get', "
+                     "'arguments': { "
+                     "'path': %s, "
+                     "'property': 'mac' } }", name);
+
+    g_assert(qdict_haskey(resp, "return"));
+
+    mac = g_strdup( qdict_get_str(resp, "return"));
+
+    qobject_unref(resp);
+
+    return mac;
+}
+
+static void check_cards(QTestState *qts, bool standby, bool primary)
+{
+    QDict *device;
+    QDict *bus;
+    char *mac;
+
+    bus = get_bus(qts, 0);
+    device = find_device(bus, "standby0");
+    if (standby) {
+        g_assert_nonnull(device);
+        qobject_unref(device);
+
+        mac = get_mac(qts, "/machine/peripheral/standby0");
+        g_assert_cmpstr(mac, ==, MAC_STANDBY);
+        g_free(mac);
+    } else {
+       g_assert_null(device);
+    }
+
+    device = find_device(bus, "primary0");
+    if (primary) {
+        g_assert_nonnull(device);
+        qobject_unref(device);
+
+        mac = get_mac(qts, "/machine/peripheral/primary0");
+        g_assert_cmpstr(mac, ==, MAC_PRIMARY);
+        g_free(mac);
+    } else {
+       g_assert_null(device);
+    }
+    qobject_unref(bus);
+}
+
+static void test_on(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                        "-netdev user,id=hs0 "
+                        "-device virtio-net,bus=root0,id=standby0,"
+                        "failover=on,netdev=hs0,mac="MAC_STANDBY" "
+                        "-device virtio-net,bus=root1,id=primary0,"
+                        "failover_pair_id=standby0,netdev=hs1,mac="MAC_PRIMARY);
+
+    check_cards(qts, true, false); /* standby, no primary */
+
+    machine_stop(qts);
+}
+
+static void test_on_mismatch(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-device virtio-net,bus=root0,id=standby0,"
+                     "failover=on,netdev=hs0,mac="MAC_STANDBY" "
+                     "-netdev user,id=hs1 "
+                     "-device virtio-net,bus=root1,id=primary0,"
+                     "failover_pair_id=standby1,netdev=hs1,mac="MAC_PRIMARY);
+
+    check_cards(qts, true, true); /* standby, primary (but no failover) */
+
+    machine_stop(qts);
+}
+
+static void test_off(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-device virtio-net,bus=root0,id=standby0,"
+                     "failover=off,netdev=hs0,mac="MAC_STANDBY" "
+                     "-netdev user,id=hs1 "
+                     "-device virtio-net,bus=root1,id=primary0,"
+                     "failover_pair_id=standby0,netdev=hs1,mac="MAC_PRIMARY);
+
+    check_cards(qts, true, true); /* standby, primary (but no failover) */
+
+    machine_stop(qts);
+}
+
+static void start_virtio_net(QTestState *qts, int bus, int slot)
+{
+    QVirtioPCIDevice *dev;
+    uint64_t features;
+    QPCIAddress addr;
+    QDict *resp;
+    QDict *data;
+
+    addr.devfn = QPCI_DEVFN((bus << 5) + slot, 0);
+    dev = virtio_pci_new(pcibus, &addr);
+    g_assert_nonnull(dev);
+    qvirtio_pci_device_enable(dev);
+    qvirtio_start_device(&dev->vdev);
+    features = qvirtio_get_features(&dev->vdev);
+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
+                            (1ull << VIRTIO_RING_F_INDIRECT_DESC) |
+                            (1ull << VIRTIO_RING_F_EVENT_IDX));
+    qvirtio_set_features(&dev->vdev, features);
+    qvirtio_set_driver_ok(&dev->vdev);
+
+    resp = qtest_qmp_eventwait_ref(qts, "FAILOVER_NEGOTIATED");
+    g_assert(qdict_haskey(resp, "data"));
