| Message ID | BLU436-SMTP979E5F0855A14EAB12C4A5805B0@phx.gbl (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2015-09-16 13:31, Wanpeng Li wrote: > 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); > Good point. BTW, what will happen if allocate_vpid runs out of free slots and returns 0? Will we always fail then...? Jan
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);
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(+)