Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

virtio,pc,pci: features, cleanups, fixes

misc fixes, cleanups

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

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# gpg: Signature made Sat 02 Dec 2023 15:57:00 EST
# gpg:                using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg:                issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
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#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu:
  vhost-user-scsi: free the inflight area when reset
  vhost-user: fix the reconnect error
  msix: unset PCIDevice::msix_vector_poll_notifier in rollback
  virtio-iommu: Remove useless !sdev check in virtio_iommu_probe()
  hw/i386: fix short-circuit logic with non-optimizing builds
  hw/acpi/erst: Do not ignore Error* in realize handler
  pcie_sriov: Remove g_new assertion
  virtio-sound: add realize() error cleanup path
  virtio-snd: check AUD_register_card return value
  hw/audio/hda-codec: reenable the audio mixer
  hw/audio/hda-codec: fix multiplication overflow
  hw/audio/virtio-snd-pci: fix the PCI class code
  tests/acpi/bios-tables-test: do not write new blobs unless there are changes
  netdev: set timeout depending on loadavg
  osdep: add getloadavg

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

16 files changed, 152 insertions, 49 deletions

diff --git a/hw/acpi/erst.c b/hw/acpi/erst.c
index 35007d8017..ba751dc60e 100644
--- a/hw/acpi/erst.c
+++ b/hw/acpi/erst.c
@@ -947,6 +947,7 @@ static const VMStateDescription erst_vmstate  = {
 
 static void erst_realizefn(PCIDevice *pci_dev, Error **errp)
 {
+    ERRP_GUARD();
     ERSTDeviceState *s = ACPIERST(pci_dev);
 
     trace_acpi_erst_realizefn_in();
@@ -964,9 +965,15 @@ static void erst_realizefn(PCIDevice *pci_dev, Error **errp)
 
     /* HostMemoryBackend size will be multiple of PAGE_SIZE */
     s->storage_size = object_property_get_int(OBJECT(s->hostmem), "size", errp);
+    if (*errp) {
+        return;
+    }
 
     /* Initialize backend storage and record_count */
     check_erst_backend_storage(s, errp);
+    if (*errp) {
+        return;
+    }
 
     /* BAR 0: Programming registers */
     memory_region_init_io(&s->iomem_mr, OBJECT(pci_dev), &erst_reg_ops, s,
@@ -977,6 +984,9 @@ static void erst_realizefn(PCIDevice *pci_dev, Error **errp)
     memory_region_init_ram(&s->exchange_mr, OBJECT(pci_dev),
                             "erst.exchange",
                             le32_to_cpu(s->header->record_size), errp);
+    if (*errp) {
+        return;
+    }
     pci_register_bar(pci_dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY,
                         &s->exchange_mr);
 
diff --git a/hw/audio/hda-codec.c b/hw/audio/hda-codec.c
index b9ad1f4c39..0bc20d49f6 100644
--- a/hw/audio/hda-codec.c
+++ b/hw/audio/hda-codec.c
@@ -22,6 +22,7 @@
 #include "hw/qdev-properties.h"
 #include "intel-hda.h"
 #include "migration/vmstate.h"
+#include "qemu/host-utils.h"
 #include "qemu/module.h"
 #include "intel-hda-defs.h"
 #include "audio/audio.h"
@@ -189,9 +190,9 @@ struct HDAAudioState {
     bool     use_timer;
 };
 
-static inline int64_t hda_bytes_per_second(HDAAudioStream *st)
+static inline uint32_t hda_bytes_per_second(HDAAudioStream *st)
 {
-    return 2LL * st->as.nchannels * st->as.freq;
+    return 2 * (uint32_t)st->as.nchannels * (uint32_t)st->as.freq;
 }
 
 static inline void hda_timer_sync_adjust(HDAAudioStream *st, int64_t target_pos)
@@ -222,12 +223,18 @@ static void hda_audio_input_timer(void *opaque)
 
     int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 
-    int64_t buft_start = st->buft_start;
+    int64_t uptime = now - st->buft_start;
     int64_t wpos = st->wpos;
     int64_t rpos = st->rpos;
+    int64_t wanted_rpos;
 
