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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: tnO9iVbB5YvVYB0rCMabE50u/r45cjyjJpBeSPGg+cZfy8IICb+9xdi3XycqOwxOkxz+s6dD8gkNK0su5unLFUGeUQVI0BOAiFa+p+BSK95MWE/mzOYhggtx4MyIAYyyMZoG52ddkQw0gtUxZYG9hTu0RRGmSi0pSEsDFMJyek8RaOgWWW/D0RhYtpgIAIVGoYboKOPKnvvZDsCuuADZwrawVQ5CusW4NeKEHUtXxcPzEtK5CXx8zaaGFlx7WsZStnjZrvfCIae2YcmCRQeFsSZaNDHrhNSoxCknOj7hpWgzjUI1cbPF8i+FMsQPtp3/IxE/ojuFsYQhHiGpL+slZkZby3qqoAMoln8uA81NiBywK29a0S3xHI8kYqlm6D6iBcGbW7WzsFTZCfxpnf9qB9Rj5l6mN/wLmn4Fw7WuCRVzW26Nw8Ue9eg8rmTYqiFZ X-ExternalRecipientOutboundConnectors: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Nov 2026 14:29:09.2986 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 340e5670-7fa7-4f98-5818-08df39b6d2d2 X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-AuthSource: AMS0EPF0000056A.eurprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: Internet X-MS-Exchange-Transport-CrossTenantHeadersStamped: MMZPR08MB669593 > 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/20261103-vfio= _v1-v7-0-4467fdccbbe6@virtuozzo.com?part=3D29