linux-kernel - Re: [PATCH 25/33] KVM: x86: expose cpuid_entry2

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] [day] [month] [year] [list]

Message-ID: <9079202f-2b0d-4bcf-8f61-36c7234245d1@intel.com>
Date: Thu, 27 Feb 2025 11:03:12 +1300
From: "Huang, Kai" <kai.huang@...el.com>
To: Paolo Bonzini <pbonzini@...hat.com>, <linux-kernel@...r.kernel.org>,
	<kvm@...r.kernel.org>
CC: <seanjc@...gle.com>, Yan Zhao <yan.y.zhao@...el.com>, Rick Edgecombe
	<rick.p.edgecombe@...el.com>
Subject: Re: [PATCH 25/33] KVM: x86: expose cpuid_entry2_find for TDX



On 27/02/2025 7:14 am, Paolo Bonzini wrote:
> Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>

Reviewed-by: Kai Huang <kai.huang@...el.com>

... assuming there will be a changelog, e.g., perhaps something like below:

TDX will need to search a CPUID leaf from a list of per-TD scope CPUID 
entries w/o any vCPU context.  Abstract the code which does CPUID entry 
search from a given list of CPUID entries as kvm_find_cpuid_entry2() and 
Export it for TDX to use.

And one nit below ...

> @@ -141,23 +141,26 @@ static struct kvm_cpuid_entry2 *cpuid_entry2_find(struct kvm_vcpu *vcpu,
>   
>   	return NULL;
>   }
> +EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry2);
>   
>   struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
>   						    u32 function, u32 index)
>   {
> -	return cpuid_entry2_find(vcpu, function, index);
> +	return kvm_find_cpuid_entry2(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
> +				     function, index);
>   }
>   EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry_index);
>   
>   struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
>   					      u32 function)
>   {
> -	return cpuid_entry2_find(vcpu, function, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
> +	return kvm_find_cpuid_entry2(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
> +				     function, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
>   }
>   EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);

... I think we can change both kvm_find_cpuid_entry_index() and 
kvm_find_cpuid_entry() to 'static inline' and place them in the 
kvm/cpuid.h to avoid exporting them.

See attached diff.  Build test only.

View attachment "tdx_cpuid.diff" of type "text/plain" (2682 bytes)