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AJvYcCUjpel8aK0S4PG9jx3q2i0J9cvCkUhQ/WdZ9pyWS/0fESpVCEjBQsFNinjhQRQ0fbRS560/zziKYZu9COY=@vger.kernel.org X-Gm-Message-State: AOJu0Yw13oQrLCqX6bMNCtsuZDG7ULTftov9xz5Ruwq3CQxTbuRMPjY0 vgVkkVcBAh0wYEjuTrwXyLJRNIL6r2W9Kr+gMXzyemMd3Ue5vWlqwrC6li0PeKIVi3B70tybs+S Pu6WDKg== X-Received: from pjzs1.prod.google.com ([2002:a17:90b:701:b0:356:3104:ed7]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:250f:b0:358:ee5f:9c04 with SMTP id 98e67ed59e1d1-358ee5f9f15mr3687808a91.30.1772047376873; Wed, 25 Feb 2026 11:22:56 -0800 (PST) Date: Wed, 25 Feb 2026 11:22:55 -0800 In-Reply-To: <8bed2406e9f5f30f8f01c1da731fae6e040da827.camel@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260225012049.920665-1-seanjc@google.com> <20260225012049.920665-15-seanjc@google.com> <8bed2406e9f5f30f8f01c1da731fae6e040da827.camel@intel.com> Message-ID: Subject: Re: [PATCH 14/14] KVM: x86: Add helpers to prepare kvm_run for userspace MMIO exit From: Sean Christopherson To: Rick P Edgecombe Cc: "pbonzini@redhat.com" , "kas@kernel.org" , "x86@kernel.org" , "zhangjiaji1@huawei.com" , "binbin.wu@linux.intel.com" , Xiaoyao Li , "linux-kernel@vger.kernel.org" , "thomas.lendacky@amd.com" , "kvm@vger.kernel.org" , "linux-coco@lists.linux.dev" , "michael.roth@amd.com" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wed, Feb 25, 2026, Rick P Edgecombe wrote: > On Tue, 2026-02-24 at 17:20 -0800, Sean Christopherson wrote: > > +static inline void __kvm_prepare_emulated_mmio_exit(struct kvm_vcpu *v= cpu, > > + =C2=A0=C2=A0=C2=A0 gpa_t gpa, unsigned int len, > > + =C2=A0=C2=A0=C2=A0 const void *data, > > + =C2=A0=C2=A0=C2=A0 bool is_write) > > +{ > > + struct kvm_run *run =3D vcpu->run; > > + > > + run->mmio.len =3D min(8u, len); >=20 > I would think to extract this to a local var so it can be used twice. Ya, either way works for me. The copy+paste is a little gross, but it's al= so unlikely that anyone is going to modify this code (or if they did, that any= goofs wouldn't be immediately disastrous). > > + run->mmio.is_write =3D is_write; > > + run->exit_reason =3D KVM_EXIT_MMIO; > > + run->mmio.phys_addr =3D gpa; > > + if (is_write) > > + memcpy(run->mmio.data, data, min(8u, len)); > > +} > > + >=20