At 03/22/2012 03:12 AM, Anthony Liguori Wrote: > On 03/15/2012 06:46 AM, Avi Kivity wrote: >> On 03/15/2012 01:25 PM, Jan Kiszka wrote: >>>>> >>>> There was such vm exit (KVM_EXIT_HYPERCALL), but it was deemed to be a >>>> bad idea. >>> >>> BTW, this would help a lot in emulating hypercalls of other hypervisors >>> (or of KVM's VAPIC in the absence of in-kernel irqchip - I had to jump >>> through hoops therefore) in user space. Not all those hypercall handlers >>> actually have to reside in the KVM module. >>> >> >> That is true. On the other hand the hypercall ABI might go to pieces if >> there was no central implementation. > > Just declare that outl 0x505 is a megaultracall and s/vmcall/outb/g and > call it a day. Why use 0x505? Is it a reserved port, and it will not be used by any device? How can I get all reserved port? Thanks Wen Congyang > > The performance difference between vmcall and outl is so tiny compared > to the cost of dropping to userspace that it really doesn't matter which > instruction is used. > > Regards, > > Anthony Liguori > >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
