From 57e3ada3e552dcd2de7e22acfb6eac2000f98868 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Wed, 20 Jun 2018 13:58:37 -0400 Subject: [PATCH] x86/KVM/VMX: Split the VMX MSR LOAD structures to have an host/guest numbers commit 33966dd6b2d2c352fae55412db2ea8cfff5df13a upstream There is no semantic change but this change allows an unbalanced amount of MSRs to be loaded on VMEXIT and VMENTER, i.e. the number of MSRs to save or restore on VMEXIT or VMENTER may be different. Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Thomas Gleixner Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx.c | 65 +++++++++++++++++++++++++++++------------------------- 1 file changed, 35 insertions(+), 30 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 1b24d15..6cced1da 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -592,6 +592,11 @@ static inline int pi_test_sn(struct pi_desc *pi_desc) (unsigned long *)&pi_desc->control); } +struct vmx_msrs { + unsigned int nr; + struct vmx_msr_entry val[NR_AUTOLOAD_MSRS]; +}; + struct vcpu_vmx { struct kvm_vcpu vcpu; unsigned long host_rsp; @@ -624,9 +629,8 @@ struct vcpu_vmx { struct loaded_vmcs *loaded_vmcs; bool __launched; /* temporary, used in vmx_vcpu_run */ struct msr_autoload { - unsigned nr; - struct vmx_msr_entry guest[NR_AUTOLOAD_MSRS]; - struct vmx_msr_entry host[NR_AUTOLOAD_MSRS]; + struct vmx_msrs guest; + struct vmx_msrs host; } msr_autoload; struct { int loaded; @@ -1994,18 +1998,18 @@ static void clear_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr) } break; } - - for (i = 0; i < m->nr; ++i) - if (m->guest[i].index == msr) + for (i = 0; i < m->guest.nr; ++i) + if (m->guest.val[i].index == msr) break; - if (i == m->nr) + if (i == m->guest.nr) return; - --m->nr; - m->guest[i] = m->guest[m->nr]; - m->host[i] = m->host[m->nr]; - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->nr); - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->nr); + --m->guest.nr; + --m->host.nr; + m->guest.val[i] = m->guest.val[m->guest.nr]; + m->host.val[i] = m->host.val[m->host.nr]; + vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->guest.nr); + vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->host.nr); } static void add_atomic_switch_msr_special(struct vcpu_vmx *vmx, @@ -2057,24 +2061,25 @@ static void add_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr, wrmsrl(MSR_IA32_PEBS_ENABLE, 0); } - for (i = 0; i < m->nr; ++i) - if (m->guest[i].index == msr) + for (i = 0; i < m->guest.nr; ++i) + if (m->guest.val[i].index == msr) break; if (i == NR_AUTOLOAD_MSRS) { printk_once(KERN_WARNING "Not enough msr switch entries. " "Can't add msr %x\n", msr); return; - } else if (i == m->nr) { - ++m->nr; - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->nr); - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->nr); + } else if (i == m->guest.nr) { + ++m->guest.nr; + ++m->host.nr; + vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->guest.nr); + vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->host.nr); } - m->guest[i].index = msr; - m->guest[i].value = guest_val; - m->host[i].index = msr; - m->host[i].value = host_val; + m->guest.val[i].index = msr; + m->guest.val[i].value = guest_val; + m->host.val[i].index = msr; + m->host.val[i].value = host_val; } static void reload_tss(void) @@ -5316,9 +5321,9 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx) vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0); vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0); - vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host)); + vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host.val)); vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, 0); - vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest)); + vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest.val)); if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat); @@ -10224,10 +10229,10 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) * Set the MSR load/store lists to match L0's settings. */ vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0); - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.nr); - vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host)); - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.nr); - vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest)); + vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr); + vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host.val)); + vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.guest.nr); + vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest.val)); /* * HOST_RSP is normally set correctly in vmx_vcpu_run() just before @@ -11076,8 +11081,8 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason, load_vmcs12_host_state(vcpu, vmcs12); /* Update any VMCS fields that might have changed while L2 ran */ - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.nr); - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.nr); + vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr); + vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.guest.nr); vmcs_write64(TSC_OFFSET, vcpu->arch.tsc_offset); if (vmx->hv_deadline_tsc == -1) vmcs_clear_bits(PIN_BASED_VM_EXEC_CONTROL, -- 2.7.4