+
+    data = qdict_get_qdict(resp, "data");
+    g_assert(qdict_haskey(data, "device-id"));
+    g_assert_cmpstr(qdict_get_str(data, "device-id"), ==, "standby0");
+
+    qobject_unref(resp);
+}
+
+static void test_enabled(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-device virtio-net,bus=root0,id=standby0,"
+                     "failover=on,netdev=hs0,mac="MAC_STANDBY" "
+                     "-netdev user,id=hs1 "
+                     "-device virtio-net,bus=root1,id=primary0,"
+                     "failover_pair_id=standby0,netdev=hs1,mac="MAC_PRIMARY" "
+                     );
+
+    check_cards(qts, true, false); /* standby, no primary */
+
+    start_virtio_net(qts, 1, 0);
+
+    check_cards(qts, true, true); /* standby, primary with failover */
+
+    machine_stop(qts);
+}
+
+static void test_hotplug_1(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-device virtio-net,bus=root0,id=standby0,"
+                     "failover=on,netdev=hs0,mac="MAC_STANDBY" "
+                     "-netdev user,id=hs1 "
+                     );
+
+    check_cards(qts, true, false); /* no standby, no primary */
+
+    start_virtio_net(qts, 1, 0);
+
+    check_cards(qts, true, false);
+
+    qtest_qmp_device_add(qts, "virtio-net", "primary0",
+                         "{'bus': 'root1',"
+                         "'failover_pair_id': 'standby0',"
+                         "'netdev': 'hs1',"
+                         "'mac': '"MAC_PRIMARY"'}");
+
+    check_cards(qts, true, true);
+
+    machine_stop(qts);
+}
+
+static void test_hotplug_1_reverse(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-netdev user,id=hs1 "
+                     "-device virtio-net,bus=root1,id=primary0,"
+                     "failover_pair_id=standby0,netdev=hs1,mac="MAC_PRIMARY" "
+                     );
+
+    check_cards(qts, false, true);
+
+    qtest_qmp_device_add(qts, "virtio-net", "standby0",
+                         "{'bus': 'root0',"
+                         "'failover': 'on',"
+                         "'netdev': 'hs0',"
+                         "'mac': '"MAC_STANDBY"'}");
+
+    check_cards(qts, true, true); /* XXX: sounds like a bug */
+
+    start_virtio_net(qts, 1, 0);
+
+    check_cards(qts, true, true);
+
+    machine_stop(qts);
+}
+
+static void test_hotplug_2(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-netdev user,id=hs1 "
+                     );
+
+    check_cards(qts, false, false); /* no standby, no primary */
+
+    qtest_qmp_device_add(qts, "virtio-net", "standby0",
+                         "{'bus': 'root0',"
+                         "'failover': 'on',"
+                         "'netdev': 'hs0',"
+                         "'mac': '"MAC_STANDBY"'}");
+
+    check_cards(qts, true, false);
+
+    start_virtio_net(qts, 1, 0);
+
+    check_cards(qts, true, false);
+
+    qtest_qmp_device_add(qts, "virtio-net", "primary0",
+                         "{'bus': 'root1',"
+                         "'failover_pair_id': 'standby0',"
+                         "'netdev': 'hs1',"
+                         "'mac': '"MAC_PRIMARY"'}");
+
+    check_cards(qts, true, true);
+
+    machine_stop(qts);
+}
+
+static void test_hotplug_2_reverse(void)
+{
+    QTestState *qts;
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-netdev user,id=hs1 "
+                     );
+
+    check_cards(qts, false, false); /* no standby, no primary */
