Initialize the cpu topology and therefore also the cpu to node mapping much earlier. Fixes this warning and subsequent crashes when using the fake numa emulation mode on s390: WARNING: CPU: 0 PID: 1 at include/linux/cpumask.h:121 select_task_rq+0xe6/0x1a8 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0-rc6-00001-ge9d867a67fd0-dirty #28 task: 00000001dd270008 ti: 00000001eccb4000 task.ti: 00000001eccb4000 Krnl PSW : 0404c00180000000 0000000000176c56 (select_task_rq+0xe6/0x1a8) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 Call Trace: ([<0000000000176c30>] select_task_rq+0xc0/0x1a8) ([<0000000000177d64>] try_to_wake_up+0x2e4/0x478) ([<000000000015d46c>] create_worker+0x174/0x1c0) ([<0000000000161a98>] alloc_unbound_pwq+0x360/0x438) ([<0000000000162550>] apply_wqattrs_prepare+0x200/0x2a0) ([<000000000016266a>] apply_workqueue_attrs_locked+0x7a/0xb0) ([<0000000000162af0>] apply_workqueue_attrs+0x50/0x78) ([<000000000016441c>] __alloc_workqueue_key+0x304/0x520) ([<0000000000ee3706>] default_bdi_init+0x3e/0x70) ([<0000000000100270>] do_one_initcall+0x140/0x1d8) ([<0000000000ec9da8>] kernel_init_freeable+0x220/0x2d8) ([<0000000000984a7a>] kernel_init+0x2a/0x150) ([<00000000009913fa>] kernel_thread_starter+0x6/0xc) ([<00000000009913f4>] kernel_thread_starter+0x0/0xc) Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>