Maciej W. Rozycki wrote: > I can't see a reason why to handle this option in > system-specific code. > How about "there will be likely no such CPUs/systems in the future"? Your patch will force every new CPU to add FPUEX option to the cpu_option, where apparently no place really need to use it. Leaving FPU exception enabled for a CPU that does not generate FPU exception is acceptable. (because it does *not* generate FPU exceptions). And hooking up/dispatching the FPU exception interrupt is system-specific already anyway. It, however, makes sense to provide a common wrapper code for fpu interrupt to jump to fpu exception handling code. Over-abstraction can make the picture cloudy rather than clear. My 2 cents. Jun
