| Message ID | 20230818095041.1973309-16-xiaoyao.li@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | TDX QEMU support | expand |
On Fri, Aug 18, 2023 at 05:49:58AM -0400, Xiaoyao Li wrote: > Bit 28 of TD attribute, named SEPT_VE_DISABLE. When set to 1, it disables > EPT violation conversion to #VE on guest TD access of PENDING pages. > > Some guest OS (e.g., Linux TD guest) may require this bit as 1. > Otherwise refuse to boot. > > Add sept-ve-disable property for tdx-guest object, for user to configure > this bit. > > Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> > Acked-by: Gerd Hoffmann <kraxel@redhat.com> > --- > qapi/qom.json | 4 +++- > target/i386/kvm/tdx.c | 24 ++++++++++++++++++++++++ > 2 files changed, 27 insertions(+), 1 deletion(-) > > diff --git a/qapi/qom.json b/qapi/qom.json > index 2ca7ce7c0da5..cc08b9a98df9 100644 > --- a/qapi/qom.json > +++ b/qapi/qom.json > @@ -871,10 +871,12 @@ > # > # Properties for tdx-guest objects. > # > +# @sept-ve-disable: bit 28 of TD attributes (default: 0) This description isn't very useful as it forces the user to go off and read the TDX specification to find out what bit 28 means. You've got a more useful description in the commit message, so please use that in the docs too. eg something like this @sept-ve-disable: toggle bit 28 of TD attributes to control disabling of EPT violation conversion to #VE on guest TD access of PENDING pages. Some guest OS (e.g. Linux TD guest) may require this set, otherwise they refuse to boot. > +# > # Since: 8.2 > ## > { 'struct': 'TdxGuestProperties', > - 'data': { }} > + 'data': { '*sept-ve-disable': 'bool' } } > > ## > # @ThreadContextProperties: > diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c > index 3d313ed46bd1..22130382c0c5 100644 > --- a/target/i386/kvm/tdx.c > +++ b/target/i386/kvm/tdx.c > @@ -32,6 +32,8 @@ > (1U << KVM_FEATURE_PV_SCHED_YIELD) | \ > (1U << KVM_FEATURE_MSI_EXT_DEST_ID)) > > +#define TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE BIT_ULL(28) > + > #define TDX_ATTRIBUTES_MAX_BITS 64 > > static FeatureMask tdx_attrs_ctrl_fields[TDX_ATTRIBUTES_MAX_BITS] = { > @@ -501,6 +503,24 @@ out: > return r; > } > > +static bool tdx_guest_get_sept_ve_disable(Object *obj, Error **errp) > +{ > + TdxGuest *tdx = TDX_GUEST(obj); > + > + return !!(tdx->attributes & TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE); > +} > + > +static void tdx_guest_set_sept_ve_disable(Object *obj, bool value, Error **errp) > +{ > + TdxGuest *tdx = TDX_GUEST(obj); > + > + if (value) { > + tdx->attributes |= TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE; > + } else { > + tdx->attributes &= ~TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE; > + } > +} > + > /* tdx guest */ > OBJECT_DEFINE_TYPE_WITH_INTERFACES(TdxGuest, > tdx_guest, > @@ -516,6 +536,10 @@ static void tdx_guest_init(Object *obj) > qemu_mutex_init(&tdx->lock); > > tdx->attributes = 0; > + > + object_property_add_bool(obj, "sept-ve-disable", > + tdx_guest_get_sept_ve_disable, > + tdx_guest_set_sept_ve_disable); > } > > static void tdx_guest_finalize(Object *obj) > -- > 2.34.1 > With regards, Daniel
