From 6016e2972d94c90307b6caf55a8e3aee5424c09b Mon Sep 17 00:00:00 2001 From: Xiaoyao Li Date: Thu, 8 May 2025 10:59:15 -0400 Subject: [PATCH] i386/tdx: Add property sept-ve-disable for tdx-guest object MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Acked-by: Gerd Hoffmann Acked-by: Markus Armbruster Reviewed-by: Daniel P. Berrangé Reviewed-by: Zhao Liu Link: https://lore.kernel.org/r/20250508150002.689633-10-xiaoyao.li@intel.com Signed-off-by: Paolo Bonzini --- qapi/qom.json | 8 +++++++- target/i386/kvm/tdx.c | 23 +++++++++++++++++++++++ 2 files changed, 30 insertions(+), 1 deletion(-) diff --git a/qapi/qom.json b/qapi/qom.json index 3d7e11efc3..5a88d36423 100644 --- a/qapi/qom.json +++ b/qapi/qom.json @@ -1055,10 +1055,16 @@ # @attributes: The 'attributes' of a TD guest that is passed to # KVM_TDX_INIT_VM # +# @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. +# # Since: 10.1 ## { 'struct': 'TdxGuestProperties', - 'data': { '*attributes': 'uint64' } } + 'data': { '*attributes': 'uint64', + '*sept-ve-disable': 'bool' } } ## # @ThreadContextProperties: diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c index 2d2d48c083..32ba3982ff 100644 --- a/target/i386/kvm/tdx.c +++ b/target/i386/kvm/tdx.c @@ -18,6 +18,8 @@ #include "kvm_i386.h" #include "tdx.h" +#define TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE BIT_ULL(28) + static TdxGuest *tdx_guest; static struct kvm_tdx_capabilities *tdx_caps; @@ -252,6 +254,24 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp) return 0; } +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, @@ -272,6 +292,9 @@ static void tdx_guest_init(Object *obj) object_property_add_uint64_ptr(obj, "attributes", &tdx->attributes, OBJ_PROP_FLAG_READWRITE); + 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) -- 2.39.5