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QEMU with KQemu accelerator module

I've been playing around with qemu lately and there is a little tip I ran into that helps in getting the kqemu module running if you have Win4lin installed. This is from the Win4Lin support because T…

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Avery J. Parker

IT veteran, maker educator, and author of Network Ninja, 3D Printing Mastery, and AI Workflow Mastery. Business IT: Diversified Tech Solutions.

I've been playing around with qemu lately and there is a little tip I ran into that helps in getting the kqemu module running if you have Win4lin installed.


This is from the Win4Lin support because THEIR module could conflict with it. They suggest the following.

mknod -m 0666 /dev/kqemu c 239 0
insmod /lib/modules/2.6.8.1-12mdk/kernel/3rdparty/kqemu/kqemu.ko major=239

(The insmod directory should be the place the kqemu.ko module exists. major=239 tells it to use the major character defined in the mknod device.) The default is 250, that apparently conflicts with the Win4lin kernel module. Weird stuff, but the acceleration is worth the time spent to load the module. Another note if you have a peculiar setup like mine and qemu was not compiled for kqemu and you don't want to recompile after getting kqemu set... you'll likely be seeing this error at boot.
Could not open '/dev/qvm86' - QEMU acceleration layer not activated

The fix, (if you have kqemu set) is to ...

ln -s /dev/kqemu /dev/qvm86