Ein Problem ist später noch aufgetaucht. Wenn der o.g. USB-Stick in den Ruhestand geschickt wurde, war das System nicht mehr benutzbar. Die Log-Ausgabe sah dann wie folgt aus:
Apr 13 20:44:35 media-box kernel: usb 1-2: USB disconnect, device number 3
Apr 13 20:44:35 media-box acpid[889]: input device has been disconnected, fd 8
Apr 13 20:44:35 media-box /usr/lib/gdm3/gdm-x-session[4862]: (II) config/udev: removing device TechnoTrend TVStick CT2-4400
Apr 13 20:44:35 media-box /usr/lib/gdm3/gdm-x-session[4862]: (II) evdev: TechnoTrend TVStick CT2-4400: Close
Apr 13 20:44:35 media-box /usr/lib/gdm3/gdm-x-session[4862]: (II) UnloadModule: "evdev"
Apr 13 20:44:35 media-box kernel: PGD 0
Apr 13 20:44:35 media-box kernel: Oops: 0000 [#1] SMP
Apr 13 20:44:35 media-box kernel: Modules linked in: binfmt_misc rc_tt_1500 si2157 media si2168 dvb_usb_dvbsky dvb_usb_v2 m88ds3103 dvb_core i2c_mux ir_rc6_decoder intel_rapl x86_pkg_temp_thermal intel_poApr 13 20:44:35 media-box kernel: industrialio kvm_intel kvm irqbypass nfsd auth_rpcgss nfs_acl lockd xcbc grace pcbc parport_pc sunrpc ppdev lp parport autofs4 algif_skcipher af_alg dm_crypt hid_genericApr 13 20:44:35 media-box kernel: CPU: 2 PID: 3064 Comm: kdvb-ad-0-fe-0 Not tainted 4.8.0-46-generic #49~16.04.1-Ubuntu
Apr 13 20:44:35 media-box kernel: Hardware name: /NUC5i3RYB, BIOS RYBDWi35.86A.0355.2016.0224.1501 02/24/2016
Apr 13 20:44:35 media-box kernel: task: ffff8de4d8421d80 task.stack: ffff8de4daa08000
Apr 13 20:44:35 media-box kernel: RIP: 0010:[<ffffffffc09f89c6>] [<ffffffffc09f89c6>] si2168_sleep+0x26/0xe0 [si2168]
Apr 13 20:44:35 media-box kernel: RSP: 0018:ffff8de4daa0bdb0 EFLAGS: 00010246
Apr 13 20:44:35 media-box kernel: RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8de4daca91f8 Apr 13 20:44:35 media-box kernel: RDX: 0000000080000000 RSI: 0000000000000282 RDI: ffff8de4df4db830 Apr 13 20:44:35 media-box kernel: RBP: ffff8de4daa0bdf0 R08: 0000000000000000 R09: 0000000000000000
Apr 13 20:44:35 media-box kernel: R10: 00000000000001af R11: ffff8de4d9795900 R12: ffff8de4df4db830
Apr 13 20:44:35 media-box kernel: R13: ffff8de4de978000 R14: ffff8de4de9785f0 R15: 00000000000000d4
Apr 13 20:44:35 media-box kernel: FS: 0000000000000000(0000) GS:ffff8de4e6d00000(0000) knlGS:0000000000000000
Apr 13 20:44:35 media-box kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Apr 13 20:44:35 media-box kernel: CR2: 00000000000000c0 CR3: 000000015d233000 CR4: 00000000003406e0
Apr 13 20:44:35 media-box kernel: Stack:
Apr 13 20:44:35 media-box kernel: dead000000000200 0000000000000000 0000000100096c79 ffffffffb54f3e80
Apr 13 20:44:35 media-box kernel: ffff8de4d8421d80 00000000ddf29cc9 ffff8de4de9784a8 ffff8de4df4db830
