On 22/03/2018 09:34, Wanpeng Li wrote: > From: Wanpeng Li <[email protected]> > > Explicit segment overides other than %fs and %gs are documented as ignored by > both Intel and AMD. > > In practice, this means that: > > * Explicit uses of %ss don't actually yield #SS[0] for non-canonical > memory references. > * Explicit uses of %{e,c,d}s don't override %rbp/%rsp-based memory references > to yield #GP[0] for non-canonical memory references. > > Cc: Paolo Bonzini <[email protected]> > Cc: Radim Krčmář <[email protected]> > Signed-off-by: Wanpeng Li <[email protected]> > --- > arch/x86/kvm/emulate.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > index dd88158..5091255 100644 > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -5148,8 +5148,10 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, > void *insn, int insn_len) > case 0x2e: /* CS override */ > case 0x36: /* SS override */ > case 0x3e: /* DS override */ > - has_seg_override = true; > - ctxt->seg_override = (ctxt->b >> 3) & 3; > + if (mode != X86EMUL_MODE_PROT64) { > + has_seg_override = true; > + ctxt->seg_override = (ctxt->b >> 3) & 3; > + } > break; > case 0x64: /* FS override */ > case 0x65: /* GS override */ >
Testcase, please... Paolo
