On Wed, Jul 7, 2010 at 10:23 PM, Mohammed Gamal <m.gamal005@xxxxxxxxx> wrote: > After some conversation with Avi concerning why unreal mode has been seen to work > with KVM on Intel. It clears out the scenario is caused as follows: > > - guest enters big real mode > - kvm squashes limit to 64k-1 > - guest executes instructions with offset > 64k > - cpu issues #GP due to limit violation > - kvm handle_rmode_exception() -> emulator > - emulator ignores limit, emulates instruction > > With these applied I am getting vmentry failures with SeaBIOS and > gPXE. So it's needless to say that these patches are not meant for merging! Thanks for testing with gPXE and please don't hesitate to discuss issues you hit with gPXE on gpxe-devel@xxxxxxxxxxxxxx I look forward to your big real mode work :). > Mohammed Gamal (3): > Add helper methods to get segment limits > x86 emulator: Add cs_base() helper > x86 emulator: Add segment limit checks and helper functions > > arch/x86/include/asm/kvm_emulate.h | 1 + > arch/x86/include/asm/kvm_host.h | 1 + > arch/x86/kvm/emulate.c | 123 +++++++++++++++++++++++++++++------- > arch/x86/kvm/svm.c | 8 +++ > arch/x86/kvm/vmx.c | 8 +++ > arch/x86/kvm/x86.c | 12 ++++ > 6 files changed, 130 insertions(+), 23 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 > Stefan -- 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
