cpuid: Entries can now be retreived from kvm

These represent what a guest VM can see for features.

Cargo.toml

@@ -11,7 +11,10 @@ structopt = "0.3"
 serde = { version = "1.0", features = ["derive"] }
 serde_yaml = "0.8"
 enum_dispatch = "0.3.8"
+kvm-ioctls = { version = "0.12.0", optional = true }
+kvm-bindings = { version = "0.6.0", features = ["fam-wrappers"], optional = true }
 
 [features]
-default = ["use_msr"]
+default = ["use_msr", "kvm"]
 use_msr = []
+kvm = [ "dep:kvm-ioctls", "dep:kvm-bindings" ]

src/layout.rs

@@ -3,18 +3,23 @@
 use super::facts::{self, GenericFact};
 use super::{
     bitfield::{self, Facter},
-    cpuid, is_empty_leaf,
+    is_empty_leaf,
 };
 use core::arch::x86_64::CpuidResult;
 use enum_dispatch::enum_dispatch;
 use serde::{Deserialize, Serialize};
 use std::fmt;
+use std::ops::Fn;
 use std::string;
 use std::vec::Vec;
 
 #[enum_dispatch]
 pub trait DisplayLeaf {
-    fn scan_sub_leaves(&self, leaf: u32) -> Vec<CpuidResult>;
+    fn scan_sub_leaves<CPUIDFunc: Fn(u32, u32) -> CpuidResult>(
+        &self,
+        leaf: u32,
+        cpuid: CPUIDFunc,
+    ) -> Vec<CpuidResult>;
     fn display_leaf(
         &self,
         leaf: &[CpuidResult],
@@ -48,7 +53,11 @@ impl StartLeaf {
 }
 
 impl DisplayLeaf for StartLeaf {
-    fn scan_sub_leaves(&self, leaf: u32) -> Vec<CpuidResult> {
+    fn scan_sub_leaves<CPUIDFunc: Fn(u32, u32) -> CpuidResult>(
+        &self,
+        leaf: u32,
+        cpuid: CPUIDFunc,
+    ) -> Vec<CpuidResult> {
         vec![cpuid(leaf, 0)]
     }
     fn display_leaf(
@@ -104,7 +113,11 @@ impl StringLeaf {
 }
 
 impl DisplayLeaf for StringLeaf {
-    fn scan_sub_leaves(&self, leaf: u32) -> Vec<CpuidResult> {
+    fn scan_sub_leaves<CPUIDFunc: Fn(u32, u32) -> CpuidResult>(
+        &self,
+        leaf: u32,
+        cpuid: CPUIDFunc,
+    ) -> Vec<CpuidResult> {
         let cpuid = cpuid(leaf, 0);
         if !is_empty_leaf(&cpuid) {
             vec![cpuid]
@@ -159,7 +172,11 @@ impl BitFieldLeaf {
 }
 
 impl DisplayLeaf for BitFieldLeaf {
-    fn scan_sub_leaves(&self, leaf: u32) -> Vec<CpuidResult> {
+    fn scan_sub_leaves<CPUIDFunc: Fn(u32, u32) -> CpuidResult>(
+        &self,
+        leaf: u32,
+        cpuid: CPUIDFunc,
+    ) -> Vec<CpuidResult> {
         let cpuid = cpuid(leaf, 0);
         if !is_empty_leaf(&cpuid) {
             vec![cpuid]
@@ -232,8 +249,12 @@ impl LeafDesc {
         &self.data_type
     }
 
