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Message-ID: <f51647de-f427-45fc-a754-0029096fd5d7@intel.com>
Date:   Wed, 29 Nov 2023 22:18:53 +0800
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Subject: Re: [PATCH v7 07/26] x86/fpu/xstate: Warn if kernel dynamic xfeatures
 detected in normal fpstate
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To:     "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
CC:     "Hansen, Dave" <dave.hansen@intel.com>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
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        "pbonzini@redhat.com" <pbonzini@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "john.allen@amd.com" <john.allen@amd.com>,
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        "Gao, Chao" <chao.gao@intel.com>,
        "mlevitsk@redhat.com" <mlevitsk@redhat.com>
References: <20231124055330.138870-1-weijiang.yang@intel.com>
 <20231124055330.138870-8-weijiang.yang@intel.com>
 <8dafb9cb4cb7054ae2a0c1bd19062937148d668b.camel@intel.com>
From:   "Yang, Weijiang" <weijiang.yang@intel.com>
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On 11/28/2023 11:25 PM, Edgecombe, Rick P wrote:
> On Fri, 2023-11-24 at 00:53 -0500, Yang Weijiang wrote:
>> Kernel dynamic xfeatures now are __ONLY__ enabled for guest fpstate,
>> i.e.,
>> none for normal kernel fpstate. The bits are added when guest FPU
>    ^never?

Sure, will change it, thank you!

>> config
>> is initialized. Guest fpstate is allocated with fpstate->is_guest set
>> to
>> %true.
>>
>> For normal fpstate, the bits should have been removed when
>> initializes
>> kernel FPU config settings, WARN_ONCE() if kernel detects normal
>> fpstate
>> xfeatures contains kernel dynamic xfeatures before executes xsaves.
>>
>> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
> Otherwise...
>
> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>