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KVM: Correct ordering of ldt reload wrt fs/gs reload
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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>
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Avi Kivity authored and Marcelo Tosatti committed Nov 17, 2010
1 parent 59365d1 commit 0a77fe4
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Showing 2 changed files with 3 additions and 3 deletions.
2 changes: 1 addition & 1 deletion arch/x86/kvm/svm.c
Original file line number Diff line number Diff line change
Expand Up @@ -3395,14 +3395,14 @@ 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);
wrmsrl(MSR_KERNEL_GS_BASE, current->thread.gs);
#else
loadsegment(gs, gs_selector);
#endif
kvm_load_ldt(ldt_selector);

reload_tss(vcpu);

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4 changes: 2 additions & 2 deletions arch/x86/kvm/vmx.c
Original file line number Diff line number Diff line change
Expand Up @@ -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
Expand All @@ -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)) {
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