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AJvYcCVU9o3+AlLz2faGJWo+ElAVqW4lgnC6d1wYAK+tq+SF+moRx+h9HWIOiOMCF1QeBNPntIukd04BWbJLcdM=@vger.kernel.org X-Gm-Message-State: AOJu0YzKznimp3pbiqcLJQFi86nDlOU5yHyik5aPKDOeBqRv5nZiWR0e ywGc6vuoYUNd3ZjAIq9fGDoKYAQEAWHvmJa67EkC7WqNz2egt/TSE7D94ieJIV6FBR/odQqBdlh 8LZ7V5t1GdsOq1Um2Xneh4g== X-Google-Smtp-Source: AGHT+IEsvRhaA+pgvEn2VcIt6EZL6lLvB8OQlgHyuSOj5NMOQERsIQvH6ATMkLPJIOGQBvW8tdGSJDJWdEvdsdMB X-Received: from pjbsm7.prod.google.com ([2002:a17:90b:2e47:b0:312:f650:c7aa]) (user=jthoughton job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:2d47:b0:312:db8f:9a09 with SMTP id 98e67ed59e1d1-313f1c380f7mr29459716a91.14.1750220677882; Tue, 17 Jun 2025 21:24:37 -0700 (PDT) Date: Wed, 18 Jun 2025 04:24:16 +0000 In-Reply-To: <20250618042424.330664-1-jthoughton@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250618042424.330664-1-jthoughton@google.com> X-Mailer: git-send-email 2.50.0.rc2.696.g1fc2a0284f-goog Message-ID: <20250618042424.330664-8-jthoughton@google.com> Subject: [PATCH v3 07/15] KVM: Enable and advertise support for KVM userfault exits From: James Houghton To: Paolo Bonzini , Sean Christopherson , Oliver Upton Cc: Jonathan Corbet , Marc Zyngier , Yan Zhao , James Houghton , Nikita Kalyazin , Anish Moorthy , Peter Gonda , Peter Xu , David Matlack , wei.w.wang@intel.com, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Now that all architectures (arm64 and x86) that utilize "generic" page faults also support userfault exits, advertise support for KVM_CAP_USERFAULT and let userspace set KVM_MEM_USERFAULT in memslots. Signed-off-by: James Houghton Signed-off-by: Sean Christopherson --- include/uapi/linux/kvm.h | 1 + virt/kvm/kvm_main.c | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index e3b871506ec85..0ba265f99f033 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -937,6 +937,7 @@ struct kvm_enable_cap { #define KVM_CAP_ARM_EL2 240 #define KVM_CAP_ARM_EL2_E2H0 241 #define KVM_CAP_RISCV_MP_STATE_RESET 242 +#define KVM_CAP_USERFAULT 243 =20 struct kvm_irq_routing_irqchip { __u32 irqchip; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index bef6760cd1c0e..2962be09d5ebf 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1604,6 +1604,9 @@ static int check_memory_region_flags(struct kvm *kvm, !(mem->flags & KVM_MEM_GUEST_MEMFD)) valid_flags |=3D KVM_MEM_READONLY; =20 + if (IS_ENABLED(CONFIG_KVM_GENERIC_PAGE_FAULT)) + valid_flags |=3D KVM_MEM_USERFAULT; + if (mem->flags & ~valid_flags) return -EINVAL; =20 @@ -4881,6 +4884,9 @@ static int kvm_vm_ioctl_check_extension_generic(struc= t kvm *kvm, long arg) case KVM_CAP_CHECK_EXTENSION_VM: case KVM_CAP_ENABLE_CAP_VM: case KVM_CAP_HALT_POLL: +#ifdef CONFIG_KVM_GENERIC_PAGE_FAULT + case KVM_CAP_USERFAULT: +#endif return 1; #ifdef CONFIG_KVM_MMIO case KVM_CAP_COALESCED_MMIO: --=20 2.50.0.rc2.692.g299adb8693-goog