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X-CSE-ConnectionGUID: yD+SjvV8TGWQgzEgvNdhdw== X-CSE-MsgGUID: DIaeS1yGS4yU93VGjPRKSw== X-IronPort-AV: E=McAfee;i="6800,10657,11895"; a="88703375" X-IronPort-AV: E=Sophos;i="6.25,260,1779174000"; d="scan'208";a="88703375" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Sep 2026 08:47:50 -0700 X-CSE-ConnectionGUID: WKFC3obMQmC8gOC3zO69xg== X-CSE-MsgGUID: K+2s97SiTjmhdFdbIaXO9Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,260,1779174000"; d="scan'208";a="265434270" Received: from jmaxwel1-mobl.amr.corp.intel.com (HELO [10.125.110.172]) ([10.125.110.172]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Sep 2026 08:47:49 -0700 Message-ID: <225572f8-5636-41fd-9315-ef5efb78f0a5@intel.com> Date: Thu, 3 Sep 2026 08:47:48 -0700 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 10/11] Documentation/x86: Add documentation for TDX's Dynamic PAMT To: Rick Edgecombe , bp@alien8.de, hpa@zytor.com, kas@kernel.org, kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, nik.borisov@suse.com, pbonzini@redhat.com, seanjc@google.com, tglx@kernel.org, vannapurve@google.com, x86@kernel.org, chao.gao@intel.com, yan.y.zhao@intel.com, kai.huang@intel.com, tony.lindgren@linux.intel.com, binbin.wu@intel.com, sohil.mehta@intel.com Cc: Hongyu Ning , Binbin Wu References: <20260903015113.93343-1-rick.p.edgecombe@intel.com> <20260903015113.93343-11-rick.p.edgecombe@intel.com> Content-Language: en-US From: Dave Hansen Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/2/26 18:51, Rick Edgecombe wrote: > +Dynamic PAMT is only enabled when supported and the ``tdx_dpamt=`` kernel > +parameter is set to "on". The feature is off by default because TDX module > +internal details prevent Dynamic PAMT from working on all keyid partitioning > +configurations. When the TDX module is fixed to include these constraints in > +its enumeration of Dynamic PAMT support, kernel support can be changed to > +default on. For more information, consult the Intel TDX documentation about > +Dynamic PAMT. What's the end user visible effect of hitting one of these troublesome "keyid partitioning configurations"?