1 files changed, 89 insertions, 71 deletions

diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index 49cadd31120b..677b38c4444a 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;