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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: dbfR8oGvdqbHkt8gU+eykJupj0N/sgmeYokXUbpqNk7yERmebH/SvfvzBeF3R7WzGR2Z26vZ7yvUMbWWH/pjj69M1xNbx7Nyv8z+lGnfwsoglwIT5vRBwslPfH9iPFOArLIHNUZnKqQ3Skc2bZZqyMLecijXDcHqzg+/eSEjo+WWgF0wuDjWzDgqAfQEhYV6aKhRq1WkvFBHOE5+2iQcjJQq17vwLG0zXXJCkD1uBRn9WAKz6vNgS1SIy18mLbMHqcDf6Alz1VZZb38gB0/M8f345M+lTbteUIEr2cLP4luGv7IvZc8TScgqmuIil2pdce5fC6yhQXEA8foou1bnq5zuFlG6wmOeJGQAfoCBXkhEO3as++A4X6VSaLMhbhgnq0yDOMh42g5iIJFKjC4eIrDsCLNRN1pjTHzqXIH7tw/NfdLWeQIZsQ//dGFq/2KQ X-ExternalRecipientOutboundConnectors: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Oct 2026 17:01:20.2361 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 890c1c42-b126-4ee8-0457-08df2ecbc382 X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-AuthSource: DU2PEPF00028CFC.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: Internet X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV1PR08MB7362 > With VFIO devices, KVM is closed on the source when the migration > completes, so that the new QEMU can create its own KVM VM with the same > devices. That is done from a migration notifier, which for cpr-exec > runs before cpr_exec_cb(). But cpr_exec_cb() may still give up, when > the memory can't be preserved or execve() fails, and resume the VM in > the old QEMU. A VM without KVM can't resume: kvm_close() removes the > vCPU threads, and the first KVM ioctl of vm_start() aborts QEMU > (KVM_SET_CLOCK in kvmclock_vm_state_change()). >=20 > cpr-exec doesn't need it anyway: the KVM fds are close-on-exec, so the > kernel closes them during execve(), before the new QEMU runs, and > kvm_vm_release() tears down the irqfds then. Keep the notifier for > cpr-transfer only, where the source process lives on. >=20 > Tested on the vfio-net rig: cpr-exec 5/5; a cpr-exec aborted in > preserve_ram() and one with a bogus cpr-exec-command both left the VM > running with no lost pings, and a later cpr-exec completed. >=20 > Signed-off-by: Andrey Drobyshev Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.vzint.dev/#/patchset/20261020-vfio= _v1-v4-0-83a5668230e5@virtuozzo.com?part=3D25