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It isn't good to ask users to update >>> CRIU to work on new kernels, but here are reasons and event improvements >>> for CRIU, so I think it's worth it. >> >> I agree, any API to create timers with specified id-s would work for new >> CRIU versions. > > The real question is whether this will cause any upheaval when a new > kernel meets a non-updated CRIU stack. Creation of posix timer would hang forever in this loop https://github.com/checkpoint-restore/criu/blob/33dd66c6fc93c47213aaa0447a94d97ba1fa56ba/criu/pie/restorer.c#L1185 if old criu is run on new kernel (without consecutive id allocation) AFAICS. > You know the UABI regression rules of the kernel... > > Thanks, > > tglx > -- Best regards, Tikhomirov Pavel Senior Software Developer, Virtuozzo.