-    int64_t wanted_rpos = hda_bytes_per_second(st) * (now - buft_start)
-                          / NANOSECONDS_PER_SECOND;
+    if (uptime <= 0) {
+        /* wanted_rpos <= 0 */
+        goto out_timer;
+    }
+
+    wanted_rpos = muldiv64(uptime, hda_bytes_per_second(st),
+                           NANOSECONDS_PER_SECOND);
     wanted_rpos &= -4; /* IMPORTANT! clip to frames */
 
     if (wanted_rpos <= rpos) {
@@ -286,12 +293,18 @@ static void hda_audio_output_timer(void *opaque)
 
     int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 
-    int64_t buft_start = st->buft_start;
+    int64_t uptime = now - st->buft_start;
     int64_t wpos = st->wpos;
     int64_t rpos = st->rpos;
+    int64_t wanted_wpos;
+
+    if (uptime <= 0) {
+        /* wanted_wpos <= 0 */
+        goto out_timer;
+    }
 
-    int64_t wanted_wpos = hda_bytes_per_second(st) * (now - buft_start)
-                          / NANOSECONDS_PER_SECOND;
+    wanted_wpos = muldiv64(uptime, hda_bytes_per_second(st),
+                           NANOSECONDS_PER_SECOND);
     wanted_wpos &= -4; /* IMPORTANT! clip to frames */
 
     if (wanted_wpos <= wpos) {
@@ -855,10 +868,10 @@ static Property hda_audio_properties[] = {
 static void hda_audio_init_output(HDACodecDevice *hda, Error **errp)
 {
     HDAAudioState *a = HDA_AUDIO(hda);
-    const struct desc_codec *desc = &output_nomixemu;
+    const struct desc_codec *desc = &output_mixemu;
 
     if (!a->mixer) {
-        desc = &output_mixemu;
+        desc = &output_nomixemu;
     }
 
     hda_audio_init(hda, desc, errp);
@@ -867,10 +880,10 @@ static void hda_audio_init_output(HDACodecDevice *hda, Error **errp)
 static void hda_audio_init_duplex(HDACodecDevice *hda, Error **errp)
 {
     HDAAudioState *a = HDA_AUDIO(hda);
-    const struct desc_codec *desc = &duplex_nomixemu;
+    const struct desc_codec *desc = &duplex_mixemu;
 
     if (!a->mixer) {
-        desc = &duplex_mixemu;
+        desc = &duplex_nomixemu;
     }
 
     hda_audio_init(hda, desc, errp);
@@ -879,10 +892,10 @@ static void hda_audio_init_duplex(HDACodecDevice *hda, Error **errp)
 static void hda_audio_init_micro(HDACodecDevice *hda, Error **errp)
 {
     HDAAudioState *a = HDA_AUDIO(hda);
-    const struct desc_codec *desc = &micro_nomixemu;
+    const struct desc_codec *desc = &micro_mixemu;
 
     if (!a->mixer) {
-        desc = &micro_mixemu;
+        desc = &micro_nomixemu;
     }
 
     hda_audio_init(hda, desc, errp);
diff --git a/hw/audio/virtio-snd-pci.c b/hw/audio/virtio-snd-pci.c
index 0f92e0752b..ab58c6410e 100644
--- a/hw/audio/virtio-snd-pci.c
+++ b/hw/audio/virtio-snd-pci.c
@@ -47,12 +47,14 @@ static void virtio_snd_pci_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
     VirtioPCIClass *vpciklass = VIRTIO_PCI_CLASS(klass);
+    PCIDeviceClass *pcidevklass = PCI_DEVICE_CLASS(klass);
 
     device_class_set_props(dc, virtio_snd_pci_properties);
     dc->desc = "Virtio Sound";
     set_bit(DEVICE_CATEGORY_SOUND, dc->categories);
 
     vpciklass->realize = virtio_snd_pci_realize;
+    pcidevklass->class_id = PCI_CLASS_MULTIMEDIA_AUDIO;
 }
 
