On 30/10/2014 15:06, Radim Krčmář wrote: > APICv traps register writes, so we can't retrieve previous value, but > our code depends on detecting changes. Applied, thanks. Paolo > Apart from disabling APIC register virtualization, we can detect the > change by using extra memory. One value history is enough, but we still > don't want to keep it for every APIC register, for performance reasons. > This leaves us with either a new framework, or exceptions ... > The latter options fits KVM's path better [1,2]. > > And when we already mirror a part of registers, optimizing access is > acceptable [3]. (Squashed to keep bisecters happy.) > > --- > Radim Krčmář (3): > KVM: x86: detect SPIV changes under APICv > KVM: x86: detect LVTT changes under APICv > KVM: x86: optimize some accesses to LVTT and SPIV > > arch/x86/kvm/lapic.c | 32 +++++++++++++++++--------------- > arch/x86/kvm/lapic.h | 8 +++++--- > 2 files changed, 22 insertions(+), 18 deletions(-) > -- 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