graphic: 0.953
virtual: 0.931
performance: 0.923
debug: 0.874
semantic: 0.860
device: 0.789
mistranslation: 0.754
architecture: 0.587
peripherals: 0.543
i386: 0.455
user-level: 0.455
permissions: 0.448
boot: 0.413
register: 0.384
risc-v: 0.379
PID: 0.377
vnc: 0.375
socket: 0.370
TCG: 0.368
network: 0.363
ppc: 0.345
VMM: 0.341
arm: 0.219
files: 0.174
hypervisor: 0.170
kernel: 0.162
x86: 0.156
KVM: 0.131
assembly: 0.128

qemu hangs on white windows when connecting to virtual port using -serial option when using Windows OS
Description of problem:
I was trying to connect windbg with a qemu vm. 
First I try using named pipes but all the tutorials I found online result in the qemu windows not even showing. So I give up and trying to use virtual COMs to connect the qemu machine with  windbg over serial port. So I created using professional Virtual come driver a link between COM2 and COM4. Now I run qemu with  -serial COM2 and I do not run windbg than it run correctly and no problem is present. As soon as I run windbg qemu hangs at startup just after the main window is created. The qemu window remains white and windows shows the normal "The application is not responding". It's like the program is in a infinite loop situation. 
Also I noted that If I run qemu and not windbg as soon as the other COM port is connected qemu would stop working and remain frozed. Again showing the "The application is not responding".
If instead of qemu I use other "commercial" software with the same setup (of course there I could use named pipes anyway) I can connect windbg with the machine and do the debug session.