 static void virtio_snd_pci_instance_init(Object *obj)
diff --git a/hw/audio/virtio-snd.c b/hw/audio/virtio-snd.c
index 2fe966e311..3c9f94e94a 100644
--- a/hw/audio/virtio-snd.c
+++ b/hw/audio/virtio-snd.c
@@ -36,6 +36,7 @@ static void virtio_snd_pcm_out_cb(void *data, int available);
 static void virtio_snd_process_cmdq(VirtIOSound *s);
 static void virtio_snd_pcm_flush(VirtIOSoundPCMStream *stream);
 static void virtio_snd_pcm_in_cb(void *data, int available);
+static void virtio_snd_unrealize(DeviceState *dev);
 
 static uint32_t supported_formats = BIT(VIRTIO_SND_PCM_FMT_S8)
                                   | BIT(VIRTIO_SND_PCM_FMT_U8)
@@ -1065,23 +1066,9 @@ static void virtio_snd_realize(DeviceState *dev, Error **errp)
     virtio_snd_pcm_set_params default_params = { 0 };
     uint32_t status;
 
-    vsnd->pcm = NULL;
-    vsnd->vmstate =
-        qemu_add_vm_change_state_handler(virtio_snd_vm_state_change, vsnd);
-
     trace_virtio_snd_realize(vsnd);
 
-    vsnd->pcm = g_new0(VirtIOSoundPCM, 1);
-    vsnd->pcm->snd = vsnd;
-    vsnd->pcm->streams =
-        g_new0(VirtIOSoundPCMStream *, vsnd->snd_conf.streams);
-    vsnd->pcm->pcm_params =
-        g_new0(virtio_snd_pcm_set_params, vsnd->snd_conf.streams);
-
-    virtio_init(vdev, VIRTIO_ID_SOUND, sizeof(virtio_snd_config));
-    virtio_add_feature(&vsnd->features, VIRTIO_F_VERSION_1);
-
-    /* set number of jacks and streams */
+    /* check number of jacks and streams */
     if (vsnd->snd_conf.jacks > 8) {
         error_setg(errp,
                    "Invalid number of jacks: %"PRIu32,
@@ -1102,7 +1089,22 @@ static void virtio_snd_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    AUD_register_card("virtio-sound", &vsnd->card, errp);
+    if (!AUD_register_card("virtio-sound", &vsnd->card, errp)) {
+        return;
+    }
+
+    vsnd->vmstate =
+        qemu_add_vm_change_state_handler(virtio_snd_vm_state_change, vsnd);
+
+    vsnd->pcm = g_new0(VirtIOSoundPCM, 1);
+    vsnd->pcm->snd = vsnd;
+    vsnd->pcm->streams =
+        g_new0(VirtIOSoundPCMStream *, vsnd->snd_conf.streams);
+    vsnd->pcm->pcm_params =
+        g_new0(virtio_snd_pcm_set_params, vsnd->snd_conf.streams);
+
+    virtio_init(vdev, VIRTIO_ID_SOUND, sizeof(virtio_snd_config));
+    virtio_add_feature(&vsnd->features, VIRTIO_F_VERSION_1);
 
     /* set default params for all streams */
     default_params.features = 0;
@@ -1128,16 +1130,21 @@ static void virtio_snd_realize(DeviceState *dev, Error **errp)
             error_setg(errp,
                        "Can't initialize stream params, device responded with %s.",
                        print_code(status));
-            return;
+            goto error_cleanup;
         }
         status = virtio_snd_pcm_prepare(vsnd, i);
         if (status != cpu_to_le32(VIRTIO_SND_S_OK)) {
             error_setg(errp,
                        "Can't prepare streams, device responded with %s.",
                        print_code(status));
-            return;
+            goto error_cleanup;
         }
     }
+
+    return;
+
+error_cleanup:
+    virtio_snd_unrealize(dev);
 }
 
 static inline void return_tx_buffer(VirtIOSoundPCMStream *stream,
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 818b833108..2863d80d15 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -326,7 +326,6 @@ static int vhost_user_blk_connect(DeviceState *dev, Error **errp)
     if (s->connected) {
         return 0;
     }
-    s->connected = true;
 
     s->dev.num_queues = s->num_queues;
     s->dev.nvqs = s->num_queues;
@@ -343,15 +342,14 @@ static int vhost_user_blk_connect(DeviceState *dev, Error **errp)
         return ret;
     }
 
