[PATCH] KVM: vmx: fix VPID is 0000H in non-root operation

From	Wanpeng Li <wanpeng.li@hotmail.com>
Newsgroups	linux.kernel
Subject	[PATCH] KVM: vmx: fix VPID is 0000H in non-root operation
Date	2015-09-16 13:40 +0200
Message-ID	<q9je9-3cq-1@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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Reference SDM 28.1:

The current VPID is 0000H in the following situations:
— Outside VMX operation. (This includes operation in system-management 
  mode under the default treatment of SMIs and SMM with VMX operation; 
  see Section 34.14.)
— In VMX root operation.
— In VMX non-root operation when the “enable VPID” VM-execution control 
  is 0.

The VPID should never be 0000H in non-root operation when "enable VPID" 
VM-execution control is 1. However, commit (34a1cd60: 'kvm: x86: vmx: 
move some vmx setting from vmx_init() to hardware_setup()') remove the 
codes which reserve 0000H for VMX root operation. 

This patch fix it by reintroducing reserve 0000H for VMX root operation.

Reported-by: Wincy Van <fanwenyi0529@gmail.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
---
 arch/x86/kvm/vmx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 9ff6a3f..a63b9ca 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6056,6 +6056,8 @@ static __init int hardware_setup(void)
 	memcpy(vmx_msr_bitmap_longmode_x2apic,
 			vmx_msr_bitmap_longmode, PAGE_SIZE);
 
+	set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
+
 	if (enable_apicv) {
 		for (msr = 0x800; msr <= 0x8ff; msr++)
 			vmx_disable_intercept_msr_read_x2apic(msr);
-- 
1.9.1

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[PATCH] KVM: vmx: fix VPID is 0000H in non-root operation Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-16 13:40 +0200
  Re: [PATCH] KVM: vmx: fix VPID is 0000H in non-root operation Jan Kiszka <jan.kiszka@siemens.com> - 2015-09-16 14:40 +0200
    Re: [PATCH] KVM: vmx: fix VPID is 0000H in non-root operation Paolo Bonzini <pbonzini@redhat.com> - 2015-09-16 14:50 +0200
      Re: [PATCH] KVM: vmx: fix VPID is 0000H in non-root operation Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-16 16:00 +0200

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