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X-CSE-ConnectionGUID: lx9dvSkIRhGMmy3fUgFxyg== X-CSE-MsgGUID: TmDpbc6rS86E2ZxOCFpgKA== X-IronPort-AV: E=McAfee;i="6600,9927,11078"; a="29879488" X-IronPort-AV: E=Sophos;i="6.08,175,1712646000"; d="scan'208";a="29879488" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2024 10:15:26 -0700 X-CSE-ConnectionGUID: 07pV3FeKSVOSKmj5sk+moQ== X-CSE-MsgGUID: mCnaoW0wQ5+32hL/ibOJcw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,175,1712646000"; d="scan'208";a="33200874" Received: from ldmartin-desk2.corp.intel.com (HELO [10.125.109.60]) ([10.125.109.60]) by orviesa007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2024 10:15:24 -0700 Message-ID: Date: Mon, 20 May 2024 10:15:24 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 24/27] KVM: x86: Enable CET virtualization for VMX and advertise to userspace To: Sean Christopherson , Weijiang Yang Cc: Thomas Gleixner , rick.p.edgecombe@intel.com, pbonzini@redhat.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, peterz@infradead.org, chao.gao@intel.com, mlevitsk@redhat.com, john.allen@amd.com References: <20240219074733.122080-1-weijiang.yang@intel.com> <20240219074733.122080-25-weijiang.yang@intel.com> <39b95ac6-f163-4461-93f3-eaa653ab1355@intel.com> <87r0e0ke8w.ffs@tglx> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/20/24 10:09, Sean Christopherson wrote: >> IIUC, this series tries to tie IBT to SHSTK feature, i.e., IBT cannot be >> exposed as an independent feature to guest without exposing SHSTK at the same >> time. If it is, then below patch is not needed anymore: >> https://lore.kernel.org/all/20240219074733.122080-3-weijiang.yang@intel.com/ > That's a question for the x86 maintainers. Specifically, do they want to allow > enabling XFEATURE_CET_USER even if userspace shadow stack support is disabled. I like the sound of "below patch is not needed anymore". Unless removing the patch causes permanent issues or results in something that's not functional, I say: jettison it with glee. If it's that important, it can be considered on its own merits separately.