On 8/22/2023 2:27 PM, Markus Armbruster wrote: > Daniel P. Berrangé <berrange@redhat.com> writes: > >> On Fri, Aug 18, 2023 at 05:49:58AM -0400, Xiaoyao Li wrote: >>> Bit 28 of TD attribute, named SEPT_VE_DISABLE. When set to 1, it disables >>> EPT violation conversion to #VE on guest TD access of PENDING pages. >>> >>> Some guest OS (e.g., Linux TD guest) may require this bit as 1. >>> Otherwise refuse to boot. >>> >>> Add sept-ve-disable property for tdx-guest object, for user to configure >>> this bit. >>> >>> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> >>> Acked-by: Gerd Hoffmann <kraxel@redhat.com> >>> --- >>> qapi/qom.json | 4 +++- >>> target/i386/kvm/tdx.c | 24 ++++++++++++++++++++++++ >>> 2 files changed, 27 insertions(+), 1 deletion(-) >>> >>> diff --git a/qapi/qom.json b/qapi/qom.json >>> index 2ca7ce7c0da5..cc08b9a98df9 100644 >>> --- a/qapi/qom.json >>> +++ b/qapi/qom.json >>> @@ -871,10 +871,12 @@ >>> # >>> # Properties for tdx-guest objects. >>> # >>> +# @sept-ve-disable: bit 28 of TD attributes (default: 0) >> >> This description isn't very useful as it forces the user to go off and >> read the TDX specification to find out what bit 28 means. You've got a > > Seconded. > >> more useful description in the commit message, so please use that >> in the docs too. eg something like this >> >> @sept-ve-disable: toggle bit 28 of TD attributes to control disabling >> of EPT violation conversion to #VE on guest >> TD access of PENDING pages. Some guest OS (e.g. >> Linux TD guest) may require this set, otherwise >> they refuse to boot. > > But please format like > > # @sept-ve-disable: toggle bit 28 of TD attributes to control disabling > # of EPT violation conversion to #VE on guest TD access of PENDING > # pages. Some guest OS (e.g. Linux TD guest) may require this to > # be set, otherwise they refuse to boot. > Thank you, Daniel and Markus. Will use above in the next version. > to blend in with recent commit a937b6aa739 (qapi: Reformat doc comments > to conform to current conventions). > >>> +# >>> # Since: 8.2 >>> ## >>> { 'struct': 'TdxGuestProperties', >>> - 'data': { }} >>> + 'data': { '*sept-ve-disable': 'bool' } } >>> >>> ## >>> # @ThreadContextProperties: > > [...] >
diff --git a/qapi/qom.json b/qapi/qom.json index 2ca7ce7c0da5..cc08b9a98df9 100644 --- a/qapi/qom.json +++ b/qapi/qom.json @@ -871,10 +871,12 @@ # # Properties for tdx-guest objects. # +# @sept-ve-disable: bit 28 of TD attributes (default: 0) +# # Since: 8.2 ## { 'struct': 'TdxGuestProperties', - 'data': { }} + 'data': { '*sept-ve-disable': 'bool' } } ## # @ThreadContextProperties: diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c index 3d313ed46bd1..22130382c0c5 100644 --- a/target/i386/kvm/tdx.c +++ b/target/i386/kvm/tdx.c @@ -32,6 +32,8 @@ (1U << KVM_FEATURE_PV_SCHED_YIELD) | \ (1U << KVM_FEATURE_MSI_EXT_DEST_ID)) +#define TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE BIT_ULL(28) + #define TDX_ATTRIBUTES_MAX_BITS 64 static FeatureMask tdx_attrs_ctrl_fields[TDX_ATTRIBUTES_MAX_BITS] = { @@ -501,6 +503,24 @@ out: return r; } +static bool tdx_guest_get_sept_ve_disable(Object *obj, Error **errp) +{ + TdxGuest *tdx = TDX_GUEST(obj); + + return !!(tdx->attributes & TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE); +} + +static void tdx_guest_set_sept_ve_disable(Object *obj, bool value, Error **errp) +{ + TdxGuest *tdx = TDX_GUEST(obj); + + if (value) { + tdx->attributes |= TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE; + } else { + tdx->attributes &= ~TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE; + } +} + /* tdx guest */ OBJECT_DEFINE_TYPE_WITH_INTERFACES(TdxGuest, tdx_guest, @@ -516,6 +536,10 @@ static void tdx_guest_init(Object *obj) qemu_mutex_init(&tdx->lock); tdx->attributes = 0; + + object_property_add_bool(obj, "sept-ve-disable", + tdx_guest_get_sept_ve_disable, + tdx_guest_set_sept_ve_disable); } static void tdx_guest_finalize(Object *obj)