+    s->connected = true;
+
     /* restore vhost state */
     if (virtio_device_started(vdev, vdev->status)) {
         ret = vhost_user_blk_start(vdev, errp);
-        if (ret < 0) {
-            return ret;
-        }
     }
 
-    return 0;
+    return ret;
 }
 
 static void vhost_user_blk_disconnect(DeviceState *dev)
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index b3d054889b..2b6291ad8d 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -131,8 +131,12 @@ void x86_cpus_init(X86MachineState *x86ms, int default_cpu_version)
     /*
      * Can we support APIC ID 255 or higher?  With KVM, that requires
      * both in-kernel lapic and X2APIC userspace API.
+     *
+     * kvm_enabled() must go first to ensure that kvm_* references are
+     * not emitted for the linker to consume (kvm_enabled() is
+     * a literal `0` in configurations where kvm_* aren't defined)
      */
-    if (x86ms->apic_id_limit > 255 && kvm_enabled() &&
+    if (kvm_enabled() && x86ms->apic_id_limit > 255 &&
         (!kvm_irqchip_in_kernel() || !kvm_enable_x2apic())) {
         error_report("current -smp configuration requires kernel "
                      "irqchip and X2APIC API support.");
@@ -418,8 +422,13 @@ void x86_cpu_pre_plug(HotplugHandler *hotplug_dev,
     }
     cpu->thread_id = topo_ids.smt_id;
 
-    if (hyperv_feat_enabled(cpu, HYPERV_FEAT_VPINDEX) &&
-        kvm_enabled() && !kvm_hv_vpindex_settable()) {
+    /*
+    * kvm_enabled() must go first to ensure that kvm_* references are
+    * not emitted for the linker to consume (kvm_enabled() is
+    * a literal `0` in configurations where kvm_* aren't defined)
+    */
+    if (kvm_enabled() && hyperv_feat_enabled(cpu, HYPERV_FEAT_VPINDEX) &&
+        !kvm_hv_vpindex_settable()) {
         error_setg(errp, "kernel doesn't allow setting HyperV VP_INDEX");
         return;
     }
diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index ab8869d9d0..cd817f4ca8 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -648,6 +648,7 @@ undo:
     }
     dev->msix_vector_use_notifier = NULL;
     dev->msix_vector_release_notifier = NULL;
+    dev->msix_vector_poll_notifier = NULL;
     return ret;
 }
 
diff --git a/hw/pci/pcie_sriov.c b/hw/pci/pcie_sriov.c
index 5ef8950940..a1fe65f5d8 100644
--- a/hw/pci/pcie_sriov.c
+++ b/hw/pci/pcie_sriov.c
@@ -178,7 +178,6 @@ static void register_vfs(PCIDevice *dev)
     num_vfs = pci_get_word(dev->config + sriov_cap + PCI_SRIOV_NUM_VF);
 
     dev->exp.sriov_pf.vf = g_new(PCIDevice *, num_vfs);
-    assert(dev->exp.sriov_pf.vf);
 
     trace_sriov_register_vfs(dev->name, PCI_SLOT(dev->devfn),
                              PCI_FUNC(dev->devfn), num_vfs);
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index 4486500cac..780f10559d 100644
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -147,7 +147,6 @@ static int vhost_user_scsi_connect(DeviceState *dev, Error **errp)
     if (s->connected) {
         return 0;
     }
-    s->connected = true;
 
     vsc->dev.num_queues = vs->conf.num_queues;
     vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
@@ -161,6 +160,8 @@ static int vhost_user_scsi_connect(DeviceState *dev, Error **errp)
         return ret;
     }
 