+
+    qtest_qmp_device_add(qts, "virtio-net", "primary0",
+                         "{'bus': 'root1',"
+                         "'failover_pair_id': 'standby0',"
+                         "'netdev': 'hs1',"
+                         "'mac': '"MAC_PRIMARY"'}");
+
+    check_cards(qts, false, true);
+
+    qtest_qmp_device_add(qts, "virtio-net", "standby0",
+                         "{'bus': 'root0',"
+                         "'failover': 'on',"
+                         "'netdev': 'hs0',"
+                         "'rombar': 0,"
+                         "'romfile': '',"
+                         "'mac': '"MAC_STANDBY"'}");
+
+    check_cards(qts, true, true); /* XXX: sounds like a bug */
+
+    start_virtio_net(qts, 1, 0);
+
+    check_cards(qts, true, true);
+
+    machine_stop(qts);
+}
+
+static QDict *migrate_status(QTestState *qts)
+{
+    QDict *resp, *ret;
+
+    resp = qtest_qmp(qts, "{ 'execute': 'query-migrate' }");
+    g_assert(qdict_haskey(resp, "return"));
+
+    ret = qdict_get_qdict(resp, "return");
+    g_assert(qdict_haskey(ret, "status"));
+    qobject_ref(ret);
+    qobject_unref(resp);
+
+    return ret;
+}
+
+static void test_outmigrate(gconstpointer opaque)
+{
+    QTestState *qts;
+    QDict *resp, *args, *data, *ret;
+    g_autofree gchar *uri = g_strdup_printf("exec: cat > %s", (gchar *)opaque);
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-netdev user,id=hs1 "
+                     );
+
+    check_cards(qts, false, false); /* no standby, no primary */
+
+    qtest_qmp_device_add(qts, "virtio-net", "standby0",
+                         "{'bus': 'root0',"
+                         "'failover': 'on',"
+                         "'netdev': 'hs0',"
+                         "'mac': '"MAC_STANDBY"'}");
+
+    check_cards(qts, true, false);
+
+    start_virtio_net(qts, 1, 0);
+
+    check_cards(qts, true, false);
+
+    qtest_qmp_device_add(qts, "virtio-net", "primary0",
+                         "{'bus': 'root1',"
+                         "'failover_pair_id': 'standby0',"
+                         "'netdev': 'hs1',"
+                         "'rombar': 0,"
+                         "'romfile': '',"
+                         "'mac': '"MAC_PRIMARY"'}");
+
+    check_cards(qts, true, true);
+
+    args = qdict_from_jsonf_nofail("{}");
+    g_assert_nonnull(args);
+    qdict_put_str(args, "uri", uri);
+
+    resp = qtest_qmp(qts, "{ 'execute': 'migrate', 'arguments': %p}", args);
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* the event is sent whan QEMU asks the OS to unplug the card */
+    resp = qtest_qmp_eventwait_ref(qts, "UNPLUG_PRIMARY");
+    g_assert(qdict_haskey(resp, "data"));
+
+    data = qdict_get_qdict(resp, "data");
+    g_assert(qdict_haskey(data, "device-id"));
+    g_assert_cmpstr(qdict_get_str(data, "device-id"), ==, "primary0");
+
+    qobject_unref(resp);
+
+    qtest_outl(qts, ACPI_PCIHP_ADDR_ICH9 + PCI_EJ_BASE, 1);
+
+    qtest_qmp_eventwait(qts, "STOP");
+
+    ret = migrate_status(qts);
+    g_assert_cmpstr(qdict_get_str(ret, "status"), ==, "completed");
+    qobject_unref(ret);
+
+    /*
+     * in fact, the card is ejected from the point of view of kernel
+     * but not really from QEMU to be able to hotplug it back if
+     * migration fails. So we can't check that:
+     *   check_cards(qts, true, false);
+     */
+
+    machine_stop(qts);
+}
+
