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charset="utf-8" Add x2apic emulation to WHPX for the kernel-irqchip=3Doff case. Unfortunately, it looks like there isn't a workaround available for proper behavior of PIC interrupts when kernel-irqchip=3Don for Windows 10. The OS is out of support outside of extended security updates so this will not be addressed. The performance boost is quite visible for multicore guests. Signed-off-by: Mohamed Mediouni --- target/i386/whpx/whpx-all.c | 134 +++++++++++++++++++++++++++++++++++- 1 file changed, 133 insertions(+), 1 deletion(-) diff --git a/target/i386/whpx/whpx-all.c b/target/i386/whpx/whpx-all.c index e56ae2b343..4127440c0c 100644 --- a/target/i386/whpx/whpx-all.c +++ b/target/i386/whpx/whpx-all.c @@ -1082,6 +1082,8 @@ HRESULT whpx_set_exception_exit_bitmap(UINT64 excepti= ons) /* Register for MSR and CPUID exits */ memset(&prop, 0, sizeof(WHV_PARTITION_PROPERTY)); prop.ExtendedVmExits.X64MsrExit =3D 1; + prop.ExtendedVmExits.X64CpuidExit =3D 1; + if (exceptions !=3D 0) { prop.ExtendedVmExits.ExceptionExit =3D 1; } @@ -1898,6 +1900,18 @@ int whpx_vcpu_run(CPUState *cpu) WHV_REGISTER_NAME reg_names[3]; UINT32 reg_count; bool is_known_msr =3D 0;=20 + uint64_t val; + + if (vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite) { + val =3D ((uint32_t)vcpu->exit_ctx.MsrAccess.Rax) | + ((uint64_t)(vcpu->exit_ctx.MsrAccess.Rdx) << 32); + } else { + /* + * Workaround for [-Werror=3Dmaybe-uninitialized] + * with GCC. Not needed with Clang. + */ + val =3D 0; + } =20 reg_names[0] =3D WHvX64RegisterRip; reg_names[1] =3D WHvX64RegisterRax; @@ -1911,7 +1925,47 @@ int whpx_vcpu_run(CPUState *cpu) && !vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite && !whpx_irqchip_in_kernel()) { is_known_msr =3D 1; - reg_values[1].Reg32 =3D (uint32_t)X86_CPU(cpu)->env.apic_b= us_freq; + val =3D X86_CPU(cpu)->env.apic_bus_freq; + } + + if (!whpx_irqchip_in_kernel() && + vcpu->exit_ctx.MsrAccess.MsrNumber =3D=3D MSR_IA32_APICBAS= E) { + is_known_msr =3D 1; + if (!vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite) { + /* Read path unreachable on Hyper-V */ + abort(); + } else { + WHV_REGISTER_VALUE reg =3D {.Reg64 =3D val}; + int msr_ret =3D cpu_set_apic_base(X86_CPU(cpu)->apic_s= tate, val); + if (msr_ret < 0) { + x86_emul_raise_exception(&X86_CPU(cpu)->env, EXCP0= D_GPF, 0); + } + whpx_set_reg(cpu, WHvX64RegisterApicBase, reg); + } + } + + if (!whpx_irqchip_in_kernel() && + vcpu->exit_ctx.MsrAccess.MsrNumber >=3D MSR_APIC_START && + vcpu->exit_ctx.MsrAccess.MsrNumber <=3D MSR_APIC_END) { + int index =3D vcpu->exit_ctx.MsrAccess.MsrNumber - MSR_API= C_START; + int msr_ret; + is_known_msr =3D 1; + if (!vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite) { + bql_lock(); + msr_ret =3D apic_msr_read(X86_CPU(cpu)->apic_state, in= dex, &val); + bql_unlock(); + reg_values[1].Reg64 =3D val; + if (msr_ret < 0) { + x86_emul_raise_exception(&X86_CPU(cpu)->env, EXCP0= D_GPF, 0); + } + } else { + bql_lock(); + msr_ret =3D apic_msr_write(X86_CPU(cpu)->apic_state, i= ndex, val); + bql_unlock(); + if (msr_ret < 0) { + x86_emul_raise_exception(&X86_CPU(cpu)->env, EXCP0= D_GPF, 0); + } + } } /* * For all unsupported MSR access we: @@ -1921,6 +1975,11 @@ int whpx_vcpu_run(CPUState *cpu) reg_count =3D vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite ? 