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 82e144a..1ca1229 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 8da0e45..6fe7df7 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)) {