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Date: Fri, 24 Nov 2023 10:45:02 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Yang Weijiang <weijiang.yang@intel.com>
Cc: seanjc@google.com, pbonzini@redhat.com, dave.hansen@intel.com,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	chao.gao@intel.com, rick.p.edgecombe@intel.com, mlevitsk@redhat.com,
	john.allen@amd.com
Subject: Re: [PATCH v7 03/26] x86/fpu/xstate: Add CET supervisor mode state
 support
Message-ID: <20231124094502.GL3818@noisy.programming.kicks-ass.net>
References: <20231124055330.138870-1-weijiang.yang@intel.com>
 <20231124055330.138870-4-weijiang.yang@intel.com>
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In-Reply-To: <20231124055330.138870-4-weijiang.yang@intel.com>

On Fri, Nov 24, 2023 at 12:53:07AM -0500, Yang Weijiang wrote:

> Note, in KVM case, guest CET supervisor state i.e., IA32_PL{0,1,2}_MSRs,
> are preserved after VM-Exit until host/guest fpstates are swapped, but
> since host supervisor shadow stack is disabled, the preserved MSRs won't
> hurt host.

Just to be clear, with FRED all this changes, right? Then we get more
VMCS fields for SSS state.