Apr 13 20:44:35 media-box kernel: ffff8de4daa0be28 ffffffffc09c4a6b ffff8de4daa0be28 ffff8de4daca9101
Apr 13 20:44:35 media-box kernel: Call Trace:
Apr 13 20:44:35 media-box kernel: [<ffffffffb54f3e80>] ? del_timer_sync+0x50/0x50
Apr 13 20:44:35 media-box kernel: [<ffffffffc09c4a6b>] dvb_usb_fe_sleep+0x6b/0x1b0 [dvb_usb_v2]
Apr 13 20:44:35 media-box kernel: [<ffffffffc09e1831>] dvb_frontend_thread+0x291/0x700 [dvb_core]
Apr 13 20:44:35 media-box kernel: [<ffffffffb54c7470>] ? wake_atomic_t_function+0x60/0x60
Apr 13 20:44:35 media-box kernel: [<ffffffffc09e15a0>] ? dtv_set_frontend+0x410/0x410 [dvb_core]
Apr 13 20:44:35 media-box kernel: [<ffffffffb54a3fa8>] kthread+0xd8/0xf0
Apr 13 20:44:35 media-box kernel: [<ffffffffb5c9aa1f>] ret_from_fork+0x1f/0x40
Apr 13 20:44:35 media-box kernel: [<ffffffffb54a3ed0>] ? kthread_create_on_node+0x1e0/0x1e0
Apr 13 20:44:35 media-box kernel: Code: 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 83 ec 30 48 8b 9f 08 03 00 00 65 48 8b 04 25 28 00 00 00 48 89 45 e8 31 c0 <4c> 8b a3 c0 00 00 00 0f 1f 44 00 Apr 13 20:44:35 media-box kernel: RIP [<ffffffffc09f89c6>] si2168_sleep+0x26/0xe0 [si2168]
Apr 13 20:44:35 media-box kernel: RSP <ffff8de4daa0bdb0>
Apr 13 20:44:35 media-box kernel: CR2: 00000000000000c0
Apr 13 20:44:35 media-box kernel: ---[ end trace bcba26728ff0b040 ]---
Apr 13 20:44:35 media-box kernel: BUG: unable to handle kernel paging request at 00000000ddf29cc9
Apr 13 20:44:35 media-box kernel: IP: [<ffffffffb54c6d7b>] __wake_up_common+0x2b/0x90
Apr 13 20:44:35 media-box kernel: PGD 0 Apr 13 20:44:35 media-box kernel: Oops: 0000 [#2] SMP
Apr 13 20:44:35 media-box kernel: Modules linked in: binfmt_misc rc_tt_1500 si2157 media si2168 dvb_usb_dvbsky dvb_usb_v2 m88ds3103 dvb_core i2c_mux ir_rc6_decoder intel_rapl x86_pkg_temp_thermal intel_poApr 13 20:44:35 media-box kernel: industrialio kvm_intel kvm irqbypass nfsd auth_rpcgss nfs_acl lockd xcbc grace pcbc parport_pc sunrpc ppdev lp parport autofs4 algif_skcipher af_alg dm_crypt hid_genericApr 13 20:44:35 media-box kernel: CPU: 2 PID: 3064 Comm: kdvb-ad-0-fe-0 Tainted: G D 4.8.0-46-generic #49~16.04.1-Ubuntu
Apr 13 20:44:35 media-box kernel: Hardware name: /NUC5i3RYB, BIOS RYBDWi35.86A.0355.2016.0224.1501 02/24/2016
lines 5149-5191
Nach ein bisschen Recherche habe ich eine udev-Regel hinterlegt mit folgendem Inhalt, die den Stromsparzustand verhindern soll,:
ACTION=="add", SUBSYSTEM=="usb", ATTRS{idVendor}=="0b48", ATTR{idProduct}=="3014", ATTR{product}=="TechnoTrend AG TT-TVStick CT2-4400", TEST=="power/control", ATTR{power/control}:="on"
Damit gab es seither keine weiteren Probleme.