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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BN9PR11MB5276.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 12506385-5f39-4e09-bddf-08d9ca9e087d X-MS-Exchange-CrossTenant-originalarrivaltime: 29 Dec 2021 07:37:14.4861 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: HbxOW6FZBquMfYRZJoeBsGD3jFH88HHF0gR1qX5wgbI8y4D0cLvSxJGgaZ7FzEeQklyR/mH0myUxmnnRRVUidQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR11MB1683 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org > From: Sean Christopherson > Sent: Wednesday, December 29, 2021 9:05 AM > > + if (vcpu->arch.xfd_out_of_sync) >=20 > Rather than adding a flag that tracks whether or not the MSR can be writt= en > by > the guest, can't this be: >=20 > if (!vmx_test_msr_bitmap_write(vcpu->loaded_vmcs->msr_bitmap)) > fpu_sync_guest_vmexit_xfd_state(); >=20 and forgot to mention a change different from above. It's in x86 common exit path but above is vmx specific check. I'm not sure whether it's worthy of introducing another kvm_x86_ops callback just for this minor usage. Introducing an extra flag (e.g. vcpu->arch.xfd_disable_interception) sounds simpler here. Thanks Kevin