On Thu, May 11, 2017 at 10:56:42AM +0800, Jason Wang wrote: > > > On 2017年05月10日 16:01, Peter Xu wrote: > >When device-iotlb is not specified, we should fail this check. > > > >Signed-off-by: Peter Xu <pet...@redhat.com> > >--- > > hw/i386/intel_iommu.c | 13 ++++++++++++- > > 1 file changed, 12 insertions(+), 1 deletion(-) > > > >diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c > >index 05ae631..1a7eba2 100644 > >--- a/hw/i386/intel_iommu.c > >+++ b/hw/i386/intel_iommu.c > >@@ -836,6 +836,8 @@ static int vtd_dev_to_context_entry(IntelIOMMUState *s, > >uint8_t bus_num, > > { > > VTDRootEntry re; > > int ret_fr; > >+ bool type_fail = false; > >+ X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s); > > ret_fr = vtd_get_root_entry(s, bus_num, &re); > > if (ret_fr) { > >@@ -872,10 +874,19 @@ static int vtd_dev_to_context_entry(IntelIOMMUState > >*s, uint8_t bus_num, > > } else { > > switch (vtd_ce_get_type(ce)) { > > case VTD_CONTEXT_TT_MULTI_LEVEL: > >- /* fall through */ > >+ /* Always supported */ > >+ break; > > case VTD_CONTEXT_TT_DEV_IOTLB: > >+ if (!x86_iommu->dt_supported) { > >+ type_fail = true; > >+ } > > break; > > default: > >+ /* Unknwon type */ > >+ type_fail = true; > >+ break; > >+ } > >+ if (type_fail) { > > trace_vtd_ce_invalid(ce->hi, ce->lo); > > return -VTD_FR_CONTEXT_ENTRY_INV; > > } > > How about e.g exclude the type if not supported in vtd_ce_get_type()? This > looks better than using something like type_fail.
(after a quick discussion with Jason offlist) I'll keep current vtd_ce_get_type() since there are other places that used it, and introduce another vtd_ce_type_check() to make codes more elegant (and get rid of type_fail variable). Thanks. -- Peter Xu