[PATCH v2 2/5] hvf: remove TSC synchronization code because it isn't fully complete

[Cameron Esfahani]

The existing code in QEMU's HVF support to attempt to synchronize TSC
across multiple cores is not sufficient.  TSC value on other cores
can go backwards.  Until implementation is fixed, remove calls to
hv_vm_sync_tsc().  Pass through TSC to guest OS.

Signed-off-by: Cameron Esfahani <address@hidden>
---
 target/i386/hvf/hvf.c     | 3 +--
 target/i386/hvf/x86_emu.c | 3 ---
 target/i386/hvf/x86hvf.c  | 4 ----
 3 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/target/i386/hvf/hvf.c b/target/i386/hvf/hvf.c
index 0b50cfcbc6..90fd50acfc 100644
--- a/target/i386/hvf/hvf.c
+++ b/target/i386/hvf/hvf.c
@@ -518,7 +518,6 @@ void hvf_reset_vcpu(CPUState *cpu) {
         wreg(cpu->hvf_fd, HV_X86_R8 + i, 0x0);
     }
 
-    hv_vm_sync_tsc(0);
     hv_vcpu_invalidate_tlb(cpu->hvf_fd);
     hv_vcpu_flush(cpu->hvf_fd);
 }
@@ -612,7 +611,7 @@ int hvf_init_vcpu(CPUState *cpu)
     hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_GSBASE, 1);
     hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_KERNELGSBASE, 1);
     hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_TSC_AUX, 1);
-    /*hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_IA32_TSC, 1);*/
+    hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_IA32_TSC, 1);
     hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_IA32_SYSENTER_CS, 1);
     hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_IA32_SYSENTER_EIP, 1);
     hv_vcpu_enable_native_msr(cpu->hvf_fd, MSR_IA32_SYSENTER_ESP, 1);
diff --git a/target/i386/hvf/x86_emu.c b/target/i386/hvf/x86_emu.c
index 1b04bd7e94..3df767209d 100644
--- a/target/i386/hvf/x86_emu.c
+++ b/target/i386/hvf/x86_emu.c
@@ -772,9 +772,6 @@ void simulate_wrmsr(struct CPUState *cpu)
 
     switch (msr) {
     case MSR_IA32_TSC:
-        /* if (!osx_is_sierra())
-             wvmcs(cpu->hvf_fd, VMCS_TSC_OFFSET, data - rdtscp());
-        hv_vm_sync_tsc(data);*/
         break;
     case MSR_IA32_APICBASE:
         cpu_set_apic_base(X86_CPU(cpu)->apic_state, data);
diff --git a/target/i386/hvf/x86hvf.c b/target/i386/hvf/x86hvf.c
index e0ea02d631..1485b95776 100644
--- a/target/i386/hvf/x86hvf.c
+++ b/target/i386/hvf/x86hvf.c
@@ -152,10 +152,6 @@ void hvf_put_msrs(CPUState *cpu_state)
 
     hv_vcpu_write_msr(cpu_state->hvf_fd, MSR_GSBASE, env->segs[R_GS].base);
     hv_vcpu_write_msr(cpu_state->hvf_fd, MSR_FSBASE, env->segs[R_FS].base);
-
-    /* if (!osx_is_sierra())
-         wvmcs(cpu_state->hvf_fd, VMCS_TSC_OFFSET, env->tsc - rdtscp());*/
-    hv_vm_sync_tsc(env->tsc);
 }
 
 
-- 
2.24.0