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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: IVJKwOzaynGFP3nDcA9xpKN4QhCA0eG3BvR8TEIhViRwzNaXLGA2m/2CwsObsZnKY4KpcXUi8kyWRy9Yxz9DETHvFb/C54yRWQLlfoECSdEQR9Jv9UcCuXKz0iUjuTesxal9bgpcpO7s8Fj8pWh4JcEjXxtt+OmMIFEUS+YYyRJgiVIucKMKCibYP1qQZJWzd+EzoFJNSt0q2062fzoq/PnNL45bXYEQA0PiVjva+1yKFMZ6JIx/n8ZEXCujmA7M52p3GeJWpMaY0oaKC52zNcdGYf4fGbQC/g+Mfr35gp1C1I+rHeczs+nFRveoNV+wUc+aVzblfw8Q/0TPtmxKWvehCzDmAoJp+NPsim13Ff3Y75DoaAklV8VSntufeCWZJ5qcSh6K+EqRdMCI8YEQ3Ie7kR4eFt0D14fRLXpOyPPOvoe8bc0XiXdd4aW0UDjF X-ExternalRecipientOutboundConnectors: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-Auto-Response-Suppress: DR, OOF, AutoReply X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Oct 2026 15:53:25.3536 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: ed954874-ac86-4ce3-c1fc-08df29421dc8 X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-AuthSource: AM7PEPF00000056.EURPRD83.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: Internet X-MS-Exchange-Transport-CrossTenantHeadersStamped: AMDPR08MB999867 > 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/20261013-vfio= _v1-v2-0-433455c0a294@virtuozzo.com?part=3D20