Re: [RFC PATCH 1/7] x86: Fix the 64-byte boundary enumeration for extended state

From: Yang Zhong <yang.zhong@intel.com>
To: "Tian, Kevin" <kevin.tian@intel.com>
Cc: yang.zhong@intel.com, "Christopherson, ,
	Sean" <seanjc@google.com>,
	"jing2.liu@linux.intel.com" <jing2.liu@linux.intel.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
	"Wang, Wei W" <wei.w.wang@intel.com>,
	"Zeng, Guang" <guang.zeng@intel.com>,
	"pbonzini@redhat.com" <pbonzini@redhat.com>
Subject: Re: [RFC PATCH 1/7] x86: Fix the 64-byte boundary enumeration for extended state
Date: Tue, 11 Jan 2022 10:22:18 +0800	[thread overview]
Message-ID: <20220111022218.GA10706@yangzhon-Virtual> (raw)
In-Reply-To: <BN9PR11MB5276BFF130081C9ED21F89238C509@BN9PR11MB5276.namprd11.prod.outlook.com>

On Mon, Jan 10, 2022 at 04:20:41PM +0800, Tian, Kevin wrote:
> > From: Zhong, Yang <yang.zhong@intel.com>
> > Sent: Friday, January 7, 2022 5:31 PM
> >
> > From: Jing Liu <jing2.liu@intel.com>
> >
> > The extended state subleaves (EAX=0Dh, ECX=n, n>1).ECX[1]
> > are all zero, while spec actually introduces that bit 01
> > should indicate if the extended state component locates
> > on the next 64-byte boundary following the preceding state
> > component when the compacted format of an XSAVE area is
> > used.
> 
> Above would read clearer if you revise to:
> 
> "The extended state subleaves (EAX=0Dh, ECX=n, n>1).ECX[1]
> indicate whether the extended state component locates
> on the next 64-byte boundary following the preceding state
> component when the compacted format of an XSAVE area is
> used.
> 
> But ECX[1] is always cleared in current implementation."

  Thanks Kevin, I will update this in next version.

  Yang