-    pub fn bind_leaf(&self, leaf: u32) -> Option<BoundLeaf> {
-        let sub_leaves = self.scan_sub_leaves(leaf);
+    pub fn bind_leaf<CPUIDFunc: Fn(u32, u32) -> CpuidResult>(
+        &self,
+        leaf: u32,
+        cpuid: CPUIDFunc,
+    ) -> Option<BoundLeaf> {
+        let sub_leaves = self.scan_sub_leaves(leaf, cpuid);
         if !sub_leaves.is_empty() {
             Some(BoundLeaf {
                 desc: self,
@@ -246,8 +267,12 @@ impl LeafDesc {
 }
 
 impl DisplayLeaf for LeafDesc {
-    fn scan_sub_leaves(&self, leaf: u32) -> Vec<CpuidResult> {
-        self.data_type.scan_sub_leaves(leaf)
+    fn scan_sub_leaves<CPUIDFunc: Fn(u32, u32) -> CpuidResult>(
+        &self,
+        leaf: u32,
+        cpuid: CPUIDFunc,
+    ) -> Vec<CpuidResult> {
+        self.data_type.scan_sub_leaves(leaf, cpuid)
     }
     fn display_leaf(
         &self,

src/lib.rs

@@ -24,7 +24,7 @@ impl std::fmt::Display for CpuidError {
 
 impl std::error::Error for CpuidError {}
 
-fn cpuid(leaf: u32, sub_leaf: u32) -> CpuidResult {
+pub fn cpuid(leaf: u32, sub_leaf: u32) -> CpuidResult {
     unsafe { __cpuid_count(leaf, sub_leaf) }
 }
 

src/main.rs

@@ -47,11 +47,57 @@ impl Command for Disp {
         } else {
             println!("CPUID:");
             for (leaf, desc) in &config.cpuids {
-                if let Some(bound) = desc.bind_leaf(*leaf) {
+                if let Some(bound) = desc.bind_leaf(*leaf, cpuid) {
                     println!("{:#010x}: {}", leaf, bound);
                 }
             }
 
+            #[cfg(all(target_os = "linux", feature = "kvm"))]
+            {
+                use kvm_bindings::{KVM_CPUID_FLAG_SIGNIFCANT_INDEX, KVM_MAX_CPUID_ENTRIES};
+                use kvm_ioctls::Kvm;
+                println!("KVM-CPUID:");
+                let kvm = Kvm::new().expect("Unable to open KVM");
+                let cpuid_fam = kvm
+                    .get_supported_cpuid(KVM_MAX_CPUID_ENTRIES)
+                    .expect("Unable to retreive cpuid entries");
+                let cpuid_entries = cpuid_fam.as_slice();
+                for (leaf, desc) in &config.cpuids {
+                    use core::arch::x86_64::CpuidResult;
+                    if let Some(bound) = desc.bind_leaf(*leaf, |leaf, subleaf| {
+                        cpuid_entries
+                            .iter()
+                            .find_map(|entry| {
+                                if entry.function == leaf {
+                                    if (subleaf == 0
+                                        && (entry.flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) == 0)
+                                        || (subleaf == entry.index)
+                                    {
+                                        Some(CpuidResult {
+                                            eax: entry.eax,
+                                            ebx: entry.ebx,
+                                            ecx: entry.ecx,
+                                            edx: entry.edx,
+                                        })
+                                    } else {
+                                        None
+                                    }
+                                } else {
+                                    None
+                                }
+                            })
+                            .unwrap_or(CpuidResult {
+                                eax: 0,
+                                ebx: 0,
+                                ecx: 0,
+                                edx: 0,
+                            })
+                    }) {
+                        println!("{:#010x}: {}", leaf, bound);
+                    }
+                }
+            }
+
             if MSRDesc::is_availible() {
                 println!("MSRS:");
                 for msr in &config.msrs {
@@ -73,7 +119,7 @@ fn collect_facts(config: &Definition) -> Result<Vec<YAMLFact>, Box<dyn std::erro
     let mut ret: Vec<YAMLFact> = config
         .cpuids
         .iter()
-        .filter_map(|(leaf, desc)| desc.bind_leaf(*leaf))
+        .filter_map(|(leaf, desc)| desc.bind_leaf(*leaf, cpuid))
         .flat_map(|bound| bound.get_facts().into_iter())
         .map(|mut fact| {
             fact.add_path("cpuid");