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charset=utf-8 Content-Disposition: inline In-Reply-To: <9614d727-97bf-4a50-be13-6754952bec96@intel.com> Received-SPF: pass client-ip=170.10.129.124; envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Fri, Oct 24, 2025 at 10:30:19AM +0800, Xiaoyao Li wrote: > On 10/24/2025 2:59 AM, Peter Xu wrote: > > Guest-memfd is not 100% attached to private, it's a VM-specific memory > > provider. Allow it to be created even without private attributes, for > > example, when the VM can use the guest-memfd memory completely shared. > > > > Signed-off-by: Peter Xu > > --- > > accel/kvm/kvm-all.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > > index f9254ae654..1425dfd8b3 100644 > > --- a/accel/kvm/kvm-all.c > > +++ b/accel/kvm/kvm-all.c > > @@ -2779,10 +2779,8 @@ static int kvm_init(AccelState *as, MachineState *ms) > > } > > kvm_supported_memory_attributes = kvm_vm_check_extension(s, KVM_CAP_MEMORY_ATTRIBUTES); > > - kvm_guest_memfd_supported = > > - kvm_vm_check_extension(s, KVM_CAP_GUEST_MEMFD) && > > - kvm_vm_check_extension(s, KVM_CAP_USER_MEMORY2) && > > - (kvm_supported_memory_attributes & KVM_MEMORY_ATTRIBUTE_PRIVATE); > > + kvm_guest_memfd_supported = kvm_vm_check_extension(s, KVM_CAP_GUEST_MEMFD) && > > + kvm_vm_check_extension(s, KVM_CAP_USER_MEMORY2); > > kvm_pre_fault_memory_supported = kvm_vm_check_extension(s, KVM_CAP_PRE_FAULT_MEMORY); > > if (s->kernel_irqchip_split == ON_OFF_AUTO_AUTO) { > > > The check on KVM_MEMORY_ATTRIBUTE_PRIVATE is dropped silently. But using > guest memfd to serve as private memory does requires the support of > KVM_MEMORY_ATTRIBUTE_PRIVATE. > > My version of the patch was Your version looks good, I'll fetch yours to replace mine. Thanks. -- Peter Xu