| Message ID | 20240309012725.1409949-7-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86/cpu: KVM: Clean up PAT and VMX macros | expand |
On Fri, Mar 08, 2024 at 05:27:22PM -0800, Sean Christopherson wrote: > Date: Fri, 8 Mar 2024 17:27:22 -0800 > From: Sean Christopherson <seanjc@google.com> > Subject: [PATCH v6 6/9] KVM: nVMX: Use macros and #defines in > vmx_restore_vmx_basic() > X-Mailer: git-send-email 2.44.0.278.ge034bb2e1d-goog > > From: Xin Li <xin3.li@intel.com> > > Use macros in vmx_restore_vmx_basic() instead of open coding everything > using BIT_ULL() and GENMASK_ULL(). Opportunistically split feature bits > and reserved bits into separate variables, and add a comment explaining > the subset logic (it's not immediately obvious that the set of feature > bits is NOT the set of _supported_ feature bits). > > Cc: Shan Kang <shan.kang@intel.com> > Cc: Kai Huang <kai.huang@intel.com> > Signed-off-by: Xin Li <xin3.li@intel.com> > [sean: split to separate patch, write changelog, drop #defines] > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > arch/x86/kvm/vmx/nested.c | 25 ++++++++++++++++++------- > 1 file changed, 18 insertions(+), 7 deletions(-) Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
On Fri, 2024-03-08 at 17:27 -0800, Sean Christopherson wrote: > From: Xin Li <xin3.li@intel.com> > > Use macros in vmx_restore_vmx_basic() instead of open coding everything > using BIT_ULL() and GENMASK_ULL(). Opportunistically split feature bits > and reserved bits into separate variables, and add a comment explaining > the subset logic (it's not immediately obvious that the set of feature > bits is NOT the set of _supported_ feature bits). > > Cc: Shan Kang <shan.kang@intel.com> > Cc: Kai Huang <kai.huang@intel.com> > Signed-off-by: Xin Li <xin3.li@intel.com> > [sean: split to separate patch, write changelog, drop #defines] > Signed-off-by: Sean Christopherson <seanjc@google.com> > Reviewed-by: Kai Huang <kai.huang@intel.com>
On 3/9/2024 9:27 AM, Sean Christopherson wrote: > From: Xin Li <xin3.li@intel.com> > > Use macros in vmx_restore_vmx_basic() instead of open coding everything > using BIT_ULL() and GENMASK_ULL(). Opportunistically split feature bits > and reserved bits into separate variables, and add a comment explaining > the subset logic (it's not immediately obvious that the set of feature > bits is NOT the set of _supported_ feature bits). > > Cc: Shan Kang <shan.kang@intel.com> > Cc: Kai Huang <kai.huang@intel.com> > Signed-off-by: Xin Li <xin3.li@intel.com> > [sean: split to separate patch, write changelog, drop #defines] > Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> > --- > arch/x86/kvm/vmx/nested.c | 25 ++++++++++++++++++------- > 1 file changed, 18 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > index 82a35aba7d2b..4ad8696c25af 100644 > --- a/arch/x86/kvm/vmx/nested.c > +++ b/arch/x86/kvm/vmx/nested.c > @@ -1228,21 +1228,32 @@ static bool is_bitwise_subset(u64 superset, u64 subset, u64 mask) > > static int vmx_restore_vmx_basic(struct vcpu_vmx *vmx, u64 data) > { > - const u64 feature_and_reserved = > - /* feature (except bit 48; see below) */ > - BIT_ULL(49) | BIT_ULL(54) | BIT_ULL(55) | > - /* reserved */ > - BIT_ULL(31) | GENMASK_ULL(47, 45) | GENMASK_ULL(63, 56); > + const u64 feature_bits = VMX_BASIC_DUAL_MONITOR_TREATMENT | > + VMX_BASIC_INOUT | > + VMX_BASIC_TRUE_CTLS; > + > + const u64 reserved_bits = GENMASK_ULL(63, 56) | > + GENMASK_ULL(47, 45) | > + BIT_ULL(31); > + > u64 vmx_basic = vmcs_config.nested.basic; > > - if (!is_bitwise_subset(vmx_basic, data, feature_and_reserved)) > + BUILD_BUG_ON(feature_bits & reserved_bits); > + > + /* > + * Except for 32BIT_PHYS_ADDR_ONLY, which is an anti-feature bit (has > + * inverted polarity), the incoming value must not set feature bits or > + * reserved bits that aren't allowed/supported by KVM. Fields, i.e. > + * multi-bit values, are explicitly checked below. > + */ > + if (!is_bitwise_subset(vmx_basic, data, feature_bits | reserved_bits)) > return -EINVAL; > > /* > * KVM does not emulate a version of VMX that constrains physical > * addresses of VMX structures (e.g. VMCS) to 32-bits. > */ > - if (data & BIT_ULL(48)) > + if (data & VMX_BASIC_32BIT_PHYS_ADDR_ONLY) > return -EINVAL; > > if (vmx_basic_vmcs_revision_id(vmx_basic) !=
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 82a35aba7d2b..4ad8696c25af 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -1228,21 +1228,32 @@ static bool is_bitwise_subset(u64 superset, u64 subset, u64 mask) static int vmx_restore_vmx_basic(struct vcpu_vmx *vmx, u64 data) { - const u64 feature_and_reserved = - /* feature (except bit 48; see below) */ - BIT_ULL(49) | BIT_ULL(54) | BIT_ULL(55) | - /* reserved */ - BIT_ULL(31) | GENMASK_ULL(47, 45) | GENMASK_ULL(63, 56); + const u64 feature_bits = VMX_BASIC_DUAL_MONITOR_TREATMENT | + VMX_BASIC_INOUT | + VMX_BASIC_TRUE_CTLS; + + const u64 reserved_bits = GENMASK_ULL(63, 56) | + GENMASK_ULL(47, 45) | + BIT_ULL(31); + u64 vmx_basic = vmcs_config.nested.basic; - if (!is_bitwise_subset(vmx_basic, data, feature_and_reserved)) + BUILD_BUG_ON(feature_bits & reserved_bits); + + /* + * Except for 32BIT_PHYS_ADDR_ONLY, which is an anti-feature bit (has + * inverted polarity), the incoming value must not set feature bits or + * reserved bits that aren't allowed/supported by KVM. Fields, i.e. + * multi-bit values, are explicitly checked below. + */ + if (!is_bitwise_subset(vmx_basic, data, feature_bits | reserved_bits)) return -EINVAL; /* * KVM does not emulate a version of VMX that constrains physical * addresses of VMX structures (e.g. VMCS) to 32-bits. */ - if (data & BIT_ULL(48)) + if (data & VMX_BASIC_32BIT_PHYS_ADDR_ONLY) return -EINVAL; if (vmx_basic_vmcs_revision_id(vmx_basic) !=