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AJvYcCXW/IWX6RkaDvGi6YAbO6XkGhy4yOegyF2li65FMoekX5P/5fdoN39rgiqV7J6VYpG0Qdc=@vger.kernel.org X-Gm-Message-State: AOJu0YyDYuB7GWGC+WZ/RI/7nG1hPB0PMz6t2d5T9PKcAS7ZhAqJY2xP mh5Zm2MvlwIBw0gE/QLw/XZj9rw7OH+OhCwM95SrrVrZ+u52K8GixSs5tYRBC2/xZHU5+d9tzyM A+z1KyQ== X-Google-Smtp-Source: AGHT+IH6m3f76l6yku6MzokNsOCaSmhZodZjwP6CfTO6JSklzF6cEWk3kWQxsyjylQvGnXRVGHq+qWLVkNs= X-Received: from plbku7.prod.google.com ([2002:a17:903:2887:b0:29f:13e0:4d8d]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:ce08:b0:295:54cb:16ac with SMTP id d9443c01a7336-2a3ee44252dmr36132945ad.18.1767817639553; Wed, 07 Jan 2026 12:27:19 -0800 (PST) Date: Wed, 7 Jan 2026 12:27:18 -0800 In-Reply-To: <741984276082955190f9bf9cedc244cb3cab1556.camel@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260106101646.24809-1-yan.y.zhao@intel.com> <741984276082955190f9bf9cedc244cb3cab1556.camel@intel.com> Message-ID: Subject: Re: [PATCH v3 00/24] KVM: TDX huge page support for private memory From: Sean Christopherson To: Rick P Edgecombe Cc: "ackerleytng@google.com" , "kvm@vger.kernel.org" , Fan Du , Xiaoyao Li , Kai Huang , Dave Hansen , Yan Y Zhao , "thomas.lendacky@amd.com" , "vbabka@suse.cz" , "tabba@google.com" , "david@kernel.org" , "linux-kernel@vger.kernel.org" , "kas@kernel.org" , Ira Weiny , "pbonzini@redhat.com" , "binbin.wu@linux.intel.com" , Isaku Yamahata , "michael.roth@amd.com" , "nik.borisov@suse.com" , Chao P Peng , "francescolavra.fl@gmail.com" , Vishal Annapurve , "sagis@google.com" , Chao Gao , Jun Miao , "jgross@suse.com" , "pgonda@google.com" , "x86@kernel.org" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wed, Jan 07, 2026, Rick P Edgecombe wrote: > On Tue, 2026-01-06 at 15:43 -0800, Sean Christopherson wrote: > > Mapping a hugepage for memory that KVM _knows_ is contiguous and homoge= nous is > > conceptually totally fine, i.e. I'm not totally opposed to adding suppo= rt for > > mapping multiple guest_memfd folios with a single hugepage.=C2=A0=C2=A0= As to whether we > > do (a) nothing, (b) change the refcounting, or (c) add support for mapp= ing > > multiple folios in one page, probably comes down to which option provid= es "good > > enough" performance without incurring too much complexity. >=20 > Can we add "whether we can push it off to the future" to the consideratio= ns > list? The in-flight gmem stuff is pretty complex and this doesn't seem to= have > an ABI intersection. Ya, for sure. The only wrinkle I can think of is if the refcounting someho= w bleeds into userspace, but that seems like it'd be a flaw on its own.