device: 0.924
socket: 0.922
virtual: 0.847
network: 0.813
architecture: 0.804
vnc: 0.798
performance: 0.779
graphic: 0.761
hypervisor: 0.758
semantic: 0.725
peripherals: 0.712
mistranslation: 0.669
PID: 0.655
VMM: 0.655
register: 0.646
kernel: 0.615
risc-v: 0.613
permissions: 0.602
debug: 0.595
boot: 0.557
assembly: 0.530
arm: 0.476
TCG: 0.474
user-level: 0.470
KVM: 0.452
ppc: 0.443
files: 0.442
i386: 0.439
x86: 0.382

qemu will detach usbredir if backend chardev socket disconnect
Description of problem:
When using the usbredir device in the VM, initiate a hot migration to the VM.  
After the migration is completed, the drive letter of the usb in the VM has changed.  
Actually the device has been unplugged and re-plugged in the VM.  
I think we should keep the plugged state of the device after the migration?
Steps to reproduce:
1. Start a usbredirserver `usbredirserver -p 7000 -v 4 5-2`;
2. Start a VM with a usbredir device attached to it;
3. Mount the usb device in the VM;
4. Migrate the VM, after the migration done, wait a minute，the drive letter of the usb in the VM has changed.
Additional information:
I've found this bug https://bugzilla.redhat.com/show_bug.cgi?id=1254971, this is just to allow the chardev to be reconnected in time when it is disconnected.   
Can we make chardev reconnect without unpluging the usbredir device?