When loading a segment in real mode, only the base and selector must be modified. The limit needs to be left alone, otherwise big real mode users will hit a #GP due to limit checking (currently this is suppressed because we don't check limits in real mode).
Signed-off-by: Avi Kivity <[email protected]> --- arch/x86/kvm/emulate.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a3b57a2..7281ff8 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1355,19 +1355,15 @@ static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt, bool null_selector = !(selector & ~0x3); /* 0000-0003 are null */ ulong desc_addr; int ret; + u16 dummy; memset(&seg_desc, 0, sizeof seg_desc); if ((seg <= VCPU_SREG_GS && ctxt->mode == X86EMUL_MODE_VM86) || ctxt->mode == X86EMUL_MODE_REAL) { /* set real mode segment descriptor */ + ctxt->ops->get_segment(ctxt, &dummy, &seg_desc, NULL, seg); set_desc_base(&seg_desc, selector << 4); - set_desc_limit(&seg_desc, 0xffff); - seg_desc.type = 3; - seg_desc.p = 1; - seg_desc.s = 1; - if (ctxt->mode == X86EMUL_MODE_VM86) - seg_desc.dpl = 3; goto load; } -- 1.7.11.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
