Re: [PATCH v4 2/5] KVM: X86: Expose PKS to guest

From: Paolo Bonzini <pbonzini@redhat.com>
To: Chenyi Qiang <chenyi.qiang@intel.com>,
	Sean Christopherson <seanjc@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
	Xiaoyao Li <xiaoyao.li@intel.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	"x86@kernel.org" <x86@kernel.org>,
	Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@alien8.de>
Subject: Re: [PATCH v4 2/5] KVM: X86: Expose PKS to guest
Date: Fri, 5 Feb 2021 10:25:48 +0100	[thread overview]
Message-ID: <8768ad06-e051-250d-93ec-fa4d684bc7b0@redhat.com> (raw)
In-Reply-To: <20210205083706.14146-3-chenyi.qiang@intel.com>

On 05/02/21 09:37, Chenyi Qiang wrote:
> 
> diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c
> index 57718716cc70..8027f854c600 100644
> --- a/arch/x86/mm/pkeys.c
> +++ b/arch/x86/mm/pkeys.c
> @@ -390,3 +390,9 @@ void pks_key_free(int pkey)
>  	__clear_bit(pkey, &pks_key_allocation_map);
>  }
>  EXPORT_SYMBOL_GPL(pks_key_free);
> +
> +u32 get_current_pkrs(void)
> +{
> +	return this_cpu_read(pkrs_cache);
> +}
> +EXPORT_SYMBOL_GPL(get_current_pkrs);
> diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h
> index bed0e293f13b..480429020f4c 100644
> --- a/include/linux/pkeys.h
> +++ b/include/linux/pkeys.h
> @@ -72,6 +72,10 @@ static inline void pks_mk_readwrite(int pkey)
>  {
>  	pr_err("%s is not valid without PKS support\n", __func__);
>  }
> +static inline u32 get_current_pkrs(void)
> +{
> +	return 0;
> +}
>  #endif /* ! CONFIG_ARCH_HAS_SUPERVISOR_PKEYS */
>  

This would need an ack from the x86 people.  Andy, Boris?

Paolo