+static void test_inmigrate(gconstpointer opaque)
+{
+    QTestState *qts;
+    QDict *resp, *args, *ret;
+    g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
+
+    qts = machine_start(BASE_MACHINE
+                     "-netdev user,id=hs0 "
+                     "-netdev user,id=hs1 "
+                     "-incoming defer "
+                     );
+
+    check_cards(qts, false, false); /* no standby, no primary */
+
+    qtest_qmp_device_add(qts, "virtio-net", "standby0",
+                         "{'bus': 'root0',"
+                         "'failover': 'on',"
+                         "'netdev': 'hs0',"
+                         "'mac': '"MAC_STANDBY"'}");
+
+    check_cards(qts, true, false);
+
+    qtest_qmp_device_add(qts, "virtio-net", "primary0",
+                         "{'bus': 'root1',"
+                         "'failover_pair_id': 'standby0',"
+                         "'netdev': 'hs1',"
+                         "'rombar': 0,"
+                         "'romfile': '',"
+                         "'mac': '"MAC_PRIMARY"'}");
+
+    check_cards(qts, true, false);
+
+    args = qdict_from_jsonf_nofail("{}");
+    g_assert_nonnull(args);
+    qdict_put_str(args, "uri", uri);
+
+    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
+                     args);
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    qtest_qmp_eventwait(qts, "MIGRATION");
+    qtest_qmp_eventwait(qts, "FAILOVER_NEGOTIATED");
+
+    check_cards(qts, true, true);
+
+    qtest_qmp_eventwait(qts, "RESUME");
+
+    ret = migrate_status(qts);
+    g_assert_cmpstr(qdict_get_str(ret, "status"), ==, "completed");
+    qobject_unref(ret);
+
+    machine_stop(qts);
+}
+
+int main(int argc, char **argv)
+{
+    gchar *tmpfile = g_strdup_printf("/tmp/failover_test_migrate-%u-%u",
+                                     getpid(), g_test_rand_int());
+    const char *arch;
+    int ret;
+
+    g_test_init(&argc, &argv, NULL);
+
+    arch = qtest_get_arch();
+    if (strcmp(arch, "i386") && strcmp(arch, "x86_64")) {
+        g_test_message("Skipping test for non-x86");
+        return g_test_run();
+    }
+
+    qtest_add_func("failover-virtio-net/params/error/id", test_error_id);
+    qtest_add_func("failover-virtio-net/params/error/pcie", test_error_pcie);
+    qtest_add_func("failover-virtio-net/params/error/on", test_on);
+    qtest_add_func("failover-virtio-net/params/error/on_mismatch",
+                   test_on_mismatch);
+    qtest_add_func("failover-virtio-net/params/error/off", test_off);
+    qtest_add_func("failover-virtio-net/params/error/enabled", test_enabled);
+    qtest_add_func("failover-virtio-net/params/error/hotplug_1",
+                   test_hotplug_1);
+    qtest_add_func("failover-virtio-net/params/error/hotplug_1_reverse",
+                   test_hotplug_1_reverse);
+    qtest_add_func("failover-virtio-net/params/error/hotplug_2",
+                   test_hotplug_2);
+    qtest_add_func("failover-virtio-net/params/error/hotplug_2_reverse",
+                   test_hotplug_2_reverse);
+    qtest_add_data_func("failover-virtio-net/params/error/outmigrate",
+                   tmpfile, test_outmigrate);
+    qtest_add_data_func("failover-virtio-net/params/error/inmigrate",
+                   tmpfile, test_inmigrate);
+
+    ret = g_test_run();
+
+    unlink(tmpfile);
+    g_free(tmpfile);
+
+    return ret;
+}
-- 
2.33.1

