At least on Westmere+ CPUs (first gen Core i3/i5/i7) KVM can run "unrestricted guest" mode which behaves like real mode and seems just as fast as vm86() but it traps less than vm86 so some things that dosemu depends upon (e.g. that INTs are trapped) do not work. That can be worked around though with some more coding.
In our case the ability to get hardware interrupts routed through to the DOS emulator's code in a prompt manner is VERY important. In fact that is one major reason we have generally not played with the 64-bit version very much in the past.
By "prompt" I mean less than 10us or so which was no trouble in the native 286/DOS era, and today should not be a problem given a typical CPU can execute some 30k instructions in that time, but we know that is not how software bloat and indirection go :(
Regards, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html