qemu/include
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
..
accel accel/tcg: Move TARGET_TAGGED_ADDRESSES to TCGCPUOps.untagged_addr 2025-05-05 09:24:10 -07:00
authz Prefer 'on' | 'off' over 'yes' | 'no' for bool options 2021-01-29 17:07:53 +00:00
block block: Remove unused callback function *bdrv_aio_pdiscard 2025-04-25 17:06:50 +02:00
chardev chardev/char-hub: implement backend chardev aggregator 2025-02-03 13:57:08 +04:00
crypto crypto: Remove qcrypto_tls_session_get_handshake_status 2025-02-14 15:19:03 -03:00
disas disas: Fix build against Capstone v6 (again) 2024-11-05 10:09:59 +00:00
exec include: Remove 'exec/exec-all.h' 2025-04-30 12:45:05 -07:00
fpu fpu: Move m68k_denormal fmt flag into floatx80_behaviour 2025-02-25 15:32:57 +00:00
gdbstub gdbstub/helpers: Introduce ldtul_$endian_p() helpers 2024-10-15 11:55:09 -03:00
hw vhost-user: return failure if backend crash when live migration 2025-05-14 05:39:15 -04:00
io io: Add a read flag for relaxed EOF 2025-02-14 15:19:04 -03:00
libdecnumber Replace config-time define HOST_WORDS_BIGENDIAN 2022-04-06 10:50:37 +02:00
migration migration: Add save_postcopy_prepare() savevm handler 2025-05-02 11:09:36 -04:00
monitor monitor: Remove obsolete stubs 2024-06-30 19:51:44 +03:00
net net: checksum: Convert data to void * 2024-11-25 13:59:50 +08:00
qapi error: define g_autoptr() cleanup function for the Error type 2025-03-06 06:47:33 +01:00
qemu Pull request 2025-05-09 12:04:19 -04:00
qobject qapi: Move include/qapi/qmp/ to include/qobject/ 2025-02-10 15:33:16 +01:00
qom qom: Make InterfaceInfo[] uses const 2025-04-25 17:00:41 +02:00
scsi hw/ufs: Support for UFS logical unit 2023-09-07 14:01:29 -04:00
semihosting semihosting: Move user-only implementation out-of-line 2025-04-23 14:08:32 -07:00
standard-headers linux-headers: Update to Linux v6.15-rc3 2025-05-09 12:42:28 +02:00
system vhost-user: return failure if backend crash when live migration 2025-05-14 05:39:15 -04:00
tcg tcg: Define INSN_START_WORDS as constant 3 2025-05-01 07:37:13 -07:00
ui ui/egl: support multi-plane dmabuf when egl export/import 2025-05-06 13:39:42 +04:00
user accel/tcg: Remove TARGET_PAGE_DATA_SIZE 2025-05-05 09:24:10 -07:00
elf.h util: spelling fixes 2023-08-31 19:47:43 +02:00
glib-compat.h include/glib-compat.h: Poison g_list_sort and g_slist_sort 2025-05-06 16:02:04 +02:00
qemu-io.h Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
qemu-main.h ui & main loop: Redesign of system-specific main thread event handling 2024-12-31 21:21:34 +01:00