1 : 3; =20 + if (!vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite) { + reg_values[1].Reg32 =3D (uint32_t)val; + reg_values[2].Reg32 =3D (uint32_t)(val >> 32); + } + if (!is_known_msr) { trace_whpx_unsupported_msr_access(vcpu->exit_ctx.MsrAccess= .MsrNumber, vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite); @@ -1939,6 +1998,47 @@ int whpx_vcpu_run(CPUState *cpu) ret =3D 0; break; } + case WHvRunVpExitReasonX64Cpuid: { + WHV_REGISTER_VALUE reg_values[5] =3D {0}; + WHV_REGISTER_NAME reg_names[5]; + UINT32 reg_count =3D 5; + X86CPU *x86_cpu =3D X86_CPU(cpu); + CPUX86State *env =3D &x86_cpu->env; + + reg_names[0] =3D WHvX64RegisterRip; + reg_names[1] =3D WHvX64RegisterRax; + reg_names[2] =3D WHvX64RegisterRcx; + reg_names[3] =3D WHvX64RegisterRdx; + reg_names[4] =3D WHvX64RegisterRbx; + + reg_values[0].Reg64 =3D + vcpu->exit_ctx.VpContext.Rip + + vcpu->exit_ctx.VpContext.InstructionLength; + + reg_values[1].Reg64 =3D vcpu->exit_ctx.CpuidAccess.DefaultResu= ltRax; + reg_values[2].Reg64 =3D vcpu->exit_ctx.CpuidAccess.DefaultResu= ltRcx; + reg_values[3].Reg64 =3D vcpu->exit_ctx.CpuidAccess.DefaultResu= ltRdx; + reg_values[4].Reg64 =3D vcpu->exit_ctx.CpuidAccess.DefaultResu= ltRbx; + + if (vcpu->exit_ctx.CpuidAccess.Rax =3D=3D 1) { + if (cpu_has_x2apic_feature(env)) { + reg_values[2].Reg64 |=3D CPUID_EXT_X2APIC; + } + } + + hr =3D whp_dispatch.WHvSetVirtualProcessorRegisters( + whpx->partition, + cpu->cpu_index, + reg_names, reg_count, + reg_values); + + if (FAILED(hr)) { + error_report("WHPX: Failed to set CpuidAccess state " + " registers, hr=3D%08lx", hr); + } + ret =3D 0; + break; + } case WHvRunVpExitReasonException: whpx_get_registers(cpu, WHPX_LEVEL_FULL_STATE); =20 @@ -2136,6 +2236,7 @@ int whpx_accel_init(AccelState *as, MachineState *ms) WHV_PROCESSOR_FEATURES_BANKS processor_features; WHV_PROCESSOR_PERFMON_FEATURES perfmon_features; bool is_legacy_os =3D false; + UINT32 cpuidExitList[] =3D {1}; =20 whpx =3D &whpx_global; =20 @@ -2354,6 +2455,7 @@ int whpx_accel_init(AccelState *as, MachineState *ms) /* Register for MSR and CPUID exits */ memset(&prop, 0, sizeof(WHV_PARTITION_PROPERTY)); prop.ExtendedVmExits.X64MsrExit =3D 1; + prop.ExtendedVmExits.X64CpuidExit =3D 1; =20 hr =3D whp_dispatch.WHvSetPartitionProperty( whpx->partition, @@ -2366,6 +2468,36 @@ int whpx_accel_init(AccelState *as, MachineState *ms) goto error; } =20 + memset(&prop, 0, sizeof(WHV_PARTITION_PROPERTY)); + prop.X64MsrExitBitmap.UnhandledMsrs =3D 1; + if (!whpx_irqchip_in_kernel()) { + prop.X64MsrExitBitmap.ApicBaseMsrWrite =3D 1; + } + + hr =3D whp_dispatch.WHvSetPartitionProperty( + whpx->partition, + WHvPartitionPropertyCodeX64MsrExitBitmap, + &prop, + sizeof(WHV_PARTITION_PROPERTY)); + if (FAILED(hr)) { + error_report("WHPX: Failed to set MSR exit bitmap, hr=3D%08lx", hr= ); + ret =3D -EINVAL; + goto error; + } + + hr =3D whp_dispatch.WHvSetPartitionProperty( + whpx->partition, + WHvPartitionPropertyCodeCpuidExitList, + cpuidExitList, + RTL_NUMBER_OF(cpuidExitList) * sizeof(UINT32)); + + if (FAILED(hr)) { + error_report("WHPX: Failed to set partition CpuidExitList hr=3D%08= lx", + hr); + ret =3D -EINVAL; + goto error; + } + /* * We do not want to intercept any exceptions from the guest, * until we actually start debugging with gdb. --=20 2.50.1 (Apple Git-155)