diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/kvm/kvm.h | 5 | ||||
| -rw-r--r-- | drivers/kvm/vmx.c | 160 |
2 files changed, 94 insertions, 71 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index f6ee1892872..bb32383ddff 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -306,6 +306,11 @@ struct kvm_vcpu { char *guest_fx_image; int fpu_active; int guest_fpu_loaded; + struct vmx_host_state { + int loaded; + u16 fs_sel, gs_sel, ldt_sel; + int fs_gs_ldt_reload_needed; + } vmx_host_state; int mmio_needed; int mmio_read_completed; diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 49cadd31120..677b38c4444 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -237,6 +237,93 @@ static void vmcs_set_bits(unsigned long field, u32 mask) vmcs_writel(field, vmcs_readl(field) | mask); } +static void reload_tss(void) +{ +#ifndef CONFIG_X86_64 + + /* + * VT restores TR but not its size. Useless. + */ + struct descriptor_table gdt; + struct segment_descriptor *descs; + + get_gdt(&gdt); + descs = (void *)gdt.base; + descs[GDT_ENTRY_TSS].type = 9; /* available TSS */ + load_TR_desc(); +#endif +} + +static void vmx_save_host_state(struct kvm_vcpu *vcpu) +{ + struct vmx_host_state *hs = &vcpu->vmx_host_state; + + if (hs->loaded) + return; + + hs->loaded = 1; + /* + * Set host fs and gs selectors. Unfortunately, 22.2.3 does not + * allow segment selectors with cpl > 0 or ti == 1. + */ + hs->ldt_sel = read_ldt(); + hs->fs_gs_ldt_reload_needed = hs->ldt_sel; + hs->fs_sel = read_fs(); + if (!(hs->fs_sel & 7)) + vmcs_write16(HOST_FS_SELECTOR, hs->fs_sel); + else { + vmcs_write16(HOST_FS_SELECTOR, 0); + hs->fs_gs_ldt_reload_needed = 1; + } + hs->gs_sel = read_gs(); + if (!(hs->gs_sel & 7)) + vmcs_write16(HOST_GS_SELECTOR, hs->gs_sel); + else { + vmcs_write16(HOST_GS_SELECTOR, 0); + hs->fs_gs_ldt_reload_needed = 1; + } + +#ifdef CONFIG_X86_64 + vmcs_writel(HOST_FS_BASE, read_msr(MSR_FS_BASE)); + vmcs_writel(HOST_GS_BASE, read_msr(MSR_GS_BASE)); +#else + vmcs_writel(HOST_FS_BASE, segment_base(hs->fs_sel)); + vmcs_writel(HOST_GS_BASE, segment_base(hs->gs_sel)); +#endif +} + +static void vmx_load_host_state(struct kvm_vcpu *vcpu) +{ + struct vmx_host_state *hs = &vcpu->vmx_host_state; + + if (!hs->loaded) + return; + + hs->loaded = 0; + if (hs->fs_gs_ldt_reload_needed) { + load_ldt(hs->ldt_sel); + load_fs(hs->fs_sel); + /* + * If we have to reload gs, we must take care to + * preserve our gs base. + */ + local_irq_disable(); + load_gs(hs->gs_sel); +#ifdef CONFIG_X86_64 + wrmsrl(MSR_GS_BASE, vmcs_readl(HOST_GS_BASE)); +#endif + local_irq_enable(); + + reload_tss(); + } +#ifdef CONFIG_X86_64 + if (is_long_mode(vcpu)) { + save_msrs(vcpu->guest_msrs, NR_BAD_MSRS); + load_msrs(vcpu->host_msrs, NR_BAD_MSRS); + } +#endif +} + /* * Switches to specified vcpu, until a matching vcpu_put(), but assumes * vcpu mutex is already taken. @@ -283,6 +370,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu) static void vmx_vcpu_put(struct kvm_vcpu *vcpu) { + vmx_load_host_state(vcpu); kvm_put_guest_fpu(vcpu); put_cpu(); } @@ -397,23 +485,6 @@ static void guest_write_tsc(u64 guest_tsc) vmcs_write64(TSC_OFFSET, guest_tsc - host_tsc); } -static void reload_tss(void) -{ -#ifndef CONFIG_X86_64 - - /* - * VT restores TR but not its size. Useless. - */ - struct descriptor_table gdt; - struct segment_descriptor *descs; - - get_gdt(&gdt); - descs = (void *)gdt.base; - descs[GDT_ENTRY_TSS].type = 9; /* available TSS */ - load_TR_desc(); -#endif -} - /* * Reads an msr value (of 'msr_index') into 'pdata'. * Returns 0 on success, non-0 otherwise. @@ -1823,40 +1894,9 @@ static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu, static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { u8 fail; - u16 fs_sel, gs_sel, ldt_sel; - int fs_gs_ldt_reload_needed; int r; preempted: - /* - * Set host fs and gs selectors. Unfortunately, 22.2.3 does not - * allow segment selectors with cpl > 0 or ti == 1. - */ - ldt_sel = read_ldt(); - fs_gs_ldt_reload_needed = ldt_sel; - fs_sel = read_fs(); - if (!(fs_sel & 7)) - vmcs_write16(HOST_FS_SELECTOR, fs_sel); - else { - vmcs_write16(HOST_FS_SELECTOR, 0); - fs_gs_ldt_reload_needed = 1; - } - gs_sel = read_gs(); - if (!(gs_sel & 7)) - vmcs_write16(HOST_GS_SELECTOR, gs_sel); - else { - vmcs_write16(HOST_GS_SELECTOR, 0); - fs_gs_ldt_reload_needed = 1; - } - -#ifdef CONFIG_X86_64 - vmcs_writel(HOST_FS_BASE, read_msr(MSR_FS_BASE)); - vmcs_writel(HOST_GS_BASE, read_msr(MSR_GS_BASE)); -#else - vmcs_writel(HOST_FS_BASE, segment_base(fs_sel)); - vmcs_writel(HOST_GS_BASE, segment_base(gs_sel)); -#endif - if (!vcpu->mmio_read_completed) do_interrupt_requests(vcpu, kvm_run); @@ -1871,6 +1911,7 @@ preempted: #endif again: + vmx_save_host_state(vcpu); kvm_load_guest_fpu(vcpu); /* @@ -2040,29 +2081,6 @@ again: } out: - if (fs_gs_ldt_reload_needed) { - load_ldt(ldt_sel); - load_fs(fs_sel); - /* - * If we have to reload gs, we must take care to - * preserve our gs base. - */ - local_irq_disable(); - load_gs(gs_sel); -#ifdef CONFIG_X86_64 - wrmsrl(MSR_GS_BASE, vmcs_readl(HOST_GS_BASE)); -#endif - local_irq_enable(); - - reload_tss(); - } -#ifdef CONFIG_X86_64 - if (is_long_mode(vcpu)) { - save_msrs(vcpu->guest_msrs, NR_BAD_MSRS); - load_msrs(vcpu->host_msrs, NR_BAD_MSRS); - } -#endif - if (r > 0) { kvm_resched(vcpu); goto preempted; |