linux-kernel - Re: [PATCH 05/10] KVM: nVMX: Use vpid_sync_vcpu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87wo8grr83.fsf@vitty.brq.redhat.com>
Date:   Fri, 21 Feb 2020 14:43:08 +0100
From:   Vitaly Kuznetsov <vkuznets@...hat.com>
To:     Sean Christopherson <sean.j.christopherson@...el.com>
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 05/10] KVM: nVMX: Use vpid_sync_vcpu_addr() to emulate INVVPID with address

Sean Christopherson <sean.j.christopherson@...el.com> writes:

> Use vpid_sync_vcpu_addr() to emulate the "individual address" variant of
> INVVPID now that said function handles the fallback case of the (host)
> CPU not supporting "individual address".
>
> Note, the "vpid == 0" checks in the vpid_sync_*() helpers aren't
> actually redundant with the "!operand.vpid" check in handle_invvpid(),
> as the vpid passed to vpid_sync_vcpu_addr() is a KVM (host) controlled
> value, i.e. vpid02 can be zero even if operand.vpid is non-zero.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
> ---
>  arch/x86/kvm/vmx/nested.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
> index 19ac4083667f..5a174be314e5 100644
> --- a/arch/x86/kvm/vmx/nested.c
> +++ b/arch/x86/kvm/vmx/nested.c
> @@ -5150,11 +5150,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
>  		    is_noncanonical_address(operand.gla, vcpu))
>  			return nested_vmx_failValid(vcpu,
>  				VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
> -		if (cpu_has_vmx_invvpid_individual_addr()) {
> -			__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR,
> -				vpid02, operand.gla);
> -		} else
> -			vpid_sync_context(vpid02);
> +		vpid_sync_vcpu_addr(vpid02, operand.gla);
>  		break;
>  	case VMX_VPID_EXTENT_SINGLE_CONTEXT:
>  	case VMX_VPID_EXTENT_SINGLE_NON_GLOBAL:

Reviewed-by: Vitaly Kuznetsov <vkuznets@...hat.com>

-- 
Vitaly