kvm: x86: Adjust PC to remove the CS segment base address

gem5 seems to store the PC as RIP+CS_BASE. This is not what KVM
expects, so we need to subtract CS_BASE prior to transferring the PC
into KVM. This changeset adds the necessary PC manipulation and
refactors thread context updates slightly to avoid reading registers
multiple times from KVM.

--HG--
extra : rebase_source : 3f0569dca06a1fcd8694925f75c8918d954ada44

1 files changed, 5 insertions, 4 deletions

diff --git a/src/cpu/kvm/x86_cpu.hh b/src/cpu/kvm/x86_cpu.hh
index 7dacdb03f..bfd090ff7 100644
--- a/src/cpu/kvm/x86_cpu.hh
+++ b/src/cpu/kvm/x86_cpu.hh
@@ -209,13 +209,14 @@ class X86KvmCPU : public BaseKvmCPU
      * @{
      */
     /** Update integer registers */
-    void updateThreadContextRegs();
+    void updateThreadContextRegs(const struct kvm_regs &regs,
+                                 const struct kvm_sregs &sregs);
     /** Update control registers (CRx, segments, etc.) */
-    void updateThreadContextSRegs();
+    void updateThreadContextSRegs(const struct kvm_sregs &sregs);
     /** Update FPU and SIMD registers using the legacy API */
-    void updateThreadContextFPU();
+    void updateThreadContextFPU(const struct kvm_fpu &fpu);
     /** Update FPU and SIMD registers using the XSave API */
-    void updateThreadContextXSave();
+    void updateThreadContextXSave(const struct kvm_xsave &kxsave);
     /** Update MSR registers */
     void updateThreadContextMSRs();
     /** @} */