On 11/21/2016 08:53 AM, Andrew Cooper wrote: > On 21/11/16 13:38, Boris Ostrovsky wrote: >> On 11/21/2016 05:40 AM, Andrew Cooper wrote: >>> On 16/11/16 10:51, Andrew Cooper wrote: >>>> vmcb->nextrip can legitimately be less than vmcb->rip when execution wraps >>>> back around to 0. Instead, complain if the reported length is greater >>>> than 15 >>>> and use x86_decode_insn() as a fallback. >> Why do we need to complain? In the case that you are addressing by this >> patch wouldn't that be the expected result (length>15)? > No. An instruction crossing the boundary looks like: > > e.g. nextrip = 0x3, rip = 0xfffffffffffffffe > > As this is all evaluated in unsigned long arithmetic, nextrip - rip > evaluates to 5, which is correct.
Oh, right. Reviewed-by: Boris Ostrovsky <boris.ostrov...@oracle.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
