On 10/12/2017 21:30, Luwei Kang wrote:
> From: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
>
> Load/Store Intel processor trace register in context switch.
> MSR IA32_RTIT_CTL is loaded/stored automatically from VMCS.
> In HOST mode, we just need to restore the status of IA32_RTIT_CTL.
> In HOST_GUEST mode, we need load/resore PT MSRs only when PT is
> enabled in guest.
>
> Signed-off-by: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
> Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
> ---
> arch/x86/kvm/vmx.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 61 insertions(+)
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index f948231..d45cc76 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -2144,6 +2144,55 @@ static unsigned long segment_base(u16 selector)
> }
> #endif
>
> +static inline void pt_load_msr(struct pt_ctx *ctx, unsigned int addr_num)
> +{
> + u32 i;
> +
> + wrmsrl(MSR_IA32_RTIT_STATUS, ctx->status);
> + wrmsrl(MSR_IA32_RTIT_OUTPUT_BASE, ctx->output_base);
> + wrmsrl(MSR_IA32_RTIT_OUTPUT_MASK, ctx->output_mask);
> + wrmsrl(MSR_IA32_RTIT_CR3_MATCH, ctx->cr3_match);
> + for (i = 0; i < addr_num; i++)
> + wrmsrl(MSR_IA32_RTIT_ADDR0_A + i, ctx->addrs[i]);
> +}
> +
> +static inline void pt_save_msr(struct pt_ctx *ctx, unsigned int addr_num)
> +{
> + u32 i;
> +
> + rdmsrl(MSR_IA32_RTIT_STATUS, ctx->status);
> + rdmsrl(MSR_IA32_RTIT_OUTPUT_BASE, ctx->output_base);
> + rdmsrl(MSR_IA32_RTIT_OUTPUT_MASK, ctx->output_mask);
> + rdmsrl(MSR_IA32_RTIT_CR3_MATCH, ctx->cr3_match);
> + for (i = 0; i < addr_num; i++)
> + rdmsrl(MSR_IA32_RTIT_ADDR0_A + i, ctx->addrs[i]);
> +}
> +
> +static void pt_guest_enter(struct vcpu_vmx *vmx)
> +{
> + if (pt_mode == PT_MODE_HOST || PT_MODE_HOST_GUEST)
Small mistake here (missing "pt_mode == ").
Thanks,
Paolo
> + rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
> +
> + if (pt_mode == PT_MODE_HOST_GUEST &&
> + vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
> + wrmsrl(MSR_IA32_RTIT_CTL, 0);
> + pt_save_msr(&vmx->pt_desc.host, vmx->pt_desc.addr_num);
> + pt_load_msr(&vmx->pt_desc.guest, vmx->pt_desc.addr_num);
> + }
> +}
> +
> +static void pt_guest_exit(struct vcpu_vmx *vmx)
> +{
> + if (pt_mode == PT_MODE_HOST_GUEST &&
> + vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
> + pt_save_msr(&vmx->pt_desc.guest, vmx->pt_desc.addr_num);
> + pt_load_msr(&vmx->pt_desc.host, vmx->pt_desc.addr_num);
> + }
> +
> + if (pt_mode == PT_MODE_HOST || pt_mode == PT_MODE_HOST_GUEST)
> + wrmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
> +}
> +
> static void vmx_save_host_state(struct kvm_vcpu *vcpu)
> {
> struct vcpu_vmx *vmx = to_vmx(vcpu);
> @@ -5766,6 +5815,14 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx)
> vmcs_write64(PML_ADDRESS, page_to_phys(vmx->pml_pg));
> vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1);
> }
> +
> + if (pt_mode == PT_MODE_HOST_GUEST) {
> + memset(&vmx->pt_desc, 0, sizeof(vmx->pt_desc));
> + vmx->pt_desc.addr_num = kvm_get_pt_addr_cnt();
> + /* Bit[6~0] are forced to 1, writes are ignored. */
> + vmx->pt_desc.guest.output_mask = 0x7F;
> + vmcs_write64(GUEST_IA32_RTIT_CTL, 0);
> + }
> }
>
> static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> @@ -9589,6 +9646,8 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
> vcpu->arch.pkru != vmx->host_pkru)
> __write_pkru(vcpu->arch.pkru);
>
> + pt_guest_enter(vmx);
> +
> atomic_switch_perf_msrs(vmx);
> debugctlmsr = get_debugctlmsr();
>
> @@ -9724,6 +9783,8 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
> | (1 << VCPU_EXREG_CR3));
> vcpu->arch.regs_dirty = 0;
>
> + pt_guest_exit(vmx);
> +
> /*
> * eager fpu is enabled if PKEY is supported and CR4 is switched
> * back on host, so it is safe to read guest PKRU from current
>
