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X-CSE-ConnectionGUID: UpuhkVzRQ+6Uo+rSgSOQBA== X-CSE-MsgGUID: nOSvH/QSSSuSqMY4xSkY2g== X-IronPort-AV: E=McAfee;i="6700,10204,11269"; a="32931819" X-IronPort-AV: E=Sophos;i="6.12,191,1728975600"; d="scan'208";a="32931819" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Nov 2024 22:26:41 -0800 X-CSE-ConnectionGUID: 4xBOJ8xgSo2NIknwWKwx0w== X-CSE-MsgGUID: sHZ70yT6QpmUMBHt17+2EQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,191,1728975600"; d="scan'208";a="91756519" Received: from ahunter6-mobl1.ger.corp.intel.com (HELO [10.0.2.15]) ([10.245.89.141]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Nov 2024 22:26:36 -0800 Message-ID: <3576c721-3ef2-40bd-8764-b50912df93a2@intel.com> Date: Thu, 28 Nov 2024 08:26:29 +0200 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 2/7] KVM: TDX: Implement TDX vcpu enter/exit path To: Yan Zhao Cc: Binbin Wu , Xiaoyao Li , pbonzini@redhat.com, seanjc@google.com, kvm@vger.kernel.org, dave.hansen@linux.intel.com, rick.p.edgecombe@intel.com, kai.huang@intel.com, reinette.chatre@intel.com, tony.lindgren@linux.intel.com, dmatlack@google.com, isaku.yamahata@intel.com, nik.borisov@suse.com, linux-kernel@vger.kernel.org, x86@kernel.org, chao.gao@intel.com, weijiang.yang@intel.com References: <20241121201448.36170-1-adrian.hunter@intel.com> <20241121201448.36170-3-adrian.hunter@intel.com> <2f22aeeb-7109-4d3f-bcb7-58ef7f8e0d4c@intel.com> <91eccab3-2740-4bb7-ac3f-35dea506a0de@linux.intel.com> <837bbbc7-e7f3-4362-a745-310fe369f43d@intel.com> Content-Language: en-US From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 28/11/24 07:56, Yan Zhao wrote: > On Fri, Nov 22, 2024 at 04:33:27PM +0200, Adrian Hunter wrote: >> On 22/11/24 07:56, Binbin Wu wrote: >>> >>> >>> >>> On 11/22/2024 1:23 PM, Xiaoyao Li wrote: >>> [...] >>>>> + >>>>> +fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit) >>>>> +{ >>>>> +    struct vcpu_tdx *tdx = to_tdx(vcpu); >>>>> + >>>>> +    /* TDX exit handle takes care of this error case. */ >>>>> +    if (unlikely(tdx->state != VCPU_TD_STATE_INITIALIZED)) { >>>>> +        /* Set to avoid collision with EXIT_REASON_EXCEPTION_NMI. */ >>>> >>>> It seems the check fits better in tdx_vcpu_pre_run(). >>> >>> Indeed, it's cleaner to move the check to vcpu_pre_run. >>> Then no need to set the value to vp_enter_ret, and the comments are not >>> needed. >> >> And we can take out the same check in tdx_handle_exit() >> because it won't get there if ->vcpu_pre_run() fails. > > And also check for TD_STATE_RUNNABLE in tdx_vcpu_pre_run()? Yes, let's also do that. > >>> >>>> >>>> And without the patch of how TDX handles Exit (i.e., how deal with vp_enter_ret), it's hard to review this comment. >>>> >>>>> +        tdx->vp_enter_ret = TDX_SW_ERROR; >>>>> +        return EXIT_FASTPATH_NONE; >>>>> +    } >>>>> + >>>>> +    trace_kvm_entry(vcpu, force_immediate_exit); >>>>> + >>>>> +    tdx_vcpu_enter_exit(vcpu); >>>>> + >>>>> +    vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET; >>>>> +    trace_kvm_exit(vcpu, KVM_ISA_VMX); >>>>> + >>>>> +    return EXIT_FASTPATH_NONE; >>>>> +} >>>>> + >>> [...] >>