Commit graph

8 commits

Author SHA1 Message Date
Haoqian He
bc85aae420 vhost-user: return failure if backend crash when live migration
Live migration should be terminated if the vhost-user backend crashes
before the migration completes.

Specifically, since the vhost device will be stopped when VM is stopped
before the end of the live migration, in current implementation if the
backend crashes, vhost-user device set_status() won't return failure,
live migration won't perceive the disconnection between QEMU and the
backend.

When the VM is migrated to the destination, the inflight IO will be
resubmitted, and if the IO was completed out of order before, it will
cause IO error.

To fix this issue:
1. Add the return value to set_status() for VirtioDeviceClass.
  a. For the vhost-user device, return failure when the backend crashes.
  b. For other virtio devices, always return 0.
2. Return failure if vhost_dev_stop() failed for vhost-user device.

If QEMU loses connection with the vhost-user backend, virtio set_status()
can return failure to the upper layer, migration_completion() can handle
the error, terminate the live migration, and restore the VM, so that
inflight IO can be completed normally.

Signed-off-by: Haoqian He <haoqian.he@smartx.com>
Message-Id: <20250416024729.3289157-4-haoqian.he@smartx.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-05-14 05:39:15 -04:00
Philippe Mathieu-Daudé
12d1a768bd qom: Have class_init() take a const data argument
Mechanical change using gsed, then style manually adapted
to pass checkpatch.pl script.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250424194905.82506-4-philmd@linaro.org>
2025-04-25 17:00:41 +02:00
Markus Armbruster
8a2b516ba2 cleanup: Drop pointless return at end of function
A few functions now end with a label.  The next commit will clean them
up.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250407082643.2310002-3-armbru@redhat.com>
[Straightforward conflict with commit 988ad4cceb (hw/loongarch/virt:
Fix cpuslot::cpu set at last in virt_cpu_plug()) resolved]
2025-04-24 09:33:42 +02:00
Richard Henderson
5fcabe628b include/hw/qdev-properties: Remove DEFINE_PROP_END_OF_LIST
Now that all of the Property arrays are counted, we can remove
the terminator object from each array.  Update the assertions
in device_class_set_props to match.

With struct Property being 88 bytes, this was a rather large
form of terminator.  Saves 30k from qemu-system-aarch64.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Link: https://lore.kernel.org/r/20241218134251.4724-21-richard.henderson@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-12-19 19:36:37 +01:00
Richard Henderson
1577a9180f hw/virtio: Constify all Property
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-12-15 12:56:40 -06:00
Philippe Mathieu-Daudé
ee1004bba6 bulk: Access existing variables initialized to &S->F when available
When a variable is initialized to &struct->field, use it
in place. Rationale: while this makes the code more concise,
this also helps static analyzers.

Mechanical change using the following Coccinelle spatch script:

 @@
 type S, F;
 identifier s, m, v;
 @@
      S *s;
      ...
      F *v = &s->m;
      <+...
 -    &s->m
 +    v
      ...+>

Inspired-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240129164514.73104-2-philmd@linaro.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
[thuth: Dropped hunks that need a rebase, and fixed sizeof() in pmu_realize()]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-03-12 11:46:16 +01:00
Milan Zamazal
63a3520e29 hw/virtio: Add a protection against duplicate vu_scmi_stop calls
The QEMU CI fails in virtio-scmi test occasionally.  As reported by
Thomas Huth, this happens most likely when the system is loaded and it
fails with the following error:

  qemu-system-aarch64: ../../devel/qemu/hw/pci/msix.c:659:
  msix_unset_vector_notifiers: Assertion `dev->msix_vector_use_notifier && dev->msix_vector_release_notifier' failed.
  ../../devel/qemu/tests/qtest/libqtest.c:200: kill_qemu() detected QEMU death from signal 6 (Aborted) (core dumped)

As discovered by Fabiano Rosas, the cause is a duplicate invocation of
msix_unset_vector_notifiers via duplicate vu_scmi_stop calls:

  msix_unset_vector_notifiers
  virtio_pci_set_guest_notifiers
  vu_scmi_stop
  vu_scmi_disconnect
  ...
  qemu_chr_write_buffer

  msix_unset_vector_notifiers
  virtio_pci_set_guest_notifiers
  vu_scmi_stop
  vu_scmi_set_status
  ...
  qemu_cleanup

While vu_scmi_stop calls are protected by vhost_dev_is_started()
check, it's apparently not enough.  vhost-user-blk and vhost-user-gpio
use an extra protection, see f5b22d06fb (vhost: recheck dev state in
the vhost_migration_log routine) for the motivation.  Let's use the
same in vhost-user-scmi, which fixes the failure above.

Fixes: a5dab090e1 ("hw/virtio: Add boilerplate for vhost-user-scmi device")
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Message-Id: <20230720101037.2161450-1-mzamazal@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
2023-08-03 16:06:49 -04:00
Milan Zamazal
a5dab090e1 hw/virtio: Add boilerplate for vhost-user-scmi device
This creates the QEMU side of the vhost-user-scmi device which connects to
the remote daemon.  It is based on code of similar vhost-user devices.

Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Message-Id: <20230628100524.342666-2-mzamazal@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-10 16:17:07 -04:00