[PATCH v5 3/4] failover: fix unplug pending detection

[Laurent Vivier]

Failover needs to detect the end of the PCI unplug to start migration
after the VFIO card has been unplugged.

To do that, a flag is set in pcie_cap_slot_unplug_request_cb() and reset in
pcie_unplug_device().

But since
    17858a169508 ("hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35")
we have switched to ACPI unplug and these functions are not called anymore
and the flag not set. So failover migration is not able to detect if card
is really unplugged and acts as it's done as soon as it's started. So it
doesn't wait the end of the unplug to start the migration. We don't see any
problem when we test that because ACPI unplug is faster than PCIe native
hotplug and when the migration really starts the unplug operation is
already done.

See c000a9bd06ea ("pci: mark device having guest unplug request pending")
    a99c4da9fc2a ("pci: mark devices partially unplugged")

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Ani Sinha <ani@anisinha.ca>
---
 hw/acpi/pcihp.c | 30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
index f610a25d2ef9..30405b5113d7 100644
--- a/hw/acpi/pcihp.c
+++ b/hw/acpi/pcihp.c
@@ -222,9 +222,27 @@ static void acpi_pcihp_eject_slot(AcpiPciHpState *s, unsigned bsel, unsigned slo
         PCIDevice *dev = PCI_DEVICE(qdev);
         if (PCI_SLOT(dev->devfn) == slot) {
             if (!acpi_pcihp_pc_no_hotplug(s, dev)) {
-                hotplug_ctrl = qdev_get_hotplug_handler(qdev);
-                hotplug_handler_unplug(hotplug_ctrl, qdev, &error_abort);
-                object_unparent(OBJECT(qdev));
+                /*
+                 * partially_hotplugged is used by virtio-net failover:
+                 * failover has asked the guest OS to unplug the device
+                 * but we need to keep some references to the device
+                 * to be able to plug it back in case of failure so
+                 * we don't execute hotplug_handler_unplug().
+                 */
+                if (dev->partially_hotplugged) {
+                    /*
+                     * pending_deleted_event is set to true when
+                     * virtio-net failover asks to unplug the device,
+                     * and set to false here when the operation is done
+                     * This is used by the migration loop to detect the
+                     * end of the operation and really start the migration.
+                     */
+                    qdev->pending_deleted_event = false;
+                } else {
+                    hotplug_ctrl = qdev_get_hotplug_handler(qdev);
+                    hotplug_handler_unplug(hotplug_ctrl, qdev, &error_abort);
+                    object_unparent(OBJECT(qdev));
+                }
             }
         }
     }
@@ -396,6 +414,12 @@ void acpi_pcihp_device_unplug_request_cb(HotplugHandler *hotplug_dev,
         return;
     }
 
+    /*
+     * pending_deleted_event is used by virtio-net failover to detect the
+     * end of the unplug operation, the flag is set to false in
+     * acpi_pcihp_eject_slot() when the operation is completed.
+     */
+    pdev->qdev.pending_deleted_event = true;
     s->acpi_pcihp_pci_status[bsel].down |= (1U << slot);
     acpi_send_event(DEVICE(hotplug_dev), ACPI_PCI_HOTPLUG_STATUS);
 }
-- 
2.33.1

[PATCH v5 4/4] tests/libqtest: update virtio-net failover test

[Laurent Vivier]

Update the migration test to check we correctly wait the end
of the card unplug before doing the migration.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
 tests/qtest/virtio-net-failover.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tests/qtest/virtio-net-failover.c b/tests/qtest/virtio-net-failover.c
index 11fa0b21f8bf..9a81133154d6 100644
--- a/tests/qtest/virtio-net-failover.c
+++ b/tests/qtest/virtio-net-failover.c
@@ -541,6 +541,29 @@ static void test_outmigrate(gconstpointer opaque)
 
     qobject_unref(resp);
 
+    /* wait the end of the migration setup phase */
+    while (true) {
+        const gchar *status;
+
+        ret = migrate_status(qts);
+
+        status = qdict_get_str(ret, "status");
+        if (strcmp(status, "wait-unplug") == 0) {
+            break;
+        }
+
+        /* The migration must not start if the card is not ejected */
+        g_assert_cmpstr(status, !=, "active");
+        g_assert_cmpstr(status, !=, "completed");
+        g_assert_cmpstr(status, !=, "failed");
+        g_assert_cmpstr(status, !=, "cancelling");
+        g_assert_cmpstr(status, !=, "cancelled");
+
+        qobject_unref(ret);
+    }
+    qobject_unref(ret);
+
+    /* OS unplugs the cards, QEMU can move from wait-unplug state */
     qtest_outl(qts, ACPI_PCIHP_ADDR_ICH9 + PCI_EJ_BASE, 1);
 
     qtest_qmp_eventwait(qts, "STOP");
-- 
2.33.1

Re: [PATCH v5 0/4] tests/qtest: add some tests for virtio-net failover

[Michael S. Tsirkin]

On Fri, Nov 19, 2021 at 10:07:14AM +0100, Laurent Vivier wrote:
> This series adds a qtest entry to test virtio-net failover feature.

