[28406.185438] usb 4-1.1: new full-speed USB device number 8 using ehci-pci
[28406.273043] cdc_acm 4-1.1:1.0: ttyACM0: USB ACM device
[28425.108614] traps: avrdude[10140] trap divide error ip:442b32 sp:7ffd7de30cb0 error:0 in avrdude[400000+6a000]
[28476.249604] traps: avrdude[10480] trap divide error ip:442b32 sp:7ffdd8fc46a0 error:0 in avrdude[400000+6a000]
[28711.966680] traps: avrdude[11349] trap divide error ip:442b32 sp:7ffe1add72b0 error:0 in avrdude[400000+6a000]
[28773.009144] traps: avrdude[11723] trap divide error ip:442b32 sp:7ffcb8f4f680 error:0 in avrdude[400000+6a000]
[28822.528757] traps: avrdude[12146] trap divide error ip:442b32 sp:7ffd7e4a9e50 error:0 in avrdude[400000+6a000]
[28858.676939] usb 4-1.1: USB disconnect, device number 8
[28862.441145] usb 4-1.1: new full-speed USB device number 9 using ehci-pci
[28862.528959] cdc_acm 4-1.1:1.0: ttyACM0: USB ACM device
[28880.203999] traps: avrdude[12441] trap divide error ip:442b32 sp:7ffdcb03cb10 error:0 in avrdude[400000+6a000]
[29056.805930] traps: avrdude[13030] trap divide error ip:442b32 sp:7ffd44f17870 error:0 in avrdude[400000+6a000]
[29106.242926] usb 4-1.1: USB disconnect, device number 9
[29110.774175] usb 4-1.1: new full-speed USB device number 10 using ehci-pci
[29110.861668] cdc_acm 4-1.1:1.0: ttyACM0: USB ACM device
[29125.523987] traps: avrdude[13456] trap divide error ip:442b32 sp:7ffcfcb43170 error:0 in avrdude[400000+6a000]
[29194.476713] usb 4-1.1: USB disconnect, device number 10
[29204.125889] usb 4-1.7: new full-speed USB device number 11 using ehci-pci
[29204.213806] cdc_acm 4-1.7:1.0: ttyACM0: USB ACM device
[29233.850653] traps: avrdude[13881] trap divide error ip:442b32 sp:7ffd50874520 error:0 in avrdude[400000+6a000]
[29270.434462] usb 4-1.7: USB disconnect, device number 11
[29278.802640] usb 4-1.7: new full-speed USB device number 12 using ehci-pci
[29278.890312] cdc_acm 4-1.7:1.0: ttyACM0: USB ACM device
[29473.140399] traps: avrdude[14905] trap divide error ip:442b32 sp:7fff3d028f40 error:0 in avrdude[400000+6a000]
[29620.942802] traps: avrdude[16539] trap divide error ip:442b32 sp:7ffd94044d70 error:0 in avrdude[400000+6a000]