Il 17/08/2014 23:09, Paolo Bonzini ha scritto: > Il 17/08/2014 21:32, Nadav Amit ha scritto: >> This reverts commit 5045b468037dfe1c848827ce10e99d87f5669160. Although the >> cs.dpl=cs.rpl check is mentioned in table 7-1 of the SDM as causing a #TSS >> exception, it is not mentioned in table 6-6 that lists "invalid TSS >> conditions" >> which cause #TSS exceptions. As it causes some tests, which pass on >> bare-metal, >> to fail - it should be reverted. > > Right. However, I think reverting the patch is too big a hammer. We > still need in_task_switch to raise TS_VECTOR instead of GP_VECTOR, so I > propose instead something like: > > diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > index 56657b0bb3bb..cd230b035514 100644 > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -1468,7 +1468,7 @@ static int __load_segment_descriptor(struct > x86_emulate_ctxt *ctxt, > return ret; > > err_code = selector & 0xfffc; > - err_vec = GP_VECTOR; > + err_vec = in_task_switch ? TS_VECTOR : GP_VECTOR; > > /* can't load system descriptor into segment selector */ > if (seg <= VCPU_SREG_GS && !seg_desc.s) > @@ -1491,9 +1491,6 @@ static int __load_segment_descriptor(struct > x86_emulate_ctxt *ctxt, > goto exception; > break; > case VCPU_SREG_CS: > - if (in_task_switch && rpl != dpl) > - goto exception; > - > if (!(seg_desc.type & 8)) > goto exception; >
Also, what about the rpl > cpl test below, for non-conforming code segments? It is not mentioned in table 6-6 either. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
