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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: ApidMv9ZY7uHOqalOQzdYOYAls4izPN52PFV4qnitPddqKMHNPS0g7dfKagxaQUkZg/TRG4jI0Y/CXfDoaSlnLkJjQxIaMvRTbsQ9nSM1usYy+hDs47Hp5sOGz0E7KYEdp9UqRFPaW/5sv0LoOC5HH2InvWXvOYNeUlgYnZsUOYBXL8HReow844v6Yjc6mQL4G4NIDulPe3O+oPnIPr8alBC+RjoKM4NGU0TE+t45uwrp05MZOMtESq74cTwFfGG+vJB3rv4SmPg4tG0eQOjQBI587Pe3WpQEFDaENrUS5OqBrqCbmWLb2YwxdSAyeZ5q4szBD9MyhJQTZQN1bulVW1hAvEm+NL3Ri2Kl3yWJNXcaFNFZu9bV6w46GG/1qkRXOST/y6U6n5AHYksINoCaRtAbHXJyJEA5diiw+DzpfKEdiV1jo7Rh/0UWGeq4U1E X-ExternalRecipientOutboundConnectors: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Oct 2026 15:52:59.4462 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 347019b8-a7db-4dc4-3cae-08df2b9d8d94 X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-AuthSource: ZR1PEPF0000E6B5.eurprd07.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: Internet X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM8PR08MB5794 > 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/20261016-vfio= _v1-v3-0-47487cb5a8e5@virtuozzo.com?part=3D23