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>


> We check following error cases:
> 
> - check missing id on device with failover_pair_id triggers an error
> - check a primary device plugged on a bus that doesn't support hotplug
>   triggers an error
> 
> We check the status of the machine before and after hotplugging cards and
> feature negotiation:
> 
> - check we don't see the primary device at boot if failover is on
> - check we see the primary device at boot if failover is off
> - check we don't see the primary device if failover is on
>   but failover_pair_id is not the one with on (I think this should be changed)
> - check the primary device is plugged after the feature negotiation
> - check the result if the primary device is plugged before standby device and
>   vice-versa
> - check the if the primary device is coldplugged and the standy device
>   hotplugged and vice-versa
> - check the migration triggers the unplug and the hotplug
> 
> There is one preliminary patch in the series:
> 
> - PATCH 1 introduces a function to enable PCI bridge.
>   Failover needs to be plugged on a pcie-root-port and while
>   the root port is not configured the cards behind it are not
>   available
> 
> v5:
> - re-add the wait-unplug test that has been removed from v4 by mistake.
> 
> v4:
> - rely on query-migrate status to know the migration state rather than
>   to wait the STOP event.
> - remove the patch to add time out to qtest_qmp_eventwait()
> 
> v3:
> - fix a bug with ACPI unplug and add the related test
> 
> v2:
> - remove PATCH 1 that introduced a function that can be replaced by
>   qobject_to_json_pretty() (Markus)
> - Add migration to a file and from the file to check the card is
>   correctly unplugged on the source, and hotplugged on the dest
> - Add an ACPI call to eject the card as the kernel would do
> 
> Laurent Vivier (4):
>   qtest/libqos: add a function to initialize secondary PCI buses
>   tests/qtest: add some tests for virtio-net failover
>   failover: fix unplug pending detection
>   tests/libqtest: update virtio-net failover test
> 
>  hw/acpi/pcihp.c                   |  30 +-
>  include/hw/pci/pci_bridge.h       |   8 +
>  tests/qtest/libqos/pci.c          | 118 ++++++
>  tests/qtest/libqos/pci.h          |   1 +
>  tests/qtest/meson.build           |   3 +
>  tests/qtest/virtio-net-failover.c | 681 ++++++++++++++++++++++++++++++
>  6 files changed, 838 insertions(+), 3 deletions(-)
>  create mode 100644 tests/qtest/virtio-net-failover.c
> 
> -- 
> 2.33.1
> 

Re: [PATCH v5 3/4] failover: fix unplug pending detection

[Michael S. Tsirkin]

On Fri, Nov 19, 2021 at 10:07:17AM +0100, Laurent Vivier wrote:
> Failover needs to detect the end of the PCI unplug to start migration
> after the VFIO card has been unplugged.
> 
> To do that, a flag is set in pcie_cap_slot_unplug_request_cb() and reset in
> pcie_unplug_device().
> 
> But since
>     17858a169508 ("hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35")
> we have switched to ACPI unplug and these functions are not called anymore
> and the flag not set. So failover migration is not able to detect if card
> is really unplugged and acts as it's done as soon as it's started. So it
> doesn't wait the end of the unplug to start the migration. We don't see any
> problem when we test that because ACPI unplug is faster than PCIe native
> hotplug and when the migration really starts the unplug operation is
> already done.
> 
> See c000a9bd06ea ("pci: mark device having guest unplug request pending")
>     a99c4da9fc2a ("pci: mark devices partially unplugged")
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Reviewed-by: Ani Sinha <ani@anisinha.ca>

Hmm.  I think this one may be needed for this release actually.
Isolate from testing changes and repost?

