[PATCH v3 3/4] kvm: vmx: Don't set hardware IA32_CSTAR MSR on VM-entry

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



SYSCALL raises #UD in compatibility mode on Intel CPUs, so it's
pointless to load the guest's IA32_CSTAR value into the hardware MSR.

IA32_CSTAR still provides 48 bits of storage on Intel CPUs that have
CPUID.80000001:EDX.LM[bit 29] set, so we cannot remove it from the
vmx_msr_index[] array.

Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
Reviewed-by: Peter Shier <pshier@xxxxxxxxxx>
---
 arch/x86/kvm/vmx.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ee460a21d369..df468980a8c1 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3413,9 +3413,6 @@ static void setup_msrs(struct vcpu_vmx *vmx)
 		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++);
-		index = __find_msr_index(vmx, MSR_CSTAR);
 		if (index >= 0)
 			move_msr_up(vmx, index, save_nmsrs++);
 		/*
-- 
2.19.1.930.g4563a0d9d0-goog




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux