Cpuid vm exit support

gamozolabs · Aug 26, 2020 · 127a9ec · 127a9ec
1 parent 54d971c
commit 127a9ec
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Showing 2 changed files with 25 additions and 0 deletions.
diff --git a/kernel/src/fuzz_session.rs b/kernel/src/fuzz_session.rs
@@ -987,6 +987,24 @@ impl<'a> Worker<'a> {
             self.stats.vm_cycles += vm_cycles;
 
             match vmexit {
+                VmExit::CpuId { inst_len } => {
+                    let rax = self.reg(Register::Rax) as u32;
+                    let rcx = self.reg(Register::Rcx) as u32;
+
+                    // Take the host cpuid and write it into the guest
+                    unsafe{
+                        let (eax, ebx, ecx, edx) = cpu::cpuid(rax,rcx);
+                        self.set_reg(Register::Eax, eax as u64);
+                        self.set_reg(Register::Ebx, ebx as u64);
+                        self.set_reg(Register::Ecx, ecx as u64);
+                        self.set_reg(Register::Edx, edx as u64);
+                    }
+
+                    // Advance RIP to next instruction
+                    let rip = self.reg(Register::Rip);
+                    self.set_reg(Register::Rip, rip.wrapping_add(inst_len));
+                    continue 'vm_loop;
+                }
                 VmExit::Rdtsc { inst_len } => {
                     let tsc = self.backing.vm.guest_regs.tsc;
                     self.set_reg(Register::Rax, (tsc >>  0) & 0xffffffff);

diff --git a/kernel/src/vtx.rs b/kernel/src/vtx.rs
@@ -1141,6 +1141,9 @@ pub enum CpuMode {
 /// Virtual machine exit reason
 #[derive(Debug, Clone, Copy, PartialOrd, Ord, PartialEq, Eq)]
 pub enum VmExit {
+    CpuId {
+        inst_len: u64,
+    },
     VmCall,
     InterruptWindow,
     Io,
@@ -1954,6 +1957,10 @@ impl Vm {
             }
             1 => VmExit::ExternalInterrupt,
             7 => VmExit::InterruptWindow,
+            10 => {
+                let inst_len = self.reg(Register::ExitInstructionLength);
+                VmExit::CpuId { inst_len }
+            }
             16 => {
                 let inst_len = self.reg(Register::ExitInstructionLength);
                 VmExit::Rdtsc { inst_len }