Re: [Xen-devel] [PATCH] SVM: correct CPUID event processing

From: Alexandru Stefan ISAILA <aisaila@bitdefender.com>
To: Jan Beulich <jbeulich@suse.com>,
	"xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>
Cc: "Petre Ovidiu PIRCALABU" <ppircalabu@bitdefender.com>,
	"Juergen Gross" <jgross@suse.com>,
	"Kevin Tian" <kevin.tian@intel.com>,
	"Tamas K Lengyel" <tamas@tklengyel.com>,
	"Jun Nakajima" <jun.nakajima@intel.com>, "Wei Liu" <wl@xen.org>,
	"Andrew Cooper" <andrew.cooper3@citrix.com>,
	"Razvan COJOCARU" <rcojocaru@bitdefender.com>,
	"Suravee Suthikulpanit" <suravee.suthikulpanit@amd.com>,
	"Boris Ostrovsky" <boris.ostrovsky@oracle.com>,
	"Roger Pau Monné" <roger.pau@citrix.com>
Subject: Re: [Xen-devel] [PATCH] SVM: correct CPUID event processing
Date: Fri, 20 Sep 2019 08:39:42 +0000	[thread overview]
Message-ID: <57f40bec-d2ad-192f-aeb1-008a0a701fcc@bitdefender.com> (raw)
In-Reply-To: <845737d3-e16e-61d7-7733-0f8b9eddfb45@suse.com>

On 19.09.2019 13:37, Jan Beulich wrote:
> hvm_monitor_cpuid() expects the input registers, not two of the outputs.
> 
> However, once having made the necessary adjustment, the SVM and VMX
> functions are so similar that they should be folded (thus avoiding
> further similar asymmetries to get introduced). Use the best of both
> worlds by e.g. using "curr" consistently. This then being the only
> caller of hvm_check_cpuid_faulting(), fold in that function as well.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Alexandru Isaila <aisaila@bitdefender.com>

> 
> --- a/xen/arch/x86/hvm/hvm.c
> +++ b/xen/arch/x86/hvm/hvm.c
> @@ -3349,14 +3349,28 @@ unsigned long copy_from_user_hvm(void *t
>       return rc ? len : 0; /* fake a copy_from_user() return code */
>   }
>

Useful fold. Maybe a small comment with the reason to have one function 
would help. Something like both SVM and VMX do the same thing, but it's 
up to you if it is necessary.

> -bool hvm_check_cpuid_faulting(struct vcpu *v)
> +int hvm_vmexit_cpuid(struct cpu_user_regs *regs, unsigned int inst_len)

Alex
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel