From a9f2705ec84449e3b8d70c804766f8e97e23080d Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Thu, 16 Dec 2021 10:19:36 +0800 Subject: [PATCH] KVM: VMX: Save HOST_CR3 in vmx_set_host_fs_gs() The host CR3 in the vcpu thread can only be changed when scheduling, so commit 15ad9762d69f ("KVM: VMX: Save HOST_CR3 in vmx_prepare_switch_to_guest()") changed vmx.c to only save it in vmx_prepare_switch_to_guest(). However, it also has to be synced in vmx_sync_vmcs_host_state() when switching VMCS. vmx_set_host_fs_gs() is called in both places, so rename it to vmx_set_vmcs_host_state() and make it update HOST_CR3. Fixes: 15ad9762d69f ("KVM: VMX: Save HOST_CR3 in vmx_prepare_switch_to_guest()") Signed-off-by: Lai Jiangshan Message-Id: <20211216021938.11752-2-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 3 ++- arch/x86/kvm/vmx/vmx.c | 20 +++++++++----------- arch/x86/kvm/vmx/vmx.h | 5 +++-- 3 files changed, 14 insertions(+), 14 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 2f6f465e575f..d07a7fa75783 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -245,7 +245,8 @@ static void vmx_sync_vmcs_host_state(struct vcpu_vmx *vmx, src = &prev->host_state; dest = &vmx->loaded_vmcs->host_state; - vmx_set_host_fs_gs(dest, src->fs_sel, src->gs_sel, src->fs_base, src->gs_base); + vmx_set_vmcs_host_state(dest, src->cr3, src->fs_sel, src->gs_sel, + src->fs_base, src->gs_base); dest->ldt_sel = src->ldt_sel; #ifdef CONFIG_X86_64 dest->ds_sel = src->ds_sel; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 9bf65e5e4840..ebf511f83903 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1069,9 +1069,14 @@ static void pt_guest_exit(struct vcpu_vmx *vmx) wrmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl); } -void vmx_set_host_fs_gs(struct vmcs_host_state *host, u16 fs_sel, u16 gs_sel, - unsigned long fs_base, unsigned long gs_base) +void vmx_set_vmcs_host_state(struct vmcs_host_state *host, unsigned long cr3, + u16 fs_sel, u16 gs_sel, + unsigned long fs_base, unsigned long gs_base) { + if (unlikely(cr3 != host->cr3)) { + vmcs_writel(HOST_CR3, cr3); + host->cr3 = cr3; + } if (unlikely(fs_sel != host->fs_sel)) { if (!(fs_sel & 7)) vmcs_write16(HOST_FS_SELECTOR, fs_sel); @@ -1103,7 +1108,6 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) #ifdef CONFIG_X86_64 int cpu = raw_smp_processor_id(); #endif - unsigned long cr3; unsigned long fs_base, gs_base; u16 fs_sel, gs_sel; int i; @@ -1167,14 +1171,8 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) gs_base = segment_base(gs_sel); #endif - vmx_set_host_fs_gs(host_state, fs_sel, gs_sel, fs_base, gs_base); - - /* Host CR3 including its PCID is stable when guest state is loaded. */ - cr3 = __get_current_cr3_fast(); - if (unlikely(cr3 != host_state->cr3)) { - vmcs_writel(HOST_CR3, cr3); - host_state->cr3 = cr3; - } + vmx_set_vmcs_host_state(host_state, __get_current_cr3_fast(), + fs_sel, gs_sel, fs_base, gs_base); vmx->guest_state_loaded = true; } diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 6c2c1aff1c3d..18111368cf85 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -371,8 +371,9 @@ int allocate_vpid(void); void free_vpid(int vpid); void vmx_set_constant_host_state(struct vcpu_vmx *vmx); void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu); -void vmx_set_host_fs_gs(struct vmcs_host_state *host, u16 fs_sel, u16 gs_sel, - unsigned long fs_base, unsigned long gs_base); +void vmx_set_vmcs_host_state(struct vmcs_host_state *host, unsigned long cr3, + u16 fs_sel, u16 gs_sel, + unsigned long fs_base, unsigned long gs_base); int vmx_get_cpl(struct kvm_vcpu *vcpu); bool vmx_emulation_required(struct kvm_vcpu *vcpu); unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu); -- 2.11.0