> ---
>  hw/acpi/pcihp.c | 30 +++++++++++++++++++++++++++---
>  1 file changed, 27 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> index f610a25d2ef9..30405b5113d7 100644
> --- a/hw/acpi/pcihp.c
> +++ b/hw/acpi/pcihp.c
> @@ -222,9 +222,27 @@ static void acpi_pcihp_eject_slot(AcpiPciHpState *s, unsigned bsel, unsigned slo
>          PCIDevice *dev = PCI_DEVICE(qdev);
>          if (PCI_SLOT(dev->devfn) == slot) {
>              if (!acpi_pcihp_pc_no_hotplug(s, dev)) {
> -                hotplug_ctrl = qdev_get_hotplug_handler(qdev);
> -                hotplug_handler_unplug(hotplug_ctrl, qdev, &error_abort);
> -                object_unparent(OBJECT(qdev));
> +                /*
> +                 * partially_hotplugged is used by virtio-net failover:
> +                 * failover has asked the guest OS to unplug the device
> +                 * but we need to keep some references to the device
> +                 * to be able to plug it back in case of failure so
> +                 * we don't execute hotplug_handler_unplug().
> +                 */
> +                if (dev->partially_hotplugged) {
> +                    /*
> +                     * pending_deleted_event is set to true when
> +                     * virtio-net failover asks to unplug the device,
> +                     * and set to false here when the operation is done
> +                     * This is used by the migration loop to detect the
> +                     * end of the operation and really start the migration.
> +                     */
> +                    qdev->pending_deleted_event = false;
> +                } else {
> +                    hotplug_ctrl = qdev_get_hotplug_handler(qdev);
> +                    hotplug_handler_unplug(hotplug_ctrl, qdev, &error_abort);
> +                    object_unparent(OBJECT(qdev));
> +                }
>              }
>          }
>      }
> @@ -396,6 +414,12 @@ void acpi_pcihp_device_unplug_request_cb(HotplugHandler *hotplug_dev,
>          return;
>      }
>  
> +    /*
> +     * pending_deleted_event is used by virtio-net failover to detect the
> +     * end of the unplug operation, the flag is set to false in
> +     * acpi_pcihp_eject_slot() when the operation is completed.
> +     */
> +    pdev->qdev.pending_deleted_event = true;
>      s->acpi_pcihp_pci_status[bsel].down |= (1U << slot);
>      acpi_send_event(DEVICE(hotplug_dev), ACPI_PCI_HOTPLUG_STATUS);
>  }
> -- 
> 2.33.1

Re: [PATCH v5 3/4] failover: fix unplug pending detection

[Thomas Huth]

On 08/12/2021 08.36, Michael S. Tsirkin wrote:
> On Fri, Nov 19, 2021 at 10:07:17AM +0100, Laurent Vivier wrote:
>> Failover needs to detect the end of the PCI unplug to start migration
>> after the VFIO card has been unplugged.
>>
>> To do that, a flag is set in pcie_cap_slot_unplug_request_cb() and reset in
>> pcie_unplug_device().
>>
>> But since
>>      17858a169508 ("hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35")
>> we have switched to ACPI unplug and these functions are not called anymore
>> and the flag not set. So failover migration is not able to detect if card
>> is really unplugged and acts as it's done as soon as it's started. So it
>> doesn't wait the end of the unplug to start the migration. We don't see any
>> problem when we test that because ACPI unplug is faster than PCIe native
>> hotplug and when the migration really starts the unplug operation is
>> already done.
>>
>> See c000a9bd06ea ("pci: mark device having guest unplug request pending")
>>      a99c4da9fc2a ("pci: mark devices partially unplugged")
>>
>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>> Reviewed-by: Ani Sinha <ani@anisinha.ca>
> 
> Hmm.  I think this one may be needed for this release actually.
> Isolate from testing changes and repost?

