KVM: Correct ordering of ldt reload wrt fs/gs reload
authorAvi Kivity <avi@redhat.com>
Tue, 19 Oct 2010 16:48:35 +0000 (18:48 +0200)
committerMarcelo Tosatti <mtosatti@redhat.com>
Wed, 17 Nov 2010 21:47:59 +0000 (19:47 -0200)
If fs or gs refer to the ldt, they must be reloaded after the ldt.  Reorder
the code to that effect.

Userspace code that uses the ldt with kvm is nonexistent, so this doesn't fix
a user-visible bug.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
arch/x86/kvm/svm.c
arch/x86/kvm/vmx.c

index 82e144a4e514249c140f5c28a8bd0df00869b5ca..1ca12298ffc74f2d783effb35da0953163bbb314 100644 (file)
@@ -3395,6 +3395,7 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
        vcpu->arch.regs[VCPU_REGS_RIP] = svm->vmcb->save.rip;
 
        load_host_msrs(vcpu);
+       kvm_load_ldt(ldt_selector);
        loadsegment(fs, fs_selector);
 #ifdef CONFIG_X86_64
        load_gs_index(gs_selector);
@@ -3402,7 +3403,6 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
 #else
        loadsegment(gs, gs_selector);
 #endif
-       kvm_load_ldt(ldt_selector);
 
        reload_tss(vcpu);
 
index 8da0e45ff7c9cde22d424583adbb2786cf78a72a..6fe7df75bfd4a16cffacf9ef3387c9d63def6adc 100644 (file)
@@ -839,8 +839,6 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx)
 
        ++vmx->vcpu.stat.host_state_reload;
        vmx->host_state.loaded = 0;
-       if (vmx->host_state.fs_reload_needed)
-               loadsegment(fs, vmx->host_state.fs_sel);
        if (vmx->host_state.gs_ldt_reload_needed) {
                kvm_load_ldt(vmx->host_state.ldt_sel);
 #ifdef CONFIG_X86_64
@@ -850,6 +848,8 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx)
                loadsegment(gs, vmx->host_state.gs_sel);
 #endif
        }
+       if (vmx->host_state.fs_reload_needed)
+               loadsegment(fs, vmx->host_state.fs_sel);
        reload_tss();
 #ifdef CONFIG_X86_64
        if (is_long_mode(&vmx->vcpu)) {