+    s->connected = true;
+
     /* restore vhost state */
     if (virtio_device_started(vdev, vdev->status)) {
         ret = vhost_user_scsi_start(s, errp);
@@ -359,6 +360,20 @@ static Property vhost_user_scsi_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+static void vhost_user_scsi_reset(VirtIODevice *vdev)
+{
+    VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
+    VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
+
+    vhost_dev_free_inflight(vsc->inflight);
+}
+
+static struct vhost_dev *vhost_user_scsi_get_vhost(VirtIODevice *vdev)
+{
+    VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
+    return &vsc->dev;
+}
+
 static const VMStateDescription vmstate_vhost_scsi = {
     .name = "virtio-scsi",
     .minimum_version_id = 1,
@@ -384,6 +399,8 @@ static void vhost_user_scsi_class_init(ObjectClass *klass, void *data)
     vdc->set_config = vhost_scsi_common_set_config;
     vdc->set_status = vhost_user_scsi_set_status;
     fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
+    vdc->reset = vhost_user_scsi_reset;
+    vdc->get_vhost = vhost_user_scsi_get_vhost;
 }
 
 static void vhost_user_scsi_instance_init(Object *obj)
diff --git a/hw/virtio/vhost-user-gpio.c b/hw/virtio/vhost-user-gpio.c
index aff2d7eff6..a83437a5da 100644
--- a/hw/virtio/vhost-user-gpio.c
+++ b/hw/virtio/vhost-user-gpio.c
@@ -229,7 +229,6 @@ static int vu_gpio_connect(DeviceState *dev, Error **errp)
     if (gpio->connected) {
         return 0;
     }
-    gpio->connected = true;
 
     vhost_dev_set_config_notifier(vhost_dev, &gpio_ops);
     gpio->vhost_user.supports_config = true;
@@ -243,6 +242,8 @@ static int vu_gpio_connect(DeviceState *dev, Error **errp)
         return ret;
     }
 
+    gpio->connected = true;
+
     /* restore vhost state */
     if (virtio_device_started(vdev, vdev->status)) {
         vu_gpio_start(vdev);
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 89fb5767d1..9d463efc52 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -698,9 +698,6 @@ static int virtio_iommu_probe(VirtIOIOMMU *s,
     }
 
     sdev = container_of(iommu_mr, IOMMUDevice, iommu_mr);
-    if (!sdev) {
-        return -EINVAL;
-    }
 
     count = virtio_iommu_fill_resv_mem_prop(sdev, ep_id, buf, free);
     if (count < 0) {
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index e5105571cf..3a160f86ed 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -2137,7 +2137,7 @@ void virtio_reset(void *opaque)
         vdev->device_endian = virtio_default_endian();
     }
 
-    if (vdev->vhost_started) {
+    if (vdev->vhost_started && k->get_vhost) {
         vhost_reset_device(k->get_vhost(vdev));
     }
 
diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index 475a1c62ff..d30ba73eda 100644
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -779,6 +779,16 @@ static inline int platform_does_not_support_system(const char *command)
 }
 #endif /* !HAVE_SYSTEM_FUNCTION */
 
+/**
+ * If the load average was unobtainable, -1 is returned
+ */
+#ifndef HAVE_GETLOADAVG_FUNCTION
+static inline int getloadavg(double loadavg[], int nelem)
+{
+    return -1;
+}
+#endif /* !HAVE_GETLOADAVG_FUNCTION */
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/meson.build b/meson.build
index ec01f8b138..d2c4c2adb3 100644
--- a/meson.build
+++ b/meson.build
@@ -2293,6 +2293,7 @@ config_host_data.set('HAVE_GLIB_WITH_SLICE_ALLOCATOR', glib_has_gslice)
 config_host_data.set('HAVE_OPENPTY', cc.has_function('openpty', dependencies: util))
 config_host_data.set('HAVE_STRCHRNUL', cc.has_function('strchrnul'))
 config_host_data.set('HAVE_SYSTEM_FUNCTION', cc.has_function('system', prefix: '#include <stdlib.h>'))
+config_host_data.set('HAVE_GETLOADAVG_FUNCTION', cc.has_function('getloadavg', prefix: '#include <stdlib.h>'))
 if rbd.found()
   config_host_data.set('HAVE_RBD_NAMESPACE_EXISTS',
                        cc.has_function('rbd_namespace_exists',
diff --git a/tests/qtest/bios-tables-test.c b/tests/qtest/bios-tables-test.c
index 71af5cf69f..fe6a9a8563 100644
--- a/tests/qtest/bios-tables-test.c
+++ b/tests/qtest/bios-tables-test.c
@@ -112,6 +112,7 @@ static const char *iasl;
 #endif
 
