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kvm: vmx: Skip all SYSCALL MSRs in setup_msrs() when !EFER.SCE
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Like IA32_STAR, IA32_LSTAR and IA32_FMASK only need to contain guest
values on VM-entry when the guest is in long mode and EFER.SCE is set.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Jim Mattson authored and Paolo Bonzini committed Dec 14, 2018
1 parent db31c8f commit 84c8c5b
Showing 1 changed file with 8 additions and 8 deletions.
16 changes: 8 additions & 8 deletions arch/x86/kvm/vmx/vmx.c
Original file line number Diff line number Diff line change
@@ -1375,19 +1375,19 @@ static void setup_msrs(struct vcpu_vmx *vmx)

save_nmsrs = 0;
#ifdef CONFIG_X86_64
if (is_long_mode(&vmx->vcpu)) {
index = __find_msr_index(vmx, MSR_SYSCALL_MASK);
/*
* The SYSCALL MSRs are only needed on long mode guests, and only
* when EFER.SCE is set.
*/
if (is_long_mode(&vmx->vcpu) && (vmx->vcpu.arch.efer & EFER_SCE)) {
index = __find_msr_index(vmx, MSR_STAR);
if (index >= 0)
move_msr_up(vmx, index, save_nmsrs++);
index = __find_msr_index(vmx, MSR_LSTAR);
if (index >= 0)
move_msr_up(vmx, index, save_nmsrs++);
/*
* MSR_STAR is only needed on long mode guests, and only
* if efer.sce is enabled.
*/
index = __find_msr_index(vmx, MSR_STAR);
if ((index >= 0) && (vmx->vcpu.arch.efer & EFER_SCE))
index = __find_msr_index(vmx, MSR_SYSCALL_MASK);
if (index >= 0)
move_msr_up(vmx, index, save_nmsrs++);
}
#endif

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