You merged it already here:

  https://gitlab.com/qemu-project/qemu/-/commit/9323f892b39d133eb6

so we should be fine :-)

  Thomas

Re: [PATCH v5 3/4] failover: fix unplug pending detection

[Ani Sinha]

On Wed, Dec 8, 2021 at 1:20 PM Thomas Huth <thuth@redhat.com> wrote:
>
> On 08/12/2021 08.36, Michael S. Tsirkin wrote:
> > On Fri, Nov 19, 2021 at 10:07:17AM +0100, Laurent Vivier wrote:
> >> Failover needs to detect the end of the PCI unplug to start migration
> >> after the VFIO card has been unplugged.
> >>
> >> To do that, a flag is set in pcie_cap_slot_unplug_request_cb() and reset in
> >> pcie_unplug_device().
> >>
> >> But since
> >>      17858a169508 ("hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35")
> >> we have switched to ACPI unplug and these functions are not called anymore
> >> and the flag not set. So failover migration is not able to detect if card
> >> is really unplugged and acts as it's done as soon as it's started. So it
> >> doesn't wait the end of the unplug to start the migration. We don't see any
> >> problem when we test that because ACPI unplug is faster than PCIe native
> >> hotplug and when the migration really starts the unplug operation is
> >> already done.
> >>
> >> See c000a9bd06ea ("pci: mark device having guest unplug request pending")
> >>      a99c4da9fc2a ("pci: mark devices partially unplugged")
> >>
> >> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> >> Reviewed-by: Ani Sinha <ani@anisinha.ca>
> >
> > Hmm.  I think this one may be needed for this release actually.
> > Isolate from testing changes and repost?
>
> You merged it already here:
>
>   https://gitlab.com/qemu-project/qemu/-/commit/9323f892b39d133eb6

Yes I pointed this out in the other thread. Michael was not CC'd there
somehow ...

>
> so we should be fine :-)
>
>   Thomas
>

Re: [PATCH v5 3/4] failover: fix unplug pending detection

[Michael S. Tsirkin]

On Wed, Dec 08, 2021 at 08:50:34AM +0100, Thomas Huth wrote:
> On 08/12/2021 08.36, Michael S. Tsirkin wrote:
> > On Fri, Nov 19, 2021 at 10:07:17AM +0100, Laurent Vivier wrote:
> > > Failover needs to detect the end of the PCI unplug to start migration
> > > after the VFIO card has been unplugged.
> > > 
> > > To do that, a flag is set in pcie_cap_slot_unplug_request_cb() and reset in
> > > pcie_unplug_device().
> > > 
> > > But since
> > >      17858a169508 ("hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35")
> > > we have switched to ACPI unplug and these functions are not called anymore
> > > and the flag not set. So failover migration is not able to detect if card
> > > is really unplugged and acts as it's done as soon as it's started. So it
> > > doesn't wait the end of the unplug to start the migration. We don't see any
> > > problem when we test that because ACPI unplug is faster than PCIe native
> > > hotplug and when the migration really starts the unplug operation is
> > > already done.
> > > 
> > > See c000a9bd06ea ("pci: mark device having guest unplug request pending")
> > >      a99c4da9fc2a ("pci: mark devices partially unplugged")
> > > 
> > > Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> > > Reviewed-by: Ani Sinha <ani@anisinha.ca>
> > 
> > Hmm.  I think this one may be needed for this release actually.
> > Isolate from testing changes and repost?
> 
> You merged it already here:
> 
>  https://gitlab.com/qemu-project/qemu/-/commit/9323f892b39d133eb6

Oh, good. Forgot to drop the tag.

> so we should be fine :-)
> 
>  Thomas