 static int verbosity_level;
+static GArray *load_expected_aml(test_data *data);
 
 static bool compare_signature(const AcpiSdtTable *sdt, const char *signature)
 {
@@ -244,21 +245,32 @@ static void test_acpi_fadt_table(test_data *data)
 
 static void dump_aml_files(test_data *data, bool rebuild)
 {
-    AcpiSdtTable *sdt;
+    AcpiSdtTable *sdt, *exp_sdt;
     GError *error = NULL;
     gchar *aml_file = NULL;
+    test_data exp_data = {};
     gint fd;
     ssize_t ret;
     int i;
 
+    exp_data.tables = load_expected_aml(data);
     for (i = 0; i < data->tables->len; ++i) {
         const char *ext = data->variant ? data->variant : "";
         sdt = &g_array_index(data->tables, AcpiSdtTable, i);
+        exp_sdt = &g_array_index(exp_data.tables, AcpiSdtTable, i);
         g_assert(sdt->aml);
+        g_assert(exp_sdt->aml);
 
         if (rebuild) {
             aml_file = g_strdup_printf("%s/%s/%.4s%s", data_dir, data->machine,
                                        sdt->aml, ext);
+            if (!g_file_test(aml_file, G_FILE_TEST_EXISTS) &&
+                sdt->aml_len == exp_sdt->aml_len &&
+                !memcmp(sdt->aml, exp_sdt->aml, sdt->aml_len)) {
+                /* identical tables, no need to write new files */
+                g_free(aml_file);
+                continue;
+            }
             fd = g_open(aml_file, O_WRONLY|O_TRUNC|O_CREAT,
                         S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH);
             if (fd < 0) {
diff --git a/tests/qtest/netdev-socket.c b/tests/qtest/netdev-socket.c
index 7ba1eff120..bb99d08b5e 100644
--- a/tests/qtest/netdev-socket.c
+++ b/tests/qtest/netdev-socket.c
@@ -18,6 +18,32 @@
 
 #define CONNECTION_TIMEOUT    120
 
+static double connection_timeout(void)
+{
+    double load;
+    int ret = getloadavg(&load, 1);
+
+    /*
+     * If we can't get load data, or load is low because we just started
+     * running, assume load of 1 (we are alone in this system).
+     */
+    if (ret < 1 || load < 1.0) {
+        load = 1.0;
+    }
+    /*
+     * No one wants to wait more than 10 minutes for this test. Higher load?
+     * Too bad.
+     */
+    if (load > 10.0) {
+        fprintf(stderr, "Warning: load %f higher than 10 - test might timeout\n",
+                load);
+        load = 10.0;
+    }
+
+    /* if load is high increase timeout as we might not get a chance to run */
+    return load * CONNECTION_TIMEOUT;
+}
+
 #define EXPECT_STATE(q, e, t)                             \
 do {                                                      \
     char *resp = NULL;                                    \
@@ -31,7 +57,7 @@ do {                                                      \
         if (g_str_equal(resp, e)) {                       \
             break;                                        \
         }                                                 \
-    } while (g_test_timer_elapsed() < CONNECTION_TIMEOUT); \
+    } while (g_test_timer_elapsed() < connection_timeout()); \
     g_assert_cmpstr(resp, ==, e);                         \
     g_free